Authors: Swain, I., Farmer, S.E., Wood, D. and Pandyan, A.D.
Systematic reviews are used to inform practice, and develop guidelines and protocols. A questionnaire to quantify the risk of bias in systematic reviews, the review paper assessment (RPA) tool, was developed and tested. A search of electronic databases provided a data set of review articles that were then independently reviewed by two assessors using the RPA. The inter-rater reliability was between moderate and good (j scores 0.46–0.95). Many reviews did not describe the purpose in terms of population, intervention, comparator and outcome measure (i.e. PICO format), making inter-rater agreement on this question difficult. The RPA discriminated between high-quality reviews and those with a risk of bias (e.g. inadequate reporting of search terms, lack of independent reviewing or inclusion of non-randomized-controlled trials). The RPA questionnaire was revised to ensure that questions (on the basis of clarity of purpose, extent of search, independence of reviewers, randomized-controlled trial inclusion and availability of data) had dichotomous answers so that the positive responses scored one. The risk of bias increases as the score reduces.