Validity, reliability, and responsiveness of a self-reported foot and ankle score (SEFAS)

Abstract

Background and purpose A questionnaire was introduced by the New Zealand Arthroplasty Registry for use when evaluating the outcome of total ankle replacement surgery. We evaluated the reliability, validity, and responsiveness of the modified Swedish version of the questionnaire (SEFAS) in patients with osteoarthritis or inflammatory arthritis before and/or after their ankle was replaced or fused.Patients and methods The questionnaire was translated into Swedish and cross-culturally adapted according to a standardized procedure. It was sent to 135 patients with ankle arthritis who were scheduled for or had undergone surgery, together with the foot and ankle outcome score (FAOS), the short form 36 (SF-36) score, and the EuroQol (EQ-5D) score. Construct validity was evaluated with Spearman’s correlation coefficient when comparing SEFAS with FAOS, SF-36, and EQ-5D, content validity by calculating floor and ceiling effects, test-retest reliability with intraclass correlation coefficient (ICC), internal consistency with Cronbach’s alpha (n = 62), agreement by Bland-Altman plot, and responsiveness by effect size and standardized response mean (n = 37).Results For construct validity, we correlated SEFAS with the other scores and 70% or more of our predefined hypotheses concerning correlations could be confirmed. There were no floor or ceiling effects. ICC was 0.92 (CI 95%: 0.88–0.95), Cronbach’s alpha 0.96, effect size was 1.44, and the standardized response mean was 1.00.Interpretation SEFAS is a self-reported foot and ankle score with good validity, reliability and responsiveness, indicating that the score can be used to evaluate patients with osteoarthritis or inflammatory arthritis of the ankle and outcome of surgery.

Patient-reported outcome measures in hallux valgus surgery. A review of literature

“…A relative drawback of the MOXFQ consists of the copyright licence, which is required for any use of the score, with administration fees for any version [52]. Limited validated translations of both instruments have been developed until now [48,53]. The psychometric properties of the quality of life scores, demonstrate the SF-36 meets quality criteria best.…”

“…It consists of 12 items, with 3 subscales (pain, function and additional symptoms) [48]. Eight questions are derived from the Oxford-12-hip questionnaire; 4 questions are focussed on foot/ankle pathology [39].…”

Surgery for adult acquired flatfoot due to posterior tibial tendon dysfunction reduces pain, improves function and health related quality of life

“…Surgery becomes an option after failed non-surgical treatment. There are less than 20 published studies that evaluate the outcome of this type of surgery, most are small retrospective investigations [11][12][13][14][15][16][17][18][19] with only postoperative data presented [23][24][25][26] and only few use a prospective design [20][21][22]. The aim of this study was to prospectively evaluate surgery for stage II AAFD.…”

Re: “The impact of ankle osteoarthritis. The difference of opinion between patient and orthopedic surgeon” [Foot Ankle Surg. 20 (2014) 241–247]

“…In our first study published 2012 we found that SEFAS has good psychometric properties in patients with inflammatory arthritis and osteoarthritis in the ankle [2]. This study was presented by M. Cö ster at the 9th International Congress of the European Foot and Ankle Society in Noodwijk, Netherlands in September 2012.…”

“…We find it remarkable that the authors claim that such a PROM does not exist. Three papers concerning the Self-reported Foot and Ankle score (SEFAS) has been published by our group [2][3][4] and one based on the New Zealand Joint Registry [5]. At least two of these four papers were available when the paper by Witteveen was accepted in May 2014.…”