Ankle Fractures, Ankle Injuries
Conditions
Keywords
patient-reported outcome measure, PROM, cross-cultural adaptation, psychometric validation, ankle fracture, rehabilitation, Rasch analysis, Turkish
Brief summary
Ankle fractures are common injuries that can affect a patient's mobility, mood, sleep, and everyday life for months. The Ankle Fracture Outcome of Rehabilitation Measure (A-FORM) is an English-language patient-reported outcome measure developed in Australia to capture this broader rehabilitation experience. No validated Turkish version of A-FORM currently exists. This prospective multi-centre observational study aims to translate the A-FORM into Turkish (A-FORM-TR), culturally adapt it for use in Turkish-speaking patients, and evaluate its psychometric properties. The investigators will recruit 150 adults with a unilateral ankle fracture, treated either surgically or conservatively, from three orthopedic centres in Turkiye and the Turkish Republic of Northern Cyprus. Participants complete the A-FORM-TR together with two established comparator questionnaires (AOFAS Ankle-Hindfoot Score and the Turkish Olerud-Molander Ankle Score). A subset of approximately 50 participants is re-administered the A-FORM-TR after 7 to 14 days to assess test-retest reliability, with a Global Rating of Change item identifying clinically stable patients. Analyses include classical test theory, confirmatory factor analysis, and Rasch measurement analysis.
Detailed description
Background and Rationale: Ankle fractures are among the most common lower-limb injuries in orthopedic practice. Patient-reported recovery, including physical function, sleep, mood, and social participation, is not adequately captured by traditional clinician-based outcome measures such as the AOFAS Ankle-Hindfoot Score or the Olerud-Molander Ankle Score. The A-FORM, developed by McPhail et al. (2014), is a 15-item, Rasch-calibrated patient-reported outcome measure designed specifically to evaluate the rehabilitation experience after ankle fracture. No validated Turkish-language version currently exists. Methodological Framework: The study follows the eight-stage cross-cultural adaptation and validation protocol described by Cruchinho et al. (2024), which incorporates the recommendations of Beaton et al. (2000) and the COSMIN framework (Mokkink et al., 2010). Written permission to translate and use the instrument has been granted by Prof. Steven McPhail (Queensland University of Technology). Translation and Adaptation: Forward translation is carried out by two independent bilingual translators (one faculty member from the Department of English Language and Literature, providing linguistic expertise; one bilingual orthopedic surgeon, providing clinical content expertise). A reconciliation committee produces a synthesised Turkish version, which is then back-translated by two independent translators blinded to the original. A harmonisation expert committee compares the source, forward, and back versions for semantic, idiomatic, experiential, and conceptual equivalence. The harmonised pre-test version is evaluated through cognitive debriefing interviews with 10 to 15 ankle-fracture patients before field testing. Field Testing: In the field testing phase, 150 adult patients with a radiographically confirmed unilateral ankle fracture (Weber A, B, or C; treated surgically by open reduction and internal fixation or conservatively with cast, walker boot, or functional brace) are enrolled across three orthopedic centres. Patients between 3 weeks and 12 months post-injury are eligible. The A-FORM-TR is administered together with the AOFAS Ankle-Hindfoot Score and the OMAS-TR. A sub-cohort of approximately 50 patients is re-administered the A-FORM-TR at 7 to 14 days, with a Global Rating of Change item used to identify clinically stable patients for the test-retest reliability analysis. Statistical Analysis Plan: The analysis plan was locked before any field data were collected; all decision rules are pre-specified. Developed in consultation with the institutional biostatistics team. Internal consistency is assessed by Cronbach's alpha (target greater than or equal to 0.80). Test-retest reliability is assessed by the intraclass correlation coefficient on stable patients, reported with the K-index (greater than or equal to 0.70 acceptable for group-level comparison, greater than or equal to 0.90 desirable for individual-level decisions). Measurement error is evaluated separately from reliability as the standard error of measurement and the smallest detectable change. Rasch measurement analysis is the primary framework and examines item fit, threshold ordering, person separation reliability, person-item targeting, local independence, unidimensionality, and differential item functioning by sex, age group, treatment modality, recruiting centre, and time since injury; pre-specified decision rules govern the handling of item misfit, disordered thresholds and differential item functioning. Confirmatory factor analysis provides a complementary structural test of the prespecified single-factor model, with exploratory factor analysis run as a supplementary check. Construct validity is assessed via pre-specified hypotheses about correlation patterns with the AOFAS and OMAS-TR, and by known-groups comparison across time-since-injury strata. Criterion validity is assessed in a bilingual sub-study of approximately 30 participants completing both the A-FORM-TR and the original English-language A-FORM in counterbalanced order, with agreement quantified by correlation, intraclass correlation and Bland-Altman analysis. Responsiveness is assessed at 3 months against a Global Rating of Change anchor using the standardised response mean (SRM), effect size and receiver operating characteristic (ROC) analysis, with the minimal important change compared against the smallest detectable change. Cross-cultural measurement invariance is examined against the original English calibration, conditional on the source data available from the instrument developer. Content validity is assessed via item-level and scale-level Content Validity Index and the Kappa coefficient from the expert committee. Floor and ceiling effects are examined at the scale level. Missing data are reported per item; the primary analysis is complete-case, with multiple imputation as a sensitivity analysis where item-level missingness exceeds 5 percent.
