Visual Analogue Scale Foot and Ankle: Validity and Reliability of Thai Version of the New Outcome Score in Subjective Form
Chayanin Angthong MD*, Bancha Chernchujit MD*, Thongchai Suntharapa MD*, Thossart Harnroongroj MD**
Affiliation : * Department of Orthopaedic Surgery, Faculty of Medicine, Thammasat Hospital, Thammasat University, Pathum Thani, Thailand ** Department of Orthopaedic Surgery, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : Nowadays, measuring score in the form of subjective questionnaires is the important tool for clinical evaluation
of the foot and ankle-related problems. Visual Analogue Scale-Foot and Ankle (VAS-FA) is the newly developed subjective
questionnaire, which has sufficiency of validity and reliability from a previous study.
Objective : Translate the original English version of VAS-FA into the Thai version and evaluate the validity and reliability of
Thai VAS-FA in patients with foot and ankle-related problems.
Material and Method: According to the forward-backward translation protocol, original VAS-FA was translated into the
Thai version. Thai VAS-FA and validated Thai Short Form-36 (SF-36) questionnaires were distributed to 42 Thai patients to
complete. For validation, Thai VAS-FA scores were correlated with SF-36 scores. For reliability, the test-retest reliability and
internal consistency were analyzed.
Results : Thai VAS-FA score demonstrated the sufficient correlations with physical functioning (PF), role physical (RP), bodily
pain (BP) domains, and total score of SF-36 (statistically significant with p < 0.001 level and r > 0.5 values). The result of
reliability revealed highly intra-class correlation coefficient as 0.995 from test-retest study. The internal consistency was
excellent with Cronbach alpha: 0.995.
Conclusion : The original VAS-FA score is a well-validated, subjective, visual-analogue-scale based outcome score. The Thai
version of VAS-FA form maintained the validity and reliability of the original version. This newly translated-validated score
can be distributed for the evaluation of the functions, symptoms, and limitation of activities in Thai patients with foot and ankle
problems.
Keywords : Visual analogue scale-foot and ankle (VAS-FA), Outcome score, Validity, Reliability, Short form 36 general health outcome (SF-36), Questionnaire
