Background Data about the frequency of foot problems in rheumatoid arthritis (RA) can be obtained through self-report or clinical examination. The level of agreement between these two approaches has not been established in RA.
Objectives To measure levels of agreement between self-report and clinical examination of foot problems in RA.
Methods A random sample of RA patients who had self-reported foot problems in a questionnaire underwent a structured foot examination and clinical interview conducted by a single observer (podiatrist). Data collected included: patient demographics and clinical characteristics; whether they had accessed foot care (AFC) services (podiatry, orthotics and/or orthopaedics); impact of foot problems (Foot Impact Scale: Impairment/Footwear (FISIF) and Activities/Participation (FISAP) subscales); and presence of foot problems on examination. Extent of agreement between self-report and clinical examination was measured by the kappa statistic (k).
Results Of 235 patients invited to participate, 110 (47%) attended; 65 AFC (59%); 77 Female (70%); mean (SD) age 63.1 (11.2) years; median (IQR) disease duration 8.5 (1, 51) years; HAQ 1.25 (0.375, 2.00); FISIF 9 (5, 13); and FISAP 15 (3, 22).
The overall frequency of reported and examined foot problems were: toe deformities - 66% and 69%; hallux valgus - 35% and 33%; pes planus - 26% and 56%; callus - 56% and 53%; corns - 12% and 12%; blisters - 5% and 2%; thickened toe-nails - 57% and 45%: ingrown toe-nails - 16% and 15%; joint swelling - 28% and 65%; nodules - 23% and 16%; numbness - 27% and 19%.
High agreement occurred for: corns (98%, k=0.913); ingrown toe-nails (97%, k=0.893); and hallux valgus (98%, k=0.959); nodules (92%, k=0.724); callus (84%, k=0.670); toe deformities (86%, k=0.67); and thickened toe nails (80%, K=0.606). Fair agreement was detected for numbness and pes planus (79%, k=0.418 and 76%, k=0.377) but only chance agreement for joint swelling (49%, k<0.01).
Conclusions Overall, high levels of agreement were detected between self-report and clinical examination for many foot problems, suggesting self-report can be utilised with a high degree of confidence. However, levels of agreement for more complex foot problems (e.g. pes planus) were only fair and patients substantially under-reported features of disease activity (e.g. joint swelling), indicating that clinical examination is required for these features.
Disclosure of Interest None declared
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.