bmj open€¦ · 3 tun firzara abdul malik1*, chirk jenn ng1 4 1department of primary care...

For peer review only

Knowledge and practice of prostate cancer screening among general practitioners in Malaysia : A cross-sectional study

Journal: BMJ Open

Manuscript ID bmjopen-2016-011467

Article Type: Research

Date Submitted by the Author: 15-Feb-2016

Complete List of Authors: Abdul Malik, Tun Firzara; University of Malaya, Primary Care Medicine Ng, Chirk Jenn; University of Malaya, Department of Primary Care Medicine

<b>Primary Subject Heading</b>:

General practice / Family practice

Secondary Subject Heading: Urology, General practice / Family practice

Keywords: Prostate disease < UROLOGY, screening, PRIMARY CARE, knowledge, practice

For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml

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Knowledge and practice of prostate cancer screening among general 1

practitioners: A cross-sectional study 2

Tun Firzara Abdul Malik1*, Chirk Jenn Ng1 3

1Department of Primary Care Medicine, Faculty of Medicine, University of Malaya, Kuala 4

Lumpur, Malaysia 5

6

*Corresponding author : Tun Firzara Abdul Malik [email protected], +603-7

79492653 8

Chirk Jenn Ng [email protected] 9

10

Keywords: prostate cancer, screening, general practitioners, knowledge, practice 11

Word count: 3789 words 12

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ABSTRACT 20

21

Objective Despite evidence for prostate cancer screening remains controversial, 22

prostate specific antigen (PSA) has been widely used as a screening tool. General 23

practitioners (GPs) play an important role in assisting men to make an informed 24

decision on prostate cancer screening. The aim of this study is to determine the 25

knowledge and practice of prostate cancer screening among GPs. 26

Design Cross-sectional study 27

Setting Private General Practices in Selangor, Malaysia 28

Participants 311 randomly selected full-time private GPs were recruited between 29

September 2013 and January 2014. 30

Outcome measures Questionnaires were distributed to the GPs via postal mail and 31

clinic visits. The main outcomes were: knowledge of prostate cancer risk factors and 32

screening tests; GPs’ prostate cancer screening practices; and factors influencing GPs’ 33

decision to screen for prostate cancer. Associations between covariates and propensity 34

to screen for prostate cancer were determined using logistic regression. 35

Results The response rate was 65%. The proportion of GPs who overestimated the 36

positive predictive values of PSA, digital rectal examination (DRE) and combination of 37

PSA and DRE were 63%, 57% and 64%, respectively. 49.5% of the respondents would 38

routinely screen asymptomatic men for prostate cancer and, of whom 94.9% would use 39

PSA if they intend to screen. Male GPs who would consider having a PSA test done on 40

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themselves were six-times more likely to screen asymptomatic men than GPs who 41

would not have the test (OR = 6.88, 95% CI 1.40-33.73), after adjusting for age and 42

duration of practice. 43

Conclusion GPs overestimated the accuracy of PSA in prostate cancer screening. 44

Their intention to screen for prostate cancer themselves predicted their propensity to 45

screen their patients for prostate cancer. This finding highlights the potential of using a 46

new approach to change GPs’ screening practices via addressing their own screening 47

behaviour. 48

49


Strengths and limitations of this study 51

52

• The participants were selected randomly and it has achieved a reasonable 53

response rate of 65%. Therefore, the findings from this study are likely to be 54

generalizable to the other urban general practices in Malaysia. 55

• There is a possibility that GPs may not report their actual screening practices as 56

we collected self-reported rather than actual practices. 57

58

59

60

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INTRODUCTION 61

Evidence on prostate cancer screening has been contradictory. The results from two 62

major randomized trials in the Europe and the United States of America (USA) were 63

conflicting: the European Randomised Study of Screening for Prostate cancer (ERSPC) 64

(1) showed a reduction in mortality while the Prostate, Lung, Colorectal, Ovarian Cancer 65

(PLCO) trial did not find a reduction in mortality.(2) Recommendations from clinical 66

practice guidelines have also been inconsistent. The European Association of Urology 67

(EAU) and the National Comprehensive Cancer Network (NCCN) recommend 68

screening for prostate cancer,(3, 4) while the US Preventive Service Task Force 69

(USPSTF) (5) is against it. Other organisations which include American Urological 70

Association (AUA),(6) American College of Physicians (ACP) (7) and American Cancer 71

Society (ACS) (8) recommended that doctors should involve men in shared decision 72

making when discussing prostate cancer screening. 73

74

The root of the controversy is whether PSA is beneficial as a screening tool for prostate 75

cancer. PSA screening has a high false positive rate of 80% with relatively low 76

specificity, sensitivity and positive predictive value.(5) The life expectancy may remain 77

the same in most men with prostate cancer as it is a slow growing tumour.(5) Despite 78

this, prostate cancer screening is common, particularly in the primary care setting, 79

where preventive care is encouraged. In Canada, Ireland and New Zealand, more than 80

half of the GPs screen for prostate cancer (9-11) and majority of them overestimated 81

the performance of prostate cancer screening tools.(10, 11) Factors that have been 82

found to influence GPs prostate cancer screening practice are: patients’ age,(10-12) 83

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family history,(12-14) and patients’ request;(12-14) doctors’ age,(10, 15) gender,(10) 84

duration of practice,(10) and influence from guidelines and trials;(12) and whether the 85

practice runs well man clinics, performs occupational health checks and performs other 86

tests routinely with PSA.(10) 87

88

In Malaysia, prostate cancer is the fourth most common cancer among men. Its 89

incidence is rising due to the ageing population and, possibly, an increase in prostate 90

cancer screening rate. However, so far, there is no consensus on prostate cancer 91

screening in the population and there is no clinical practice guideline to guide the GPs 92

whether or not to screen for prostate cancer. It remains unknown whether GPs in 93

Malaysia, in the absence of proper guidance, are screening for prostate cancer and, if 94

so, whether they are aware of the pros and cons of prostate cancer screening. 95

Therefore, the aim of this study was to determine the knowledge and practice of 96

prostate cancer screening among GPs. 97

METHODS 98

We conducted a cross-sectional study in private GP clinics in Petaling District, 99

Selangor, an urban area in Malaysia. The healthcare system in Malaysia is divided into 100

public and private sectors. Patients pay a standard minimal fee for public healthcare 101

system whereas the private sector charges patients based on the services provided. 102

We conducted the study in private GP clinics as PSA test is readily available compared 103

to public primary care clinics. In public primary care clinics, the blood test sample need 104

to be sent to tertiary public hospital and may take a long time to get the result. The 105

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inclusion criteria were fulltime private GPs who managed adult male patients. The 106

sampling frame consisted of 683 private GP clinics in Petaling District registered with 107

the Private Medical Practice Control Unit. In practices with more than one GP, only one 108

GP was chosen by the practice to participate. The sample size was calculated using 109

Stata version 11.0. By using 50% as the hypothesised screening rate with postulated 110

rate of 40% (margin of error=10%), 0.05 as α and 80% as power, the estimated sample 111

size was 194. Considering a response rate of 60%, the final sample size was 311. 112

Simple random sampling was used to select the practices via computer-generated 113

numbers. 114

115

A self-administered questionnaire was adapted from a previous survey developed by 116

Drummond et al from National Cancer Registry Ireland (1). The questionnaire consisted 117

of 34 items with sections on: (i) GPs’ socio demographic profile; (ii) practice profile; (iii) 118

knowledge on prostate cancer risk factors and prostate cancer screening tests; (iv) 119

prostate cancer screening practice; and (v) management of PSA result and information 120

needs. Positive predictive value was defined as the likelihood that a positive result 121

indicates prostate cancer. We performed content and face validation of the 122

questionnaire among eight healthcare professionals who have expertise in prostate 123

cancer screening including urologists, family medicine specialists and GPs. The 124

questionnaire was modified based on the feedback from the expert panel. A pilot study 125

was conducted to look at the feasibility and acceptability of the study. 126

127

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Data collection was carried out from September 2013 to January 2014. Questionnaires, 128

participant information sheet and consent form were posted to 311 randomly-selected 129

general practices. The questionnaire was assigned a numerical code to ensure 130

confidentiality. A reminder letter was sent two weeks later. Due to poor response rate 131

from the postal survey (10%), the researcher visited the remaining GPs personally to 132

improve the response rate. 133

134

Statistical analysis 135

We used the Statistical Package for Social Sciences (SPSS) version 21.0 to manage 136

and analyse the data. There were no missing data because the participants were 137

contacted to complete the missing data in the questionnaires. Percentages were used 138

to summarise categorical data. Mean and standard deviation was used to describe 139

continuous variables which were normally distributed while median for those which were 140

not normally distributed. We used Pearson’s chi-square test to test univariate 141

associations between categorical variables. We used the item ‘Do you usually screen 142

asymptomatic men for prostate cancer’ as the dependent variable. Multivariate logistic 143

regression analysis was performed to identify independent factors which influenced the 144

