The clinical and cost effectiveness of shoe inserts in people with established rheumatoid arthritis

INTERVENTION: Two foot orthoses were prescribed over 16 weeks and included: (1) Custom‐made foot orthoses and (2) simple insoles. The custom‐made foot orthoses were manufactured from high density ethyl vinyl acetate, with a thickness of 20mm and a shore density of 50, a contoured medial arch, high heel cup and external medial posting correction customised to each patient according to the amount of valgus rearfoot deformity present and maximum forefoot balancing technique, determined by the external manufacturer providing the interventions (Langer Biomechanics Group, Cheadle, UK). All foot orthoses were covered with 1.6mm cushioning material extending the length of the foot. The simple insoles were a simple 6mm cushioning insole made from a breathable foam core on a rubber‐silicone‐ethylene compound, cut to fit the exact shape of the participants’ footwear. Both interventions were the same top colour. Each participant was asked to wear the foot orthoses or simple insole as frequently as possible. Each participant completed a diary with the number of hours worn during the week and any adverse events. CONDITION: rheumatoid arthritis PRIMARY OUTCOME: Foot Pain. Foot pain was measured using the Foot Function Index. The Foot function Index is a self‐administered questionnaire consisting of 23‐items grouped in three domains: foot pain (nine items), disability (nine items) and functional limitation (five items). Higher scores indicate greater pain, disability and limitation of activity and thus poorer foot health. We estimated the effects on health related quality of life (utilities) of the intervention and the control and undertook a cost‐utility analysis using QALYs as the measure of effect. We estimated participant utilities by administering the EQ5D instrument at baseline and 16 weeks; combined them with the area under the curve method to calculate QALY gains over the 16 week study period; and corrected for baseline EQ5D. We estimated the cost per QALY gain by dividing differences in cost by differences in QALYs and compared by the thresholds recommended by NICE SECONDARY OUTCOME: Foot impairment. Foot impairment was used using the Foot Function Index. INCLUSION CRITERIA: Participants were eligible if they were over 18 years old, history of foot pain, ability to walk a required distance of 5 metres for measurement of foot function and had a diagnosis of RA according to the American Rheumatism Association revised criteria.