Implications of enrolment eligibility criteria in alcohol treatment outcome research: generalisability and potential bias in 1- and 6-year outcomes
2014 (English)In: Drug and Alcohol Review, ISSN 0959-5236, E-ISSN 1465-3362, Vol. 33, no 6, 604-611 p.Article in journal (Refereed) Published
It has been acknowledged that participants in clinical trials differ from real-world service users,primarily due to the extensive use of research eligibility criteria (EC). Generalisability and outcome bias become pressing issueswhen evidence-based treatment guidelines, crystallised from outcome research, influence treatment provision.This study reportson the effects of EC on generalisability and short- and long-term outcomes among real-world treatment-seekers.
Ten of the most commonly used EC were operationalised and applied to a large representative service user sample(n = 1125) from Stockholm County, Sweden, to determine the percentage of real-world problem alcohol users that would havebeen excluded by each EC and the extent to which EC bias the 1 and 6-year alcohol outcomes.
Individual EC excluded between 5% and 80% of real-world service users and 96% would have been excluded by at least one EC. Most of the EC introduced a positive/upwards bias in 1- and 6-year outcomes. Most notably, the removal of the unmotivated/non-compliantservice users caused an upwards bias that would considerably boost estimates of treatment effectiveness. Other bias effects weresmaller. Six-year effects were generally higher than for 1 year.
Outcome studies that excludecomplex and non-compliant cases are not representative of real-world service users, and thus effectiveness estimates from clinicaltrials are biased by several commonly used EC.EC should be used judiciously and be taken into account in practice guidelines.This burgeoning research area should be further developed. [Storbjörk J. Implications of enrolment eligibility criteria inalcohol treatment outcome research: Generalisability and potential bias in 1- and 6-year outcomes.
Place, publisher, year, edition, pages
2014. Vol. 33, no 6, 604-611 p.
substance abuse treatment, eligibility criteria, research design, representativeness, outcome bias
IdentifiersURN: urn:nbn:se:su:diva-108240DOI: 10.1111/dar.12211ISI: 000345232100006OAI: oai:DiVA.org:su-108240DiVA: diva2:756009
FunderForte, Swedish Research Council for Health, Working Life and Welfare, 2006-0822 & 2013-2855