Systematic review and meta-analysis of the reproducibility of patient self-reported joint counts in rheumatoid arthritis
Objective To assess the reproducibility of patient-reported tender and swollen joint counts of RA patients compared to trained clinicians. Methods We conducted a systematic literature review and meta-analysis of studies comparing patient-reported tender and/or swollen joint counts (TJC and SJC) to clinician counts in patients with rheumatoid arthritis. We calculated a pooled summary estimates for correlation. Agreement was compared using a Bland and Altman approach. Results 14 studies were included in the meta-analysis. There were strong correlations between clinician and patient TJC, 0.78 (95% CI: 0.76, 0.80), and clinician and patient SJC, 0.59 (95% CI: 0.54, 0.63). TJC had good reliability ranging from 0.50 to 0.85. SJC had moderate reliability ranging from 0.28 to 0.77. Agreement for TJC reduced for higher TJC values, suggesting a positive bias for self-reported TJC, which was not observed for SJC. Conclusion This meta-analysis has identified a strong correlation for patient-reported and clinician TJC, and a moderate correlation for SJC. Patient-reported joint counts may be suitable for use in annual review for patients in remission and in monitoring treatment response for patients with rheumatoid arthritis. However, they are likely not appropriate for decisions on commencement of biologics. Further research is needed to identify patient groups where patient-reported joint counts are unsuitable.