GPs’ decision to screen for prostate cancer. We analysed the level of knowledge on 145

PPV for prostate cancer screening by grouping the responses into correct or over-146

estimation which are incorrect. The correct estimation of PPV for PSA alone and DRE 147

alone is <30% while PPV for combination of both is <50%. (10, 16-20) 148

149

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150

151

152

RESULTS 153

154

Response rate and socio demographic profile of participants 155

156

We distributed questionnaires by mail to 311 clinics. Only 30 GPs (9.6%) returned the 157

questionnaires by post. Subsequently, we visited the remaining 281 GP clinics. Nine 158

GPs were excluded from the study (five were not fulltime GPs and four did not see adult 159

male patients). A total of 196 GPs agreed to participate in the study (30 by mail, 166 160

from clinic visits), giving a response rate of 65% (196/302). The targeted sample size of 161

194 was achieved. Table 1 shows the GPs’ and practice profile. Reasons for non-162

participation were lack of time and they were not interested in the research. 163

Table 1. General practitioners’ and practice profile 164

Characteristics of respondents N ( %) / mean / median (n=196)

Gender Male

128 (65.3%)

Age Mean age ± SD (years) [range]

48.3 ± 11.4 [26-83]

Length of practice Mean age ± SD (years) [range] Median (years)

15.8 ± 10.7 [0.5 – 53]

15

GPs with postgraduate qualifications

53 (27.0%)

Number of GPs in practice Mean ± SD [range]

3.0 ± 2.8 [1-16]

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Median

2

Number of patients in a day Mean ± SD [range] Median

36.01 ± 18.2 [4-90]

30

165

GPs’ knowledge on prostate cancer risk factors and screening tests 166

Majority of the respondents correctly identified ‘increased age of over 50 years’ 167

(97.4%) and ‘having a first degree relative with prostate cancer’ (82.7%) increase the 168

risk of prostate cancer. Fewer of them (31.1%) were aware that having a first degree 169

relative with breast cancer increases the risk of prostate cancer (Table 2). 170

More than half of the GPs (63.3%) overestimated the likelihood that a positive 171

PSA result indicated prostate cancer (PPV), and 56.6% overestimated the PPV of DRE. 172

There were 64.3% of the GPs who overestimated the PPV of PSA and DRE combined. 173

The results are summarised in Table 3. 174

Table 2. GPs’ knowledge of prostate cancer risk factors 175

Knowledge on risk factors ‘For each of the following, please indicate whether you believe they influence the risk of developing prostate cancer’.

Number who

answered correctly (n=196)

%

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Increased age (over 50 years)

(increases risk) 1st degree relative with prostate cancer (increases risk) 1st degree relative with breast cancer (Increases risk) Benign prostatic hyperplasia (does not affect risk) Current smoking (does not affect risk) High dietary fat intake (does not affect risk)

191

162

61

43

36

35

97.4

82.7

31.1

21.9

18.4

17.9

176

Table 3. GPs’ knowledge on positive predictive value of prostate cancer 177

screening methods 178

Knowledge on PPV Number (n=196)

%

PPV of PSA Correct estimation <30% Overestimate >30% Not sure

PPV of DRE Correct estimation <30% Overestimate >30% Not sure

PPV of PSA and DRE

Correct estimation <50% Overestimate >50% Not sure

54

124 18

50 111 35

47 126 23

27.6 63.3 9.2

25.5 56.6 17.9

24.0 64.3 11.7

179

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GPs’ practice on prostate cancer screening 180

Almost half of the respondents (49.5%) reported that they would usually screen 181

asymptomatic men for prostate cancer. Nearly all GPs (94.9%) would use PSA if they 182

intended to screen for prostate cancer. At least half of the GPs (51.5%) believed healthy 183

men aged 50 years and over should be tested for PSA annually or less while 22.4% 184

believed that PSA test should be performed only when a man with risk factors develops 185

lower urinary tract symptoms. Majority (76%) of the GPs reported that they frequently 186

informed the patient that his PSA was being checked as part of screening package. 187

61.2% of the GPs would frequently discuss the implication of an abnormal proposed 188

PSA test. Only 20.4% of them would frequently discuss the treatments of prostate 189

cancer in general terms before performing a PSA test. Majority of the male GPs 190

(89.8%) would consider undergoing a PSA test themselves. 191

192

Factors associated with the propensity of GPs to screen asymptomatic men for 193

prostate cancer 194

From univariate analyses, we found three factors to be significantly associated with 195

GPs’ propensity to screen for prostate cancer: older age group (p = 0.02), longer 196

duration of practice (p = 0.03) and GPs who considered having PSA test done on 197

themselves (p=0.01). By using the logistic regression model, GPs’ who would have PSA 198

test themselves was the only independent predictor for GPs’ propensity to screen for 199

prostate cancer (Table 4). 200

201

202

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203

204

205

206

207

208

209

Table 4. Logistic regression analysis: Factors associated with the propensity of 210

GPs to screen asymptomatic men for prostate cancer 211

Factors

Propensity to screen N (%)

Unadjusted OR (95%CI)

P value Adjusted OR (95%CI)

P value

GP characteristics

Age group

<40 40-60 >60

16/47 (34.0) 59/115 (51.3) 22/34 (64.7)

1 2.04(1.01-4.13) 3.55(1.41-8.97)

p=0.02

1 1.09(0.33-3.62) 1.82(0.32-10.42)

0.88 0.50

Length of practice (years)

≤10 11-20 21-30 >30

25/70 (35.7) 43/79 (54.4) 19/30 (63.3) 10/17 (58.8)

1 2.15(1.11-4.16) 3.11(1.28-7.56) 2.57(0.87-7.59)

p=0.03

1 2.44(0.82-7.23) 1.81(0.44-7.47) 1.49(0.23-9.54

0.11 0.41 0.68

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212

*among male participants 213

214

215

DISCUSSION 216

217

There are three main findings in this study: i) more than half of the GPs overestimated 218

the PPV of prostate cancer screening tools; ii) almost half of the GPs (49.5%) would 219

screen asymptomatic men for prostate cancer and majority (94.9%) would use PSA if 220

they intended to screen despite unavailability of national guideline and the controversies 221

with regards to prostate cancer screening; and iii) GPs who would consider having a 222

PSA test done on themselves were six times more likely to screen asymptomatic men 223

than GPs who would not have the test. 224

225

Majority of the respondents correctly identified first degree family history of prostate 226

cancer (82.7%) and increased age of more than 50 years (97.4%) as risk factors for 227

prostate cancer. However, more than half of the respondents (68.9%) were unaware of 228

Consider having a PSA test yourself* No Yes

2/13 (15.4) 65/115 (56.5)

1 7.3(1.55-34.43)

p=0.01

1 6.88(1.40-33.73)

0.017

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family history of breast cancer in first degree relative as a risk factor for prostate cancer. 229

These findings are similar to the previous study done in Ireland and USA.(10, 12) This 230

could be due to the perception that prostate cancer is a male disease and hence 231

doctors may not link it to breast cancer. 232

233

Our study also revealed that there was poor knowledge on the performance of prostate 234

cancer screening tools. More than half of the GPs believed that the PPV of PSA (alone), 235

DRE (alone) and combination of PSA and DRE were higher than the values reported in 236

the literatures.(16-20) This finding is also similar to the study done in Ireland where 54% 237

overestimated the likelihood that a positive PSA result indicated prostate cancer and 238

68% overestimated the PPV of PSA and DRE.(10) Another similar study done in New 239

Zealand also reported that majority of GPs overestimated the PPV for the DRE and 240

more than one third overestimated the PPV of the PSA.(9) This could be due to lack of 241

update or awareness among GPs on prostate cancer screening methods. Further study 242

needs to be done to find out the reasons regarding the gaps of knowledge among the 243

