More than one third of clinical practice guidelines on low back pain overlap in AGREE II appraisals. Research wasted?

BACKGROUND: Systematic reviews can apply the Appraisal of Guidelines for Research & Evaluation (AGREE) II tool to critically appraise clinical practice guidelines (CPGs) for treating low back pain (LBP); however, when appraisals differ in CPG quality rating, stakeholders, clinicians, and policy-makers will find it difficult to discern a unique judgement of CPG quality. We wanted to determine the proportion of overlapping CPGs for LBP in appraisals that applied AGREE II. We also compared inter-rater reliability and variability across appraisals. METHODS: For this meta-epidemiological study we searched six databases for appraisals of CPGs for LBP. The general characteristics of the appraisals were collected; the unit of analysis was the CPG evaluated in each appraisal. The inter-rater reliability and the variability of AGREE II domain scores for overall assessment were measured using the intraclass correlation coefficient and descriptive statistics. RESULTS: Overall, 43 CPGs out of 106 (40.6%) overlapped in seventeen appraisals. Half of the appraisals (53%) reported a protocol registration. Reporting of AGREE II assessment was heterogeneous and generally of poor quality: overall assessment 1 (overall CPG quality) was rated in 11 appraisals (64.7%) and overall assessment 2 (recommendation for use) in four (23.5%). Inter-rater reliability was substantial/perfect in 78.3% of overlapping CPGs. The domains with most variability were Domain 6 (mean interquartile range [IQR] 38.6), Domain 5 (mean IQR 28.9), and Domain 2 (mean IQR 27.7). CONCLUSIONS: More than one third of CPGs for LBP have been re-appraised in the last six years with CPGs quality confirmed in most assessments. Our findings suggest that before conducting a new appraisal, researchers should check systematic review registers for existing appraisals. Clinicians need to rely on updated CPGs of high quality and confirmed by perfect agreement in multiple appraisals. TRIAL REGISTRATION: Protocol Registration OSF: https://osf.io/rz7nh/ SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12874-022-01621-w.