Communicating Risk

Dr Katherine TeareGP Educator Fellow

RISK

‘The probability that a hazard will give rise to harm’

Risk Communication

Probability of risk occuring

Importance of the adverse event

Effect on the patient

Perception - how it varies

Awareness of risk in question

Understanding of risk including statistics

Dependent upon information presented to patients

May be at odds with public health message - population level

Problems with communicating

riskPatients, AND DOCTORS, struggle to understand numbers and statistics

Basic numeracy also an issue for some

Methods: FramingAttribute framing: ‘Positive’ vs ‘Negative’ e.g. 82% chance survival 5yrs post diagnosis breast cancer or 18% chance dying

Goal framing: describe consequences as gain vs loss e.g. screening will improve chance survival vs not participating will reduce survival

Method: Presenting Risk Reduction

RRR: reduction of risk in intervention group relative to risk control group e.g. early detection breast cancer reduces risk dying from breast cancer by 15%

ARR: difference risk between two groups e.g. early detection with mammography reduces risk dying from breast cancer by 0.05%

NNT: number of patients who need to be treated (or screened) to prevent one additional adverse outcome e.g. 2000 women need to have regular mammograms for more than 10 years to prolong one life

Method: Personalising risk

informationGive population based risk estimate OR on basis individual risk factors

Personalised risk info in screening context leads to more accurate risk perception, improved knowlesge and increased uptake screening

Method: Decision Aids

Clear evidence based information on choices available

Improve patient participation in decision making

Case Study

Bridget Jones - just turned 50, fit and well, no reg meds. Menarche 14yrs, no FHx breast cancer, first child aged 26yrs. Sister told her mammogram will detect a cancer before she can feel a lump but she is concerned about false alarms and unnecessary treatment

Case Study cont...NHS National Prescribing Centre has a breast screening decision aid

Explains if 1000 women aged 50-70 attend regular mammograms for 10 years 970 will not have breast cancer but 130 of these will have had unnecessary investigations

30 will have breast cancer, 4 would have been clinically inconsequential, for 23 the fact that detected during screening does not alter outcome but 3 women will live longer because found at screening

Other cases to discuss

Concerned 63 year old man with 1 x nocturia re PSA testing

Cardiff Health Check: 31 year old woman, alleged sexual assault in teens but never in another sexual relationship re cervical screening

Newly diagnosed 57 year old hypertensive male patient with QRISK score 21% who has heard only bad things about statins

References

Communicating risk. Ahmed H, Naik G, Willoughby H, Edwards A. BMJ 2012;344:e3996