GPs. This is important as overestimation imply that GPs might screen excessively and 244

might not have given men accurate information about the screening test. 245

246

There was a variation in GPs’ practice in prostate cancer screening. In this study, about 247

half of the GPs (49.5%) screened asymptomatic men for prostate cancer; this is lower 248

than the study done in Canada and the UK, where 87% and 76% of the GPs would 249

screen asymptomatic men for prostate cancer, respectively.(11, 13) The high screening 250

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rate in Canada was found to be related to the fee-for-service scheme and high-volume 251

practice.(11) The GPs’ screening behaviour in Canada and UK are also influenced by 252

having a local guideline which recommended GPs to offer prostate cancer screening 253

readily followed by discussing the risks and benefits with the patients.(13, 21) In 254

Malaysia, GPs are almost evenly divided between those who screen and do not screen 255

which is probably due to the fact that local guideline is not available and thus screening 256

might be based on individual beliefs or preferences as well as taking into account the 257

cost that patients need to pay for the test. 258

259

However, this study found that most (94.9%) of the respondents would use PSA if they 260

intended to screen for prostate cancer. This finding paralleled that of an Irish study 261

where more than three-quarters of the GPs reported that they would usually use PSA to 262

screen for prostate cancer.(10) However, this study was conducted before the more 263

recent recommendations from USPSTF, AUA, and ACS were developed which 264

recommend against screening actively for prostate cancer. Nevertheless, the GPs in 265

this study still actively performed PSA testing for their patients which may be explained 266

by lack of awareness and familiarity with recent international guidelines.(22) Another 267

reason could be due to their belief that early detection can improve survival for men with 268

prostate cancer as what has been reported by majority of GPs in Canada and 269

Australia.(11, 23) It could also be due to the fear of litigation if they refused to perform 270

PSA test for patients who requested for it who might later be diagnosed with prostate 271

cancer.(23, 24) Media also play a role in encouraging men to actively screen for 272

prostate cancer.(9, 25) 273

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274

In this study, majority of the GPs believed that they should screen healthy men aged 50 275

years and above at least on an annual basis. This is different from previous studies 276

done in Ireland and New Zealand where only about 30% would test men for PSA every 277

year or more frequently.(9, 10) Another study by Curran et al. reported that majority of 278

the GPs would only screen annually for men above 70 years old.(11) The 2013 AUA 279

guideline recommends screening interval of two years or more as compared to annual 280

screening to reduce over diagnosis and false positive results.(6) This again could be 281

due to the GPs’ own beliefs and preferences and absence of local policy to guide them 282

on the screening practice. 283

284

Up to a quarter of GPs from this study would not routinely disclose to their patient that 285

his PSA was being checked, in contrast to only 10% GPs from the Irish study.(10) 286

Similarly, 39% of GPs would not routinely discuss the implications of an abnormal PSA 287

test and treatments of prostate cancer prior to PSA testing. This is of concern as this 288

would mean that men were not involved in making the decision whether or not to 289

undergo prostate cancer screening. This is consistent with a situational analysis 290

conducted in Malaysia which found that patients were not provided with adequate 291

information to make an informed decision.(26) Shared decision making approach has 292

been recommended by a number of prostate cancer screening guidelines published 293

recently.(6-8) The reasons for GPs not disclosing and discussing the pros and cons of 294

prostate cancer screening with men could be due to the lack of knowledge or skills in 295

communicating risks to patients.(27) Currently, there is no structured shared decision 296

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making training in Malaysia. Cultural and language diversity may also hinder the GP in 297

communicating risk effectively.(26) GPs might also be concerned that they might lose 298

patients or patients may become anxious and decide not to take up the test if the risks 299

were informed prior to testing.(27) 300

301

This study found that GPs’ personal inclination of having PSA test done on themselves 302

was a significant independent predictor for them to screen for prostate cancer in their 303

patients. This is similar with the previous study conducted by Drummond et al where 304

male GPs who would have a PSA test themselves were 8-times more likely to perform 305

PSA test for asymptomatic men than GPs who would not have a test.(10) A study 306

carried out by Haggerty el al. also revealed that the ordering of cancer screening tests 307

was highest among physicians who believed that routine screening was recommended 308

compared to those who think recommendation was unclear or not recommended.(28) 309

GPs’ beliefs are usually reinforced by their own and patients’ experiences as well as by 310

their interactions with their colleagues, opinion leaders, and pharmaceutical 311

representatives.(29) In Australia, although the guideline recommends against screening 312

for prostate cancer, many GPs still would not change their current practice unless the 313

evidence shows that screening for prostate cancer is harmful.(23) 314

315

In this study, other socio demographic characteristics of GP, practice characteristics 316

and knowledge of PPV of prostate cancer screening methods did not significantly 317

influence the GPs to screen for prostate cancer. A study done in the USA also did not 318

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find any association between demographic, practice characteristic or knowledge scores 319

and GPs’ prostate cancer screening behaviour.(30) Knowledge has not been found to 320

be associated with a higher propensity to screen in another study by Tasian et al.(24) 321

Moran et al. reported that physician’s knowledge may not be an important factor that 322

influence physician’s decision to screen for prostate cancer due to the lack of definitive 323

evidence to support the use of PSA.(31) Therefore, this highlights that patient care may 324

be prejudiced by the doctor’s own personal view and experience rather than knowledge 325

or evidence. 326

327

The strength of this study is that the participants were selected randomly and it has 328

achieved a reasonable response rate of 65%. Therefore, the findings from this study are 329

likely to be generalizable to the other urban general practices in Malaysia. However, as 330

we collected self-reported rather than actual practices, there is a possibility that GPs 331

may not report their actual screening practices. 332

333

The findings from this study highlight a need to convince and educate GPs’ on the pros 334

and cons of prostate cancer screening as well as the importance of involving men in 335

shared decision making before ordering PSA tests. A national guideline on prostate 336

cancer screening would be useful to highlight the current controversies and provide 337

guidance for GPs on the practice of prostate cancer screening. Patient decision support 338

tools, such as a patient decision aid, can be used to inform men on the clinical 339

equipoise and guide them to make an informed decision about prostate cancer 340

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screening (45). Qualitative studies should be conducted to explore, understand and 341

explain the factors that influence Malaysian GPs to screen for prostate cancer, 342

particularly what influence their decision to perform PSA on themselves. 343

CONCLUSION 344

This study found that there more than half of the GPs would screen and perform PSA 345

test despite lack of consensus on prostate cancer screening. They did not routinely 346

involve men in making an informed decision about prostate cancer screening. In 347

addition, we found that GPs’ willingness to perform PSA test on themselves significantly 348

influenced their decision to perform PSA testing for their patients. This important finding 349

highlights the need for future studies to explore how GPs’ personal health beliefs and 350

practice influence their clinical decision making. 351

352

Acknowledgements 353

The authors thank Associate Professor Dr Claire Choo Wan Yuen who provided 354

expertise in analysis of the data. The authors acknowledge all respondents for their 355

participation in the study. 356

357

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Footnotes 358

Authors’ contributions All authors contributed to the design and conduct of the study. 359

TFAM collected the data. TFAM and CJN participated in analysis, data interpretation 360

and preparing the manuscript. All authors read and approved the final manuscript. 361

Funding This work was supported by University of Malaya postgraduate research fund 362

(grant number: P0037/2013A). 363

Competing interests The authors have no competing interests. 364

365

Ethics approval This study was approved by the University Malaya Medical Centre 366

Medical Ethics Committee (reference number: 968.6). Written informed consent was 367

obtained from participants. 368

Authors’ information 369

TFAM Lecturer in Department of Primary Care Medicine. CJN Professor in Department 370

of Primary Care Medicine 371

Data sharing statement 372

No additional data are available 373

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rectal examination in subsequent screening visits in the European randomized study of 426

screening for prostate cancer (ERSPC), Rotterdam. Eur Urol. 2008;54(3):581-8. Epub 427

2008/04/22. 428

20. Kuppusamy S QK, Razack AH, Dublin N. Assessment of Diagnostic performance 429

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21. Nathan A. Hoag, Davidson RA, Pommerville PJ. Prostate cancer screening 432

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22. Francke A, Smit M, de Veer A, et al. Factors influencing the implementation of 435

clinical guidelines for health care professionals: A systematic meta-review. BMC Med 436

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23. Ilic D, Murphy K, Green S. What do general practitioners think and do about 438

