Early results from SIPS: Screening for brief intervention

Professor Simon Coulton

Overview of screening in SIPS

Three study settings

- Criminal Justice, Primary Care, Emergency Departments

Three screening tools

- Modified SASQ, FAST, Paddington Alcohol Test

Two screening approaches

- Universal screen vs Targeting by presentation

One gold standard

- AUDIT score

The screening tools

Modified SASQ

Measures heavy episodic drinking, 6 for women or 8 for men standard drinks on a single occasion.

Monthly or less is a screen positive

M-SASQ PositiveNegative

The screening tools

Fast Alcohol Screening Test

Measures M-SASQ. If negative probes using questions derived from AUDIT

M-SASQ PositiveNegative

AUDIT QuestionsNegative Positive

The screening tools

Paddington Alcohol Test.

Targeted at specific presenting conditions, asks if attendance is alcohol related, if negative asks M-SASQ.

M-SASQ PositiveNegative

Alcohol related

attendanceNegative Positive

MSASQ is embedded in each screening tool…

The criminal Justice SettingUniversal screening only M-SASQ versus FAST

• Very high prevalence of AUD in this population

• M-SASQ results in far more false positives than FAST

• M-SASQ is far less efficient at identifying high risk alcohol users

The criminal Justice SettingSensitivity, the efficiency in identifying true cases

M-SASQ FAST

M-SASQ has a sensitivity of 81.3% and FAST 92.1%. FAST is significantly more efficient at identifying true positives.

The criminal Justice SettingOdds ratio favouring fast for different outcomes

AUDIT +ve

The odds of being a true positive after scoring positive on FAST is 2.6 times that after scoring positive on M-SASQ, the odds of being categorised as increasing risk is similar for both instruments, but M-SASQ significantly under-estimates high risk individuals (OR 1.58).

Increasing Risk

High Risk

The Emergency Department SettingUniversal M-SASQ and FAST. Targeted PAT

• Higher prevalence than population norm but not as high as CJS

• High risk consumers are more likely to be active consumers of alcohol than in CJS

• M-SASQ is the most efficient screening method in all respects

The Emergency Department SettingSensitivity and odds ratios

• Sensitivity is similar across all screens but the screen conversion rate, screen positives from those that approached was significantly better for M-SASQ.

• M-SASQ and FAST are significantly better at identifying AUDIT positive than PAT.

• M-SASQ is significantly better at identifying increasing risk than PAT

The Primary Care SettingComparing M-SASQ with FAST….

• Lowest prevalence of all the study settings.

• M-SASQ is significantly less sensitive than FAST.

• Other studies report that about 8-10% of primary care population are heavy episodic alcohol users but do not have an alcohol use disorder.

The Primary Care SettingSensitivity and odds ratios

• Sensitivity of FAST is significantly better than M-SASQ

• FAST is significantly better at identifying AUDIT positives but not significantly better than M-SASQ in terms of increasing or high risk differentiation.

The Primary Care SettingComparing targeted versus universal screening

• There are no interactions between screening method and screening approach

• Targeting results in significantly more screen positives

• Targeting is no more sensitive than universal screening

The Primary Care SettingSensitivity and odds ratios

• Sensitivity of targeted screening is similar to universal screening

• Targeted screening has higher odds ratios for AUDIT positive, increasing risk and high risk than universal screening but these are not significantly better.

What does it all mean?First the caveats…

• The data presented needs further detailed analysis

• The data needs modeling to take account of the clustered data

• A concurrent economic analysis will evaluate the cost-efficiency

What does it all mean?The populations….

• There are interesting differences between the population demographics in each study.

• CJS is younger (31 years), male (85%) and less stable. PHC is older (50 years), Female (52%) and the most stable. ED has the most variation in age and stability.

• CJS has the highest prevalence of AUD (c.65%+) and particular high risk AUD. ED has the next highest prevalence (c.45%) and PHC the lowest (c.28%)

• But ED has the highest prevalence of heavy episodic drinking.

• Each study appears to have elements of a distinct population.

What does it all mean?The screening tools….

• FAST is the most efficient screening tool in both PHC and CJS settings, in both settings M-SASQ is associated with more false positives and fewer true positives for high risk drinking.

• M-SASQ is the most efficient screening tool in ED settings in terms of the number of positives identified for the numbers approached.

• In ED settings M-SASQ is as efficient as FAST and both FAST and M-SASQ are more efficient than PAT in terms of diagnostic accuracy.

What does it all mean?Targeting versus universal….

• PAT is the least efficient screening tool in ED.

• In PHC targeting has a significantly better screen conversion rate than universal screening.

• In PHC targeting is no more efficient than universal screening in terms of diagnostic accuracy.

• Almost 50% of PHC presentations in the universal arm do not meet the targeted criteria.

• The most common targeted condition is hypertension and the second new registrations.

Thank you