Reliability and validity of the Dutch version of the foot and ankle outcome score (FAOS)

Abstract

BackgroundThe Foot and Ankle Outcome Score (FAOS) is a patient-reported questionnaire measuring symptoms and functional limitations of the foot and ankle. Aim is to translate and culturally adapt the Dutch version of the FAOS and to investigate internal consistency, validity, repeatability and responsiveness.MethodsAccording to the Cross Cultural Adaptation of Self-Report Measures guideline, the FAOS was translated into Dutch. Eighty-nine patients who had undergone an ankle arthroscopy, ankle arthrodesis, ankle ligament reconstruction or hallux valgus correction completed the FAOS, FFI, WOMAC and SF-36 questionnaires and were included in the validity study. Sixty-five of them completed the FAOS a second time to determine repeatability. Responsiveness was analysed in an additional 15 patients who were being treated for foot or ankle problems.ResultsInternal consistency of the FAOS is high (Cronbach’s alphas varying between 0.90 and 0.96). Repeatability can be considered good, with ICC’s ranging from 0.90 to 0.96. Construct validity can be classified as good with moderate-to-high correlations between the FAOS subscales and subscales of the FFI (0.55 to 0.90), WOMAC (0.57 to 0.92) and SF-36 subscales physical functioning, pain, social functioning and role-physical (0.33 to 0.81). Low standard response means were found for responsiveness (0.0 to 0.4).ConclusionsThe results of this study show that the Dutch version of the FAOS is a reliable and valid questionnaire to assess symptoms and functional limitations of the foot and ankle.

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

“…It has been validated in the original manuscript, on patients after ankle ligament reconstruction. Recently it has been validated for patients with hallux valgus, showing acceptable reliability and responsiveness [45,46]. However, the sports and recreation subscale of the FAOS showed little responsiveness to hallux valgus surgery.…”

Psychometric Properties of the Foot and Ankle Outcome Score in a Community‐Based Study of Adults With and Without Osteoarthritis

“…The Foot and Ankle Outcome Score (FAOS) consists of 42 items as effect indicators for 5 subscales of pain, other symptoms, activities of daily living (ADL), sport and recreational function (sport/recreation), and foot‐ and ankle‐related quality of life (QOL). In patient samples, the FAOS was validated among patients ages 20–60 years with lateral ankle instability (), and the validity (1 factor for each subscale) and reliability (Cronbach's α >0.7, test–retest intraclass correlation coefficients [ICCs] >0.7) of this instrument also have been confirmed among other patient samples with foot and ankle disorders (). The FAOS presents with several advantages as a valuable measure for a population‐based study.…”

The Munich Ankle Questionnaire (MAQ): a self-assessment tool for a comprehensive evaluation of ankle disorders

“…The majority of the patients obtained a poor test result indicating a high subjective burden. Analyzing the data of PROMs may, thus, be helpful to critically evaluate if operative procedures such as TKA are necessary and when the potential of conservative treatment might be exhausted [ 26 , 27 ]. By wide spread use, the introduced MAQ could serve for the same purpose regarding patients suffering from ankle disorders because it allows the assessment of the subjective (pain) and objective (movement and ROM) patient status.…”