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2013/12/11. 440

24. Tasian GE, Cooperberg MR, Cowan JE, et al. Prostate specific antigen 441

screening for prostate cancer: knowledge of, attitudes towards, and utilization among 442

primary care physicians. Urol Oncol. 2012;30(2):155-60. Epub 2010/08/31. 443

25. Star T. Check your prostate: Prostate cancer screening is vital in the early 444

detection of prostate diseases. The Star. 2007. 445

26. Ng CJ, Lee PY, Lee YK, et al. An overview of patient involvement in healthcare 446

decision-making: a situational analysis of the Malaysian context. BMC Health Serv Res. 447

2013;13:408. Epub 2013/10/15. 448

27. Davis K, Haisfield L, Dorfman C, et al. Physicians' attitudes about shared 449

decision making for prostate cancer screening. Fam Med. 2011;43(4):260-6. Epub 450

2011/04/19. 451

28. Haggerty J, Tudiver F, Brown JB, et al. Patients' anxiety and expectations: how 452

they influence family physicians' decisions to order cancer screening tests. Can Fam 453

Physician. 2005;51:1658-9. Epub 2006/08/24. 454

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29. Gabbay J, le May A. Evidence based guidelines or collectively constructed 455

"mindlines?" Ethnographic study of knowledge management in primary care. BMJ 456

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30. Johnson K, Chang M, Sun Y, et al. Attitudes and knowledge of primary care 458

physicians regarding prostate cancer screening. J Cancer Educ. 2013;28(4):679-83. 459

Epub 2013/08/22. 460

31. Moran WP, Cohen SJ, Preisser JS, et al. Factors influencing use of the prostate-461

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STROBE 2007 (v4) Statement—Checklist of items that should be included in reports of cross-sectional studies

Section/Topic Item

# Recommendation

Reported on

page #

Title and abstract 1 (a) Indicate the study’s design with a commonly used term in the title or the abstract 1

(b) Provide in the abstract an informative and balanced summary of what was done and what was found 2-3

Introduction

Background/rationale 2 Explain the scientific background and rationale for the investigation being reported 4

Objectives 3 State specific objectives, including any prespecified hypotheses 5

Methods

Study design 4 Present key elements of study design early in the paper 5

Setting 5 Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data

collection

5

Participants

6

(a) Give the eligibility criteria, and the sources and methods of selection of participants 5,6

Variables 7 Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if

applicable

6

Data sources/

measurement

8* For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe

comparability of assessment methods if there is more than one group

6

Bias 9 Describe any efforts to address potential sources of bias 6, 7

Study size 10 Explain how the study size was arrived at 6

Quantitative variables 11 Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and

why

7

Statistical methods 12 (a) Describe all statistical methods, including those used to control for confounding 7

(b) Describe any methods used to examine subgroups and interactions 7

(c) Explain how missing data were addressed 7

(d) If applicable, describe analytical methods taking account of sampling strategy

(e) Describe any sensitivity analyses

Results

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Participants 13* (a) Report numbers of individuals at each stage of study—eg numbers potentially eligible, examined for eligibility,

confirmed eligible, included in the study, completing follow-up, and analysed

8

(b) Give reasons for non-participation at each stage 8

(c) Consider use of a flow diagram

Descriptive data 14* (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential

confounders

8

(b) Indicate number of participants with missing data for each variable of interest

Outcome data 15* Report numbers of outcome events or summary measures 8-11

Main results 16 (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, 95% confidence

interval). Make clear which confounders were adjusted for and why they were included

12

(b) Report category boundaries when continuous variables were categorized 12

(c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period

Other analyses 17 Report other analyses done—eg analyses of subgroups and interactions, and sensitivity analyses

Discussion

Key results 18 Summarise key results with reference to study objectives 13

Limitations 19 Discuss limitations of the study, taking into account sources of potential bias or imprecision. Discuss both direction and

magnitude of any potential bias

17

Interpretation 20 Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from

similar studies, and other relevant evidence

13-17

Generalisability 21 Discuss the generalisability (external validity) of the study results 17

Other information

Funding 22 Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on

which the present article is based

19

*Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies.

Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE

checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at http://www.plosmedicine.org/, Annals of Internal Medicine at

http://www.annals.org/, and Epidemiology at http://www.epidem.com/). Information on the STROBE Initiative is available at www.strobe-statement.org.

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Journal: BMJ Open

Manuscript ID bmjopen-2016-011467.R1


Date Submitted by the Author: 20-May-2016





Keywords: Prostate disease < UROLOGY, screening, PRIMARY CARE, knowledge, practice


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practitioners in Malaysia: A cross-sectional study 2



Lumpur, Malaysia 5

6


79492653 8


10



13

14

15

16

17

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19

ABSTRACT 20

21

Objective Screening for prostate cancer screening remains controversial. General 22


decision on prostate cancer screening. The aim of this study was to determine the 24

knowledge and practice of prostate cancer screening among private GPs in Malaysia. 25













routinely screen asymptomatic men for prostate cancer; of whom, 94.9% would use 38

PSA to screen. Male GPs who would consider having a PSA test done on themselves 39

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3

were six-times more likely to screen asymptomatic men than GPs who would not have 40

the test (OR = 6.88, 95% CI 1.40-33.73), after adjusting for age and duration of practice. 41




new approach to change GPs’ screening practices via addressing GPs’ own screening 45

behaviour. 46

47



50

• The participants were selected randomly. 51

• Although the response rate was less than 70%, this is considered reasonable for 52

surveys targeting physicians which is generally lower. 53

• The findings from this study may not be generalizable to GPs in the public sector 54

and rural setting. 55


the information was self-reported. 57

58

59

60

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4

INTRODUCTION 61


major randomized trials in Europe and the United States of America (USA) were 63


(1, 2) showed a reduction in mortality while the Prostate, Lung, Colorectal, Ovarian 65

Cancer (PLCO) trial did not find a reduction in mortality.(3, 4) Recommendations from 66

clinical practice guidelines have also been inconsistent. The European Association of 67

Urology (EAU) and the National Comprehensive Cancer Network (NCCN) recommend 68




Society (ACS) (10) recommend that doctors should involve men in shared decision 72


74

The root of the controversy is whether PSA testing as a screening tool for prostate 75

cancer confers net benefit. Relatively low prostate cancer sensitivity of 20.5% was 76

reported for PSA cut-off values of 4.0ng/ml; however, the sensitivity of PSA for 77

aggressive prostate cancer (Gleason grade 8 or higher) was greater at 51%. (11) PSA 78

testing has a high false positive rate of 80% with low positive predictive value.(7) 79

Prostate biopsy, as a result of positive screening result, may cause anxiety, physical 80

discomfort, bleeding and infection (12) while prostate cancer treatment may result in 81

sexual dysfunction, urinary incontinence and bowel problems. (13) Overdiagnosis is 82

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also another potential harm as life expectancy may remain unchanged in most men with 83

prostate cancer as it is a slow growing tumour.(7) 84

85

Despite this, prostate cancer screening is common, particularly in the primary care 86

setting, where preventive care is encouraged. In Canada, Ireland and New Zealand, 87

more than half of the GPs screen their male patients for prostate cancer (14-16) and 88

majority of them overestimated the performance of prostate cancer screening tools.(15, 89

16) Factors that have been found to influence GPs prostate cancer screening practice 90

are: patients’ age,(15-17) family history,(17-19) and patients’ request;(17-19) doctors’ 91

age,(15, 20) gender,(15) duration of practice,(15) and influence from guidelines and 92

trials;(17) and whether the practice runs well man clinics, performs occupational health 93

checks and performs other tests routinely with PSA.(15) 94

95

Several risk factors have been associated with prostate cancer which are increased age 96

and family history of prostate cancer. (21) Family history of first degree relative with 97

breast cancer was also found to increase a man’s risk of prostate cancer, (22) 98

especially carriers of BRCA2 mutations. (23) There were also several studies which 99

have looked into other factors such as smoking, dietary intake and benign prostate 100

hyperplasia but the results were not significant. (24-27) 101

102

In Malaysia, prostate cancer is the fourth most common cancer among men. (28) Its 103

incidence is rising due to ageing population and, possibly, an increase in prostate 104

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screening in the population and there is no clinical practice guideline to guide GPs 106

whether or not to screen for prostate cancer. There is also no data on PSA testing rate 107

in Malaysia. Hence, it remains unknown whether GPs in Malaysia, in the absence of 108

proper guidance, are screening for prostate cancer and, if so, whether they are aware of 109

the pros and cons of prostate cancer screening. Therefore, the aim of this study was to 110

determine the knowledge and practice of prostate cancer screening among private GPs 111

in Malaysia. 112

METHODS 113

We conducted a cross-sectional study in private GP clinics in Petaling District, which is 114

an urban area located in the state of Selangor, Malaysia, adjacent to the capital of 115

