Applicability of cutoff scores of Chinese Cumberland Ankle Instability Tool and Foot and Ankle Ability Measure as inclusion criteria for study of chronic ankle instability in Chinese individuals

Abstract

Objective: To examine the applicability of Chinese Cumberland Ankle Instability Tool (CAIT-C) and Foot and Ankle Ability Measure (FAAM-C) as inclusion criteria recommended by the International Ankle Consortium (IAC) for study of chronic ankle instability in the Chinese individuals.

Design: Cross-sectional comparative design with known groups.

Setting: Research laboratory.

Participants: 145 participants with chronic ankle instability (CAI) and 66 participants without injury.

Main outcome measures: CAIT-C and FAAM-C Activities of Daily Living (FAAM-C-ADL) and FAAM-C Sports (FAAM-C-Sports).

Results: The CAIT-C scores (18.2 ± 5.6), FAAM-C-ADL scores (97.0 ± 4.3) and FAAM-C-Sports scores (92.2 ± 10.3) of the CAI group were all lower than the CAIT-C scores (27.4 ± 3.1), FAAM-ADL scores (99.0 ± 2.1) and FAAM-Sports scores (98.4 ± 3.1) (P < 0.01) of the uninjured group. The recommended cutoff score of CAIT-C<24 by the IAC for identifying CAI had a sensitivity of 80.7% and a specificity of 84.9%. If the recommended cutoff scores of FAAM-ADL<90，FAAM-Sports<80 by the IAC as inclusion criteria for the study of CAI were applied, 97% of participants with CAI in this sample would be excluded.

Conclusion: The results support the recommended cutoff score of CAIT-C<24 by the IAC to identify Chinese individuals with CAI for study. However, the recommended cutoff scores of FAAM-ADL<90 and FAAM-Sports<80 will exclude most Chinese individuals with CAI having only mild functional impairments.

Keywords: Chronic ankle instability; Cumberland ankle instability tool; Foot and ankle ability measure; Lateral ankle sprain.