Interventions
None listed
Sponsors
Utku Gürhan
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age 18 years or older * Radiographically confirmed unilateral ankle fracture (Weber A, B, or C) * Either surgical (open reduction and internal fixation) or conservative (cast, walker boot, or functional brace) treatment completed * Currently in the rehabilitation phase, 3 weeks to 12 months post-injury * Native Turkish speaker, able to read and self-complete a questionnaire * Able and willing to provide written informed consent
Exclusion criteria
* Bilateral ankle fracture * Previous ipsilateral ankle fracture or any prior orthopedic surgery on the same ankle * Pathological fracture (tumour, metastasis, or other underlying bone pathology) * Concurrent significant ipsilateral lower-limb injury (for example pilon fracture, ipsilateral tibial or fibular shaft fracture, ipsilateral femoral or tibial plateau fracture) * Polytrauma (significant head, spine, abdominal, or contralateral lower-limb injury affecting function) * Cognitive or psychiatric impairment precluding self-completion of the questionnaire * Insufficient Turkish literacy * Inability to attend a follow-up visit for the test-retest assessment
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Internal consistency of the A-FORM-TR | At the single study visit (baseline administration) | Cronbach's alpha coefficient calculated across all scored items of the A-FORM-TR. Target greater than or equal to 0.80. |
| Test-retest reliability of the A-FORM-TR | Second administration at day 7 and third administration at day 14 after baseline | Intraclass correlation coefficient (two-way mixed effects, absolute agreement, single measures) calculated for the A-FORM-TR Summary Score, restricted to patients reporting clinical stability (no change) on a Global Rating of Change item. The K-index of agreement is reported alongside the ICC. Thresholds: greater than or equal to 0.70 acceptable for group-level comparison; greater than or equal to 0.90 desirable for individual-level decisions. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Rasch model fit of the A-FORM-TR | At the single study visit (baseline administration) | Rasch measurement analysis serves as the primary framework for evaluating dimensionality and measurement properties of the A-FORM-TR. Examined: item fit (infit and outfit mean-square 0.5 to 1.5), category threshold ordering, person separation reliability (target greater than or equal to 2.0), local independence (residual correlations less than 0.30), unidimensionality (residual principal component analysis first contrast less than 2.0), and differential item functioning by sex, age group, treatment modality, centre, and time since injury. A priori decision rules: items showing substantive misfit will be reviewed for rescoring or removal; disordered thresholds will trigger response category collapsing and re-analysis; items showing significant DIF will be split or removed and the analysis re-run on the modified scale. |
| Structural validity by confirmatory factor analysis | At the single study visit (baseline administration) | Confirmatory factor analysis testing the prespecified single-factor (unidimensional) structure established in the original A-FORM development by McPhail et al. (2014). CFA serves as a complementary structural check from a latent-variable perspective alongside the primary Rasch analysis. Model fit assessed by CFI and TLI (target greater than or equal to 0.95), RMSEA (target less than or equal to 0.08), and SRMR (target less than or equal to 0.08). |
| Construct validity assessed by a priori hypothesis testing | At the single study visit (baseline administration) | Pearson or Spearman correlations between the A-FORM-TR Summary Score and the AOFAS Ankle-Hindfoot Score and OMAS-TR. Pre-specified hypotheses: H1, strong positive correlation between A-FORM-TR and OMAS-TR (r greater than or equal to 0.60); H2, moderate positive correlation between A-FORM-TR and AOFAS (r between 0.40 and 0.60); H3, the psychosocial items of the A-FORM-TR correlate more weakly with the AOFAS than the physical-function items. Construct validity is considered supported if at least 75 percent of the a priori hypotheses are confirmed. |