Kuala Lumpur. The healthcare system in Malaysia is divided into public and private 116

sectors. Patients pay a standard minimal fee for public healthcare system whereas the 117

private sector charges patients based on the services provided. We conducted the 118

study in private GP clinics as PSA test is readily available while in the public primary 119

care clinics, the test is not available and it is not part of the policy to screen for prostate 120

cancer. 121

122

The inclusion criteria were fulltime private GPs who managed adult male patients. The 123

sampling frame consisted of all private GP clinics in Petaling District which has a total of 124

683 clinics. All GP clinics are registered with the Private Medical Practice Control Unit. 125

In practices with more than one GP, only one GP was chosen by the practice to 126

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7

participate. The sample size was calculated using Stata version 11.0. By using 50% as 127

the predicted screening rate with margin of error of 10%, α of 0.05 and power of 80%, 128

the estimated sample size was 194. Considering a response rate of 60%, the final 129

sample size was 311. Simple random sampling was used to select the practices via 130

computer-generated numbers. 131

132


Drummond et al from National Cancer Registry Ireland (15). The questionnaire 134

consisted of 34 items with sections on: (i) GPs’ sociodemographic profile; (ii) practice 135

profile; (iii) knowledge on prostate cancer risk factors and screening tests; (iv) prostate 136

cancer screening practice; and (v) management of PSA results and information needs. 137

Positive predictive value was defined as the likelihood that a positive result indicates 138

prostate cancer. We performed content and face validation of the questionnaire among 139

eight healthcare professionals who have expertise in prostate cancer screening 140

including urologists, family medicine specialists and GPs. The questionnaire was 141

modified based on the feedback from the expert panel. A pilot study was conducted to 142

look at the feasibility and acceptability of the study. Ten GPs participated in the pilot 143

study. 144

145




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from the postal survey (9.6%), the researcher visited the remaining GPs personally to 150

improve the response rate. The researcher followed the code of ethics when 151

approaching the GPs at their clinics. The participants were allowed to answer the 152

questions privately and the researcher avoided influencing them in any way. 153

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154





to summarise categorical data. Mean and standard deviation were used to describe 159


skewed. We used Pearson’s chi-square test to test for univariate associations between 161

categorical variables. We used the item ‘Do you usually screen asymptomatic men for 162

prostate cancer’ as the dependent variable. Multivariate logistic regression analysis was 163

performed to identify independent factors which influenced GPs’ decision to screen for 164

prostate cancer. Only factors that were found to be statistically significant (p<0.05) in 165

univariate analyses were included in the multivariable model. When we analysed the 166

level of knowledge of PPV for prostate cancer screening, overestimation was 167

considered incorrect. We considered the correct estimation of PPV for PSA alone and 168

DRE alone as <30% while PPV for combination of both as <50%. (15, 29, 30) Several 169

continuous variables were grouped into categories: (i) age of GP (<40, 40-60 and >60) 170

and (ii) length of practice (≤10, 11-20, 21-30, >30). These categories are based on 171

stages of the GP career. We hypothesise that at different stages of GPs’ career, their 172

practice of prostate screening might change. 173

174

175

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RESULTS 176

177


179










Gender Male

128 (65.3%)


48.3 ± 11.4 [26-83]


15.8 ± 10.7 [0.5 – 53]

15


53 (27.0%)

Number of GPs in practice Mean ± SD [range] Median

3.0 ± 2.8 [1-16]

2


36.01 ± 18.2 [4-90]

30

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Majority of the respondents correctly answered the questions on ‘increased age 189

of over 50 years’ (97.4%) and ‘having a first degree relative with prostate cancer’ 190

(82.7%) increase the risk of prostate cancer. Fewer of them (31.1%) were aware that 191

having a first degree relative with breast cancer increases the risk of prostate cancer 192

(Table 2). The proportion of GPs who overestimated the PPV of PSA, DRE and both 193

combined were 63.3%, 56.6% and 64.3%, respectively. The results are summarised in 194

Table 3. 195



Number who


%



191

162

61

43

36

35

97.4

82.7

31.1

21.9

18.4

17.9

197

198

199

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Table 3. GPs’ knowledge of positive predictive value of prostate cancer screening 200

methods 201


%



PPV of PSA and DRE


54

124 18

50 111 35

47 126 23

27.6 63.3 9.2

25.5 56.6 17.9

24.0 64.3 11.7

202

GPs’ practice of prostate cancer screening 203


asymptomatic men for prostate cancer. There is no significant difference in screening 205

rates between those who responded by mail and those who responded after visiting 206

their clinics (56.7% vs 48.2%, p=0.39). Nearly all GPs (94.9%) would use PSA if they 207


men aged 50 years and above should be tested for PSA annually or less while 22.4% 209






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217


prostate cancer 219

220


GPs’ propensity to screen for prostate cancer (i) older age group (p = 0.02) with 222

unadjusted OR 2.04 (95%CI 1.01-4.13) for age group 40 to 60 and 3.55 (95%CI 1.41-223

8.97) for age group above 60; (ii) longer duration of practice (p = 0.03) with unadjusted 224

OR of 2.15 (95%CI 1.11-4.16) for 11 to 20 years of practice and 3.11 (95%CI 1.28-7.56) 225

for 21 to 30 years of practice; and (iii) GPs who considered having PSA test done on 226

themselves (p=0.01) with unadjusted OR of 7.30 (95%CI 1.55-34.43) (Table 4). 227

228

By using the logistic regression model, GPs’ who would have PSA test themselves was 229

the only independent predictor of GPs’ propensity to screen for prostate cancer with OR 230

6.88 (95%CI 1.40-33.73) (Table 4). 231

232

233

234

235

236

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239


Factors




P value

GP characteristics Age group <40 40-60 >60

Gender Male Female

16/47 (34.0) 59/115 (51.3) 22/34 (64.7) 64/128 (50.0) 33/68 (48.5)

1 2.04(1.01-4.13) 3.55(1.41-8.97)

1.06(0.59-1.91) 1

p=0.02

p=0.85

1 1.09(0.33-3.62) 1.82(0.32-10.42)

0.88 0.50


≤10 11-20 21-30 >30

25/70 (35.7) 43/79 (54.4) 19/30 (63.3) 10/17 (58.8)

1 2.15(1.11-4.16) 3.11(1.28-7.56) 2.57(0.87-7.59)

p=0.03

1 2.44(0.82-7.23) 1.81(0.44-7.47) 1.49(0.23-9.54

0.11 0.41 0.68

Knowledge PPV of PSA <30% (correct) Overestimate Not sure PPV of DRE <30% (correct) Overestimate Not sure PPV of PSA & DRE <50% (correct) Overestimate Not sure

29/54 (53.7) 61/124 (49.2) 7/18 (38.9) 24/50 (48.0) 58/111 (52.2) 15/35 (42.8) 25/47 (53.2) 62/126 (49.2) 10/23 (43.4)

1 0.55 (0.19-1.63) 0.66 (0.24-1.81)

1 0.81 (0.34-1.94) 0.69 (0.32-1.47)

1 0.68 (0.25-1.85) 0.79 (0.32-1.94)

p=0.55

p=0.61

p=0.74


2/13 (15.4) 65/115 (56.5)

1 7.3(1.55-34.43)

p=0.01

1 6.88(1.40-33.73)

0.017

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DISCUSSION 241

242

There are three main findings in this study. Firstly, more than half of the GPs 243

overestimated the PPV of prostate cancer screening tools. Secondly, almost half of the 244

GPs (49.5%) would screen asymptomatic men for prostate cancer and majority (94.9%) 245

would use PSA if they intended to screen despite unavailability of national guideline and 246

the controversies with regards to prostate cancer screening. Finally, GPs who would 247

consider having a PSA test done on themselves were six times more likely to screen 248

asymptomatic men than GPs who would not have the test. 249

250








258





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of the GPs overestimated the likelihood that a positive PSA result indicated prostate 263

cancer and 68% overestimated the PPV of PSA and DRE.(15) Another study done in 264

New Zealand also reported that majority of GPs overestimated the PPV for DRE and 265






