['Fitting' evidence preferable when evaluating effectiveness of interventions].

The Dutch Health Care Insurance Board (CVZ) and the Institute for Medical Technology Assessment have developed a questionnaire to help assessors to formulate an answer to the question of which evidence fits best when evaluating the effectiveness of interventions by medical specialists. The Feasible Information Trajectory (FIT) questionnaire is based on the idea that the clinical setting defines the attainable study characteristics and thus possibly available evidence. The FIT questionnaire focuses on study characteristics (randomization, blinding and control groups) and not on study type (e.g. RCT, cohort) as is common within evidence-hierarchy grading systems. Together these attainable characteristics define the most -fitting evidence. The questionnaire should be filled in prior to the literature assessment. Subsequently the most-fitting evidence profile can be modified on the basis of a literature assessment and possibly arguments put forward by healthcare professionals. Filling out the FIT questionnaire is therefore not a static exercise but is part of the search for all relevant arguments in the assessment of effectiveness.