Understanding what works--and why--in quality improvement: the need for theory-driven evaluation.

Clinicians who are asked to participate in quality improvementprogrammes in healthcare organizations are often heard to askfor the evidence that they ‘work’. By that, theyoften mean they want randomized controlled trials, which showthat accreditation, or credentialing, or criterion-based audit,or adverse event monitoring, or continuous quality improvementprogrammes, or whatever approach is being used cause meaningfuland worthwhile improvements in the quality of care [1]. Whenthey learn that there are relatively few experimental studiesof quality improvement interventions [2], and those which doexist often show weak or moderate effects at best, this stateof affairs is sometimes used to argue that it is not worthwhile