271








readily followed by discussing the risks and benefits with the patients.(18, 34) In this 279

study, GPs were almost evenly divided between those who screened and did not screen 280


might be based on individual beliefs and preferences as well as taking into account the 282

cost that patients need to pay for the test. It could also be due to PSA test being part of 283

a screening package available in the GP clinics. 284

285

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screen for prostate cancer.(15) However, this study was conducted before the recent 289

revised recommendation from USPSTF, AUA, and ACS which recommend against 290

screening actively for prostate cancer. Nevertheless, the GPs in this study still actively 291

performed PSA testing for their patients which may be explained by lack of awareness 292

and familiarity with recent international guidelines.(35) Another reason could be due to 293

their belief that early detection can improve survival for men with prostate cancer, which 294

was reported by majority of GPs in Canada and Australia.(16, 36) GPs are also 295

concerned about litigation should the patient later be diagnosed with prostate 296



299


years and above for prostate cancer, at least on an annual basis. This is different from 301

previous studies done in Ireland and New Zealand where only about 30% would test 302

men for PSA every year or more frequently.(14, 15) Another study by Curran et al. 303

reported that majority of the GPs would only screen annually for men above 70 years 304

old.(16) The 2013 AUA guideline recommends screening interval of two years or more 305

as compared to annual screening to reduce over diagnosis and false positive results.(8) 306

This again could be due to the GPs’ own beliefs and preferences and absence of local 307

policy to guide them on the screening practice. 308

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309

Up to a quarter of GPs in this study would not routinely disclose to their patient that his 310

PSA was being checked; in contrast, only 10% of the GPs from Ireland would do so.(15) 311

Similarly, in this study, 39% of GPs would not routinely discuss the implications of an 312

abnormal PSA test and treatments of prostate cancer prior to PSA testing. This is of 313

concern as this would mean that men would not be involved in making decisions 314

whether or not to undergo prostate cancer screening. This is consistent with a 315

situational analysis conducted in Malaysia which found that patients were not provided 316

with adequate information to make an informed decision.(39) Shared decision making 317

approach has been recommended by a number of prostate cancer screening guidelines 318

published recently.(8-10) The reasons for GPs not disclosing and discussing the pros 319

and cons of prostate cancer screening with men could be due to the lack of knowledge 320

or skills in communicating risks to patients.(40) Currently, there is no structured shared 321

decision making training in Malaysia. Cultural and language diversity may also hinder 322

GPs’ communication with their patients about the risks and benefits of prostate 323

cancer.(39) GPs may also worry that they might lose their patients or patients may 324

become anxious and decide not to take up the test if the risks were informed prior to 325

testing.(40) 326

327


was a significant independent predictor for them to screen their patients for prostate 329

cancer. This is similar to the previous study conducted by Drummond et al where male 330

GPs who would have a PSA test themselves were 8-times more likely to perform PSA 331

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test for asymptomatic men than GPs who would not have a test.(15) A study carried out 332

by Haggerty el al. also revealed that the ordering of cancer screening tests was highest 333

among physicians who believed that routine screening was recommended compared to 334

those who think recommendation was unclear or not recommended.(41) GPs’ beliefs 335

are usually reinforced by their own and patients’ experiences as well as by their 336

interactions with their colleagues, opinion leaders, and pharmaceutical 337

representatives.(42) In Australia, although the guideline recommends against prostate 338

cancer screening, many GPs still would not change their current practice unless the 339


341

In this study, sociodemographic characteristics of GP, and knowledge of PPV of 342

prostate cancer screening methods did not significantly influence GPs’ propensity to 343

screen for prostate cancer. A study done in the USA also did not find any associations 344

between demographic, practice characteristic or knowledge scores and GPs’ prostate 345

cancer screening behaviour.(43) Knowledge has not been found to be associated with a 346

higher propensity to screen in another study by Tasian et al.(37) Moran et al. reported 347

that physician’s knowledge may not be an important factor that influence physician’s 348

decision to screen for prostate cancer due to the lack of definitive evidence to support 349

the use of PSA.(44) Therefore, this highlights that patient care may be prejudiced by the 350

doctor’s own personal view and experience rather than knowledge or evidence. 351

352

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achieved a reasonable response rate of 65%. Although the response rate was less than 354

70%, this is considered reasonable for surveys targeting physicians which is generally 355

lower. (45) However, the findings from this study could not be generalizable to the 356

public GPs and rural setting. As we collected self-reported data, there is a possibility 357

that GPs may not report their actual screening practices. Another limitation is the small 358

number of events (propensity to screen) in GPs who did not consider having the PSA 359

test (n=2/13). This may affect the validity of the regression model. 360

361











CONCLUSION 372

This study found that more than half of the GPs would screen and perform PSA test 373

despite lack of consensus on prostate cancer screening. They did not routinely involve 374

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men in making an informed decision about prostate cancer screening. In addition, we 375

found that GPs’ willingness to perform PSA test on themselves significantly influenced 376

their decision to perform PSA testing for their patients. This important finding highlights 377

the need for future studies to explore how GPs’ personal health beliefs and practice 378

influence their clinical decision making. 379

380


The authors thank Associate Professor Dr Claire Choo Wan Yuen for providing 382



385

Footnotes 386







393

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11. Thompson IM, Ankerst DP, Chi C, Goodman PJ, Tangen CM, Lucia MS, et al. Assessing prostate 428

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men in a country with no guidelines: a national survey of general practitioners. BMC Family Practice. 440

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making for prostate cancer screening. Family medicine. 2011;43(4):260-6. 503

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expectations: how they influence family physicians' decisions to order cancer screening tests. Can Fam 505

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Ethnographic study of knowledge management in primary care. BMJ. 2004;329(7473):1013. 508

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physicians regarding prostate cancer screening. Journal of cancer education : the official journal of the 510

American Association for Cancer Education. 2013;28(4):679-83. 511

44. Moran WP, Cohen SJ, Preisser JS, Wofford JL, Shelton BJ, McClatchey MW. Factors influencing 512

use of the prostate-specific antigen screening test in primary care. Am J Manag Care. 2000;6:315 - 24. 513

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Prostate Cancer Screening

Questionnaire

for General Practitioners

Thank you for taking the time to complete this questionnaire

ID

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The aim of this survey is to find out the knowledge and practices of prostate cancer screening

among general practitioners. This will help to identify any gaps which we hope to use it for

future education purposes eg. continuing medical education (CME) or guideline.

The questionnaire will take approximately 15 minutes to complete. Please fill in the

appropriate tick boxes or write your answer in the spaces provided. Your answers will be

kept strictly confidential. Please return the completed questionnaire to the investigator in the

pre-paid envelope provided.

If you have any questions, please do not hesitate to contact the study investigator:

Dr. Tun Firzara Abdul Malik

Department of Primary Care Medicine

University Malaya Medical Centre

Jalan Universiti, 59100 Kuala Lumpur

Tel: 014 6416961 ; email: [email protected]

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mailto:[email protected]



3

G1. How would you classify yourself?

Full time GP 1 Part-time GP/locum 2

G2. What sex are you? Male 1 Female 2

G3. What age are you? ____________________ (age on your last birthday)

G4. How long have you been in general practice (years)? ____________________

G5. Do you have any of the following postgraduate qualifications?

If

Other, please describe:

G6. Did you work or complete any of your training in another country? Yes 1 No 2

If Yes, where was it? U.K 1 U.S.A 2 Australia 3 Other 4

If Other, please state:

G7. Do you have a special area of interest? Yes 1 No 2

If Yes, what is your area of interest? (Please tick as many boxes as apply)

Men’s health 1 Palliative care 2 Research 3 Urological problems 4 Cancer detection/screening 5 Other 6


Masters in Family Medicine 1 MRCP 5 Diploma in Family Medicine 2 Diploma in Geriatric Medicine 6 FRACGP 3 Medical Doctorate (MD) 7 MRCGP 4 Other 8

SECTION A: GP DETAILS

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G8. Have you ever held a postgraduate post in urology? Yes 1 No 2

If Yes: A. At what level was it? House officer 1 Medical officer 2 Other 3


B. How long was the post for? < 1 month 1 1-6 months 2 7-12 months 3 Other 4

If Other, please describe:

G9. Have you attended continuing medical education (CME) session where the main topic was prostate cancer

screening? Yes 1 No 2

If Yes, when was the most recent? Within the last year 1 1- 5 yrs ago 2 >5 yrs ago 3

P1. How many doctors are there in your practice?

How many full time GPs?

