Generalizability of clinical research

A frequent criticism of published randomized, controlled trials (RCTs) is that interventions that are successful in the RCT setting, often with personnel who have time dedicated to the study and strictly defined patient inclusion/exclusion criteria, may not translate well to the real-world clinical setting. Generalizability is one facet of the CONSORT statement, which outlines quality standards for reporting of clinical trials.

A research methodology article in today's British Medical Journal, "Assessment of generalisability in trials of health interventions: suggested framework and systematic review" (Bonell C et al, 2006 Aug 12;333:346-9), addresses the issue of generalizability and makes recommendations for "systematic evaluation and reporting of applicability" for all studies of health interventions.

Using studies of HIV prevention as an example, the authors recommend that researchers include in their process explicit consideration of questions such as "Can the intervention be delivered elsewhere?" and "Does the intervention meet recipients' needs?"

The authors note potential tremendous contributions to clinical effectiveness if investigators elaborate "contextual determinants of success" for the health interventions they consider, and if systematic reviews address generalizability as one component of research assessment.