Aims

The Manchester-Oxford Foot Questionnaire (MOxFQ) is an anatomically specific patient-reported outcome measure (PROM) currently used to assess a wide variety of foot and ankle pathology. It consists of 16 items across three subscales measuring distinct but related traits: walking/standing ability, pain, and social interaction. It is the most used foot and ankle PROM in the UK. Initial MOxFQ validation involved analysis of 100 individuals undergoing hallux valgus surgery. This project aimed to establish whether an individual’s response to the MOxFQ varies with anatomical region of disease (measurement invariance), and to explore structural validity of the factor structure (subscale items) of the MOxFQ.

The patient-reported Manchester-Oxford Foot Questionnaire (MOXFQ), with 3 dimensions (Walking/standing(W/S), Pain, Social interaction(SI)) has previously been validated in patients undergoing hallux valgus surgery. A preliminary cross-sectional evaluation of its measurement properties relating to surgery on different regions of the foot and ankle is presented here.

Within 4 weeks prior to foot or ankle surgery, 671of 764 consecutive eligible patients (87.8% response rate) were assessed with the: (i) MOXFQ questionnaire, (ii) SF-36 general health survey (iii) American Orthopaedic Foot & Ankle Society (AOFAS) scales. Sample characteristics: mean age 53 years 427 (63.6%) female. Patients were booked for (main) surgery on Hallux (210, 31.3%), Lesser Toes (119, 17.7%), Mid foot (22, 3.3%), Ankle/Hind foot (311, 46.3%) and whole foot/multiple regions (9, 1.3%)

MOXFQ item response rates were high (<2% missing on any one item) with responses generally well distributed across response categories. Item-total correlations within each dimension were generally above recommended levels. Internal consistency, as assessed by Cronbach's alpha, were 0.93, 0.84 and 0.71 for the W/S, Pain and SI dimensions, respectively. Within Hallux, Lesser toes and Ankle/hind foot surgical subgroups (low numbers precluded mid foot and whole/multiple region analyses), alphas for these subscales were similar. Convergent validity of MOXFQ was demonstrated by correlations between the 3 dimensions (W/S, Pain, SI) with similar dimensions of the SF-36 and relevant AOFAS scales. A priori hypotheses were generally supported.

The MOXFQ demonstrates good baseline measurement properties in patients undergoing a range of foot and ankle surgery, suggesting its suitability as an outcome measure for clinical trials of foot and ankle surgery in general. The SI dimension, concerned with cosmesis and social participation has somewhat weaker properties but remains useful. Evidence for the MOXFQ's responsiveness across the range of foot and ankle surgery is yet to be assessed.

We developed the Oxford ankle foot questionnaire to assess the disability associated with foot and ankle problems in children aged from five to 16 years. A survey of 158 children and their parents was carried out to determine the content, scaling, reliability and validity of the instrument. Scores from the questionnaire can be calculated to measure the effect of foot or ankle problems on three domains of children’s lives: physical, school and play, and emotional. Scores for each domain were shown to be internally consistent, stable, and to vary little whether reported by child or parent. Satisfactory face, content and construct validity were demonstrated. The questionnaire is appropriate for children with a range of conditions and can provide clinically useful information to supplement other assessment methods. We are currently carrying out further work to assess the responsiveness of questionnaire scores to change over time and with treatment.