How many part-time GPs

Comments:

P2. How many patients do you see in a day on average?

(If you don’t know exactly, please give your best estimate.)

P3. What percentage of your time is spent seeing patients for Occupational Health Assessments?

0% 1 1-25% 2 26-50% 3 51-75% 4 >75% 5

P4: Are you actively involved in General Practice teaching? Yes 1 No 2

If yes, who are the students you teach?

Medical students 1 GP Trainees/Master students 2 Other 3


Urological problems 4 Cancer detection/screening 5 Other 6

SECTION B: PRACTICE DETAILS

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P5. Does your practice run a ‘Men’s Health’ Clinic or something similar? Yes 1 No 2

If Yes:

A. Are these clinics held? Weekly 1 Fortnightly 2 Monthly 3 Bimonthly 4 Other 5


B. How many men attend each clinic? <10 1 11-20 2 21-30 3 >30 4 Other 5


C1. For each of the following, please indicate whether you believe they influence the risk of developing prostate

cancer:

Does not

affect risk

Reduces

risk

Increases

risk

Don’t

know A. Increased age (over 50 years) 1 2 3 4 B. 1

st degree relative with prostate cancer 1 2 3 4

C. Current smoking 1 2 3 4 D. High dietary fat intake 1 2 3 4 E. 1

st degree relative with breast cancer 1 2 3 4

F. Benign Prostatic Hyperplasia 1 2 3 4

C2. For the following tests, what is the likelihood that a positive result indicates prostate cancer (positive

predictive value)? [Prostate specific antigen (PSA); Digital Rectal Exam (DRE)]

<10% 10-30% 30-50% >50% Not sure

A. PSA level 1 2 3 4 4 B. DRE 1 2 3 4 4 C. PSA and DRE 1 2 3 4 4

C3. Do you usually screen asymptomatic men for prostate cancer?

Yes 1 No 2


SECTION C: PROSTATE CANCER TESTING PRACTICE

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C4. If you intend to screen for prostate cancer, do you use PSA as a screening test?

Yes 1 No 2

If Yes, in what age groups? (Please tick as many as apply)

<30 yrs 1 30-39 yrs 2 40-49 yrs 3 50-59 yrs 4 60-64 yrs 5

65-69 yrs 6 70-74 yrs 7 75-79 yrs 8 ≥ 80 yrs 9

C5. These questions relate to when, and on whom, you perform PSA testing. Do you order:

[*Digital Rectal Exam (DRE); **Transrectal Ultrasound (TRUS)]

Frequently Sometimes Rarely Never

A. PSA testing actively? 1 2 3 4 B. PSA test for men who attend with unrelated complaints? 1 2 3 4 C. PSA test for men with lower urinary tract symptoms? 1 2 3 4 D. PSA test for men with a family history of prostate cancer? 1 2 3 4 E. PSA test for men as part of an occupational health assessment?

1 2 3 4

F. PSA test for men as a follow-up to medical procedures eg.

*DRE or **TRUS? 1 2 3 4

G. PSA test on men who request for the test? 1 2 3 4

C6: Do you perform any other blood tests routinely together with a PSA test?

Yes 1 No 2

If Yes, which tests do you perform? Alkaline Phosphatase (ALP) 1 Creatine Kinase 2

Testosterone 3 Other 4


C7. These questions relate to the consultation prior to PSA testing. Do you:


A. inform the patient that his PSA level is being checked, as

part of screening package? 1 2 3 4

B. discuss the implication of the proposed PSA test, if it was to return as abnormal?

1 2 3 4

C. discuss the treatments of prostate cancer in general terms, at

this stage? 1 2 3 4

D. ask, prior to testing, whether the patient has ejaculated in the

preceding week?? 1 2 3 4

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C8. Men who might have prostate cancer may present to their general practitioners in different ways.

For the following presentations of men, please indicate which tests, if any you would be likely to

perform: (Please tick as many boxes as apply)

A. Mr Smith (aged 55 yrs) is fit and well and presents PSA 1

to you for his annual ‘checkup’. He has no significant DRE 2

medical or family history. Refer to a urologist 3

None of the above 4

Other 5

If Other, please state

B. Mr Jones (aged 55 yrs) is well but is concerned that he PSA 1

is at risk of getting cancer. His brother was diagnosed DRE 2

with prostate cancer this week and his aunt died in her Refer to a urologist 3

forties of breast cancer. None of the above 4

Other 5


C. Mr Jacob (aged 55 yrs) has returned to your clinic PSA 1

for a follow-up after having radiotherapy for prostate DRE 2

cancer one year ago. Refer to a urologist 3

None of the above 4

Other 5


D. Mr Green (aged 55 yrs) is well and has reluctantly PSA 1

arrived to see you at your clinic. His wife has DRE 2

persuaded him to attend after she saw a documentary Refer to a urologist 3

on TV about prostate cancer. He has come to ask None of the above 4

your advice about whether he should have a test done. Other 5


C9. How often do you think a PSA test should be performed in healthy men aged 50 years and over? (Please tick

one box).

Annually or less 1

Every two years 2

More than every two years 3

When a man with risk factors develops lower urinary tract symptoms 4

(eg. frequency, urgency, dysuria, nocturia, poor stream, hesitancy, dribbling, incomplete voiding)

No need to perform PSA 5

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C10.A. Do you, or your practice, have a policy on PSA testing? Yes 1 No 2

B. If Yes, is it? a) a personal policy 1 a practice policy 2

b) an informal policy 1 a written policy 2

C. What year was it implemented?

Comments:

C11. Has your own practice with regard to PSA testing changed in the last 5 years? Yes 1 No 2

If Yes, please describe:

M1. How do you respond to an abnormal PSA result eg. 6ng/ml (normal <4ng/ml)?

(Please tick’Yes’ or ‘No’ for all statements A until F)

A. Repeat the test Yes 1 No 2 B. Seek advice from the lab Yes 1 No 2 C. Seek advice from urology Yes 1 No 2 D. Counsel the patient and refer to urology Yes 1 No 2 E. Refer directly to urology clinic Yes 1 No 2 F. Other Yes 1 No 2

If Other, please comment:

M2. For a man aged 55 at average risk of prostate cancer with a negative DRE, what is the lowest PSA level at

which you would recommend a urological assessment to look for prostate cancer? (Please tick one box only)

2.5-3.9 ng/ml 1

4.0-7.0 ng/ml 2

7.1-10.0 ng/ml 3

>10.0 ng/ml 4

Use laboratory reference range 5

SECTION D: MANAGEMENT OF PSA RESULTS

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M3. For a man aged 65 at average risk of prostate cancer with a negative DRE, what is the lowest PSA level at which you would recommend a urological assessment? (Please tick one box only)

2.5-3.9 ng/ml 1

4.0-7.0 ng/ml 2

7.1-10.0 ng/ml 3

>10.0 ng/ml 4


M4. Are you involved in the care of patients with prostate cancer once the diagnosis is made?

Yes 1 No 2

If yes, please describe in what ways are you involved?

_______________________________________________________________________________________________

_______________________________________________________________________________________________

M5. Has your own practice with regard to referral for urological assessment changed over recent years?

Yes 1 No 2

If Yes, please describe: ____________________________________________________________________________

_______________________________________________________________________________________________

M6. Have you had an asymptomatic patient aged under 60 years who had prostate cancer picked up via a PSA

test?

Yes 1 No 2

If Yes, has this influenced your practice in this matter? Yes 1 No 2

If Yes, please comment: ___________________________________________________________________________

_______________________________________________________________________________________________

M7. Would you consider having a PSA test done yourself in the future?

Yes 1 No 2 Not applicable 3


_______________________________________________________________________________________________



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M8. Do you believe there is a need for national guidelines in relation to the use of PSA testing in General

Practice?

Yes 1 No 2

Comment: ______________________________________________________________________________________

_______________________________________________________________________________________________

M9: Do you feel you need more information with regard to: (Please tick as many as apply)

PSA testing 1 Prostate cancer risk factors 2

Prostate cancer detection/diagnosis 3 Prostate cancer treatment 4

Prostate cancer survival 5 Other 6

If Other, please state: _____________________________________________________________________________

_______________________________________________________________________________________________

M10. If there is anything else you wish to add about PSA testing or prostate cancer, please use the box

below.

Thank you very much for taking the time to participate in this survey.

