%0 Journal Article
%T Validation of the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale Dutch language version in patients with hindfoot fractures
%A A Siebe De Boer
%A Cornelis H Van der Vlies
%A Duncan E Meuffels
%A Esther M M Van Lieshout
%A Michael H J Verhofstad
%A P Ted Den Hoed
%A Wim E Tuinebreijer
%J -
%D 2017
%R 10.1136/bmjopen-2017-018314
%X Objectives The American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale is among the most used questionnaires for measuring functional recovery after a hindfoot injury. Recently, this instrument was translated and culturally adapted into a Dutch version. In this study, the measurement properties of the Dutch language version (DLV) were investigated in patients with a unilateral hindfoot fracture.

Design Multicentre, prospective observational study.

Setting This multicentre study was conducted in three Dutch hospitals.

Participants In total, 118 patients with a unilateral hindfoot fracture were included. Three patients were lost to follow-up.

Primary and secondary outcome measures Patients were asked to complete the AOFAS-DLV, the Foot Function Index and the Short Form-36 on three occasions. Descriptive statistics (including floor and ceiling effects), reliability (ie, internal consistency), construct validity, reproducibility (ie, test¨Cretest reliability, agreement and smallest detectable change (SDC)) and responsiveness were determined.

Results Internal consistency was inadequate for the AOFAS-DLV total scale (¦Á=0.585), but adequate for the function subscale (¦Á=0.863). The questionnaire had adequate construct validity (82.4% of predefined hypotheses were confirmed), but inadequate longitudinal validity (70.6%). No floor effects were found, but ceiling effects were present in all AOFAS-DLV (sub)scales, most pronounced from 6 to 24 months after trauma onwards. Responsiveness was only adequate for the pain and alignment subscales, with a SDC of 1.7 points.

Conclusions The AOFAS Ankle-Hindfoot Scale DLV has adequate construct validity and is reliable, making it a suitable instrument for cross-sectional studies investigating functional outcome in patients with a hindfoot fracture. The inadequate longitudinal validity and responsiveness, however, hamper the use of the questionnaire in longitudinal studies and for assessing long-term functional outcome.

Trial registration number NTR5613; Post-results
%U https://bmjopen.bmj.com/content/7/11/e018314