South African clinical practice guidelines quality measured with complex and rapid appraisal instruments

Background: Critically appraising the quality of clinical practice guidelines (CPGs) is an essential element of evidence implementation. Critical appraisal considers the quality of CPG construction and reporting processes, and the credibility of the body of evidence underpinning recommendations. To date, the focus on CPG critical appraisal has come from researchers and evaluators, using complex appraisal instruments. Rapid critical appraisal is a relatively new approach for CPGs, which targets busy end-users such as service managers and clinicians. This paper compares the findings of two critical appraisal instruments: a rapid instrument (iCAHE) and a complex instrument (AGREE II). They were applied independently to 16 purposively-sampled, heterogeneous South African CPGs, written for eleven primary health care conditions/health areas. Overall scores, and scores in the two instruments' common domains Scope and Purpose, Stakeholder involvement, Underlying evidence/Rigour of Development, Clarity), were compared using Pearson r correlations and intraclass correlation coefficients. CPGs with differences of 10 % or greater between scores were identified and reasons sought for such differences. The time taken to apply the instruments was recorded. 

Results: Both instruments identified the generally poor quality of the included CPGs, particularly in Rigour of Development. Correlation and agreement between instrument scores was moderate, and there were no overall significant score differences. Large differences in scores for some CPGs could be explained by differences in instrument construction and focus, and CPG construction. The iCAHE instrument was demonstrably quicker to use than the AGREE II instrument. 

Conclusions: Either instrument could be used with confidence to assess the quality of CPGs. The choice of appraisal instrument depends on the needs and time of end-users. Having an alternative (rapid) critical appraisal tool will potentially encourage busy end-users to identify and use good quality CPGs to inform practice decisions.