Please return your completed survey in the enclosed prepaid envelope to:




Jalan University, 59100 Kuala Lumpur

If you have any queries about this study, please do not hesitate to contact me at:

Tel: 014 6416961; email: [email protected]



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Section/Topic Item

# Recommendation

Reported on

page #



Introduction

Background/rationale 2 Explain the scientific background and rationale for the investigation being reported 4-5


Methods



collection

6

Participants

6

(a) Give the eligibility criteria, and the sources and methods of selection of participants 6


applicable

9

Data sources/

measurement



9

Bias 9 Describe any efforts to address potential sources of bias 7-8



why

9






Results

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confounders

10





14




Discussion




19



15-18


Other information



21





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Journal: BMJ Open

Manuscript ID bmjopen-2016-011467.R2


Date Submitted by the Author: 11-Aug-2016





Keywords: Prostate disease < UROLOGY, PRIMARY CARE, Urological tumours < ONCOLOGY, PREVENTIVE MEDICINE


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practitioners in Malaysia: A cross-sectional study 2



Lumpur, Malaysia 5

6


79492653 8


10



13

14

15

16

17

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ABSTRACT 20

21

Objective Screening for prostate cancer screening remains controversial. General 22


decision on prostate cancer screening. The aim of this study was to determine the 24

knowledge and practice of prostate cancer screening among private GPs in Malaysia. 25













routinely screen asymptomatic men for prostate cancer; of whom, 94.9% would use 38

PSA to screen. Male GPs who would consider having a PSA test done on themselves 39

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were six-times more likely to screen asymptomatic men than GPs who would not have 40

the test (OR = 6.88, 95% CI 1.40-33.73), after adjusting for age and duration of practice. 41




new approach to change GPs’ screening practices via addressing GPs’ own screening 45

behaviour. 46

47



50

• The participants were selected randomly. 51

• Although the response rate was less than 70%, this is considered reasonable for 52

surveys targeting physicians which is generally lower. 53

• The findings from this study may not be generalizable to GPs in the public sector 54

and rural setting. 55


the information was self-reported. 57

58

59

60

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INTRODUCTION 61


major randomized trials in Europe and the United States of America (USA) were 63


(1, 2) showed a reduction in mortality while the Prostate, Lung, Colorectal, Ovarian 65

Cancer (PLCO) trial did not find a reduction in mortality.(3, 4) Recommendations from 66

clinical practice guidelines have also been inconsistent. The European Association of 67

Urology (EAU) and the National Comprehensive Cancer Network (NCCN) recommend 68




Society (ACS) (10) recommend that doctors should involve men in shared decision 72


74

The root of the controversy is whether PSA testing as a screening tool for prostate 75

cancer confers net benefit. Relatively low prostate cancer sensitivity of 20.5% was 76

reported for PSA cut-off values of 4.0ng/ml; however, the sensitivity of PSA for 77

aggressive prostate cancer (Gleason grade 8 or higher) was greater at 51%. (11) PSA 78

testing has a high false positive rate of 80% with low positive predictive value.(7) 79

Prostate biopsy, as a result of positive screening result, may cause anxiety, physical 80

discomfort, bleeding and infection (12) while prostate cancer treatment may result in 81

sexual dysfunction, urinary incontinence and bowel problems. (13) Overdiagnosis is 82

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also another potential harm as life expectancy may remain unchanged in most men with 83

prostate cancer as it is a slow growing tumour.(7) 84

85

Despite this, prostate cancer screening is common, particularly in the primary care 86

setting, where preventive care is encouraged. In Canada, Ireland and New Zealand, 87

more than half of the GPs screen their male patients for prostate cancer (14-16) and 88

majority of them overestimated the performance of prostate cancer screening tools.(15, 89

16) Factors that have been found to influence GPs prostate cancer screening practice 90

are: patients’ age,(15-17) family history,(17-19) and patients’ request;(17-19) doctors’ 91

age,(15, 20) gender,(15) duration of practice,(15) and influence from guidelines and 92

trials;(17) and whether the practice runs well man clinics, performs occupational health 93

checks and performs other tests routinely with PSA.(15) 94

95

Several risk factors have been associated with prostate cancer which are increased age 96

and family history of prostate cancer. (21) Family history of first degree relative with 97

breast cancer was also found to increase a man’s risk of prostate cancer, (22) 98

especially carriers of BRCA2 mutations. (23) There were also several studies which 99

have looked into other factors such as smoking, dietary intake and benign prostate 100

hyperplasia but the results were not significant. (24-27) 101

102

In Malaysia, prostate cancer is the fourth most common cancer among men. (28) Its 103

incidence is rising due to ageing population and, possibly, an increase in prostate 104

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screening in the population and there is no clinical practice guideline to guide GPs 106

whether or not to screen for prostate cancer. There is also no data on PSA testing rate 107

in Malaysia. Hence, it remains unknown whether GPs in Malaysia, in the absence of 108

proper guidance, are screening for prostate cancer and, if so, whether they are aware of 109

the pros and cons of prostate cancer screening. Therefore, the aim of this study was to 110

determine the knowledge and practice of prostate cancer screening among private GPs 111

in Malaysia. 112

METHODS 113

We conducted a cross-sectional study in private GP clinics in Petaling District, which is 114

an urban area located in the state of Selangor, Malaysia, adjacent to the capital of 115

Kuala Lumpur. The healthcare system in Malaysia is divided into public and private 116

sectors. Patients pay a standard minimal fee for public healthcare system whereas the 117

private sector charges patients based on the services provided. We conducted the 118

study in private GP clinics as PSA test is readily available while in the public primary 119

care clinics, the test is not available and it is not part of the policy to screen for prostate 120

cancer. 121

122

The inclusion criteria were fulltime private GPs who managed adult male patients. The 123

sampling frame consisted of all private GP clinics in Petaling District which has a total of 124

683 clinics. All GP clinics are registered with the Private Medical Practice Control Unit. 125

In practices with more than one GP, only one GP was chosen by the practice to 126

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participate. The sample size was calculated using Stata version 11.0. By using 50% as 127

the predicted screening rate with margin of error of 10%, α of 0.05 and power of 80%, 128

the estimated sample size was 194. Considering a response rate of 60%, the final 129

sample size was 311. Simple random sampling was used to select the practices via 130

computer-generated numbers. 131

132


Drummond et al from National Cancer Registry Ireland (15). The questionnaire 134

consisted of 34 items with sections on: (i) GPs’ sociodemographic profile; (ii) practice 135

profile; (iii) knowledge on prostate cancer risk factors and screening tests; (iv) prostate 136

cancer screening practice; and (v) management of PSA results and information needs 137

(Appendix 1). Positive predictive value was defined as the likelihood that a positive 138

result indicates prostate cancer. We performed content and face validation of the 139

questionnaire among eight healthcare professionals who have expertise in prostate 140

cancer screening including urologists, family medicine specialists and GPs. The 141

questionnaire was modified based on the feedback from the expert panel. A pilot study 142

was conducted to look at the feasibility and acceptability of the study. Ten GPs 143

participated in the pilot study. 144

145




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from the postal survey (9.6%), the researcher visited the remaining GPs personally to 150

improve the response rate. The researcher followed the code of ethics when 151

approaching the GPs at their clinics. The participants were allowed to answer the 152

questions privately and the researcher avoided influencing them in any way. 153

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to summarise categorical data. Mean and standard deviation were used to describe 158


skewed. We used Pearson’s chi-square test to test for univariate associations between 160

categorical variables. We used the item ‘Do you usually screen asymptomatic men for 161

prostate cancer’ as the dependent variable. Multivariate logistic regression analysis was 162

performed to identify independent factors which influenced GPs’ decision to screen for 163

prostate cancer. Only factors that were found to be statistically significant (p<0.05) in 164

univariate analyses were included in the multivariable model. When we analysed the 165

level of knowledge of PPV for prostate cancer screening, overestimation was 166

considered incorrect. We considered the correct estimation of PPV for PSA alone and 167

DRE alone as <30% while PPV for combination of both as <50%. (15, 29, 30) Several 168

continuous variables were grouped into categories: (i) age of GP (<40, 40-60 and >60) 169

and (ii) length of practice (≤10, 11-20, 21-30, >30). These categories are based on 170

stages of the GP career. We hypothesise that at different stages of GPs’ career, their 171

practice of prostate screening might change. Female participants were excluded from 172

the multivariable model for the item ‘Would you consider having a PSA test done 173

yourself in the future?’ because the question was not relevant to them and hence was 174

not asked. 175

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