| Content validity of the A-FORM-TR | Pre-testing phase, prior to field testing | Item-level and scale-level Content Validity Index and the Kappa coefficient of agreement derived from the expert committee evaluation conducted in the pre-testing phase. |
| Distribution properties: floor and ceiling effects | At the single study visit (baseline administration) | Percentage of participants scoring at the floor (lowest possible score) and ceiling (highest possible score) of the A-FORM-TR Summary Score. Effects are considered acceptable if less than 15 percent at either extreme. |
| Known-groups validity by time since injury and treatment modality | At the single study visit (baseline administration) | Known-groups validity assessed by testing whether A-FORM-TR Summary Scores differ across pre-specified clinical subgroups. Pre-specified hypotheses: H4, patients in the 3-week to 3-month post-injury subgroup will score significantly lower (greater impairment) than patients in the 6- to 12-month subgroup; H5, A-FORM-TR Summary Scores will differ between surgically treated and conservatively treated patients (no a priori directional hypothesis). Analyses by independent-samples t-test or Mann-Whitney U as appropriate, with Cohen's d or effect size reporting. Added in response to peer review feedback from the original instrument developer. |
| Measurement error of the A-FORM-TR | Between baseline and the day 14 administration | Standard error of measurement (SEM) derived from the test-retest data, and the smallest detectable change (SDC) calculated as 1.96 x square root of 2 x SEM. Bland-Altman plots with limits of agreement are reported. Measurement error is evaluated as a property distinct from reliability, in line with the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) framework. |
| Responsiveness of the A-FORM-TR | Baseline and 3 months | Ability of the A-FORM-TR to detect change over time, assessed against an anchor. Change scores from baseline to 3 months are correlated with a single-item Global Rating of Change (expected r greater than or equal to 0.50). The standardised response mean (SRM) and effect size are computed separately in patients reporting improvement and in those reporting no change (expected SRM greater than or equal to 0.80 versus less than 0.20). Discrimination between improved and stable patients is assessed by receiver operating characteristic (ROC) analysis, with the area under the curve (AUC) expected to be greater than or equal to 0.70. The minimal important change derived from the ROC optimal cut-point is compared against the smallest detectable change. |
| Criterion validity against the original English A-FORM | Baseline (Day 1); both language versions administered in the same session, at least 30 minutes apart | In a bilingual sub-study of approximately 30 Turkish Cypriot participants who are functionally literate in both Turkish and English, both the A-FORM-TR and the original English-language A-FORM are administered in counterbalanced order with at least 30 minutes between administrations. Agreement between the two language versions is assessed by Pearson or Spearman correlation (expected r greater than or equal to 0.80), intraclass correlation coefficient (expected greater than or equal to 0.80), and Bland-Altman analysis to detect systematic differences. Bilingual eligibility requires documented criteria beyond self-report. This subgroup is not representative of the main sample and this is reported as a limitation. |
| Cross-cultural measurement invariance | At the single study visit (baseline administration) | Comparison of the Turkish item calibration against the original English-language calibration reported by McPhail et al. 2014. The analysis is conditional on the level of source data available from the instrument developer: with raw item-level data, multi-group confirmatory factor analysis testing configural, metric and scalar invariance; with item difficulty estimates only, anchored Rasch calibration with comparison of item difficulty hierarchies. If neither is available, within-sample differential item functioning by sex, age group, treatment modality, recruiting centre and time since injury is reported together with a descriptive comparison against the published psychometric profile. |
Countries
Cyprus, Turkey (Türkiye)
Contacts
CONTACTUtku Gurhan, MD
PRINCIPAL_INVESTIGATORUtku Gurhan, MD
University of Kyrenia
Outcome results
None listed