Cumberland Ankle Instability Tool (CAIT)

The Cumberland Ankle Instability Tool (CAIT) is a self-reported questionnaire designed to measure the degree of functional ankle instability in patients. It consists of nine items that together provide a total score of 30【1】.

CAIT was specifically developed to distinguish between stable and unstable ankles using numerical values, making it an effective tool for both diagnosis and follow-up【2】.

Target Population

CAIT was developed for individuals with chronic ankle instability (CAI).

• Proven validity and reliability make it suitable for monitoring changes in stability over time【1】.

Administration and Method

• The CAIT questionnaire is self-administered.

• Patients rate the level of difficulty experienced during daily or sports-related activities.

• Each ankle is assessed separately, allowing for individual evaluation of the left and right side【2】.

Scoring and Interpretation

• 0 points: Severe functional ankle instability

• 30 points: Completely stable ankle

Cut-off values:

• Original threshold: ≤27 suggests chronic ankle instability【1】.

• Updated research: ≤25 improves diagnostic accuracy【10】.

Psychometric Properties

CAIT demonstrates strong measurement properties:

• Test–retest reliability: ICC2,1 = 0.96 → excellent consistency【1】.

• Sensitivity: 82.9% → effective at identifying CAI【1】.

• Specificity: 74.7% → effective at excluding healthy individuals【1】.

• Minimal Detectable Change (MDC): ≥3.08 points【11】.

• Minimal Clinically Important Difference (MCID): ≥3 points → indicates meaningful clinical change【11】.

CAIT combines high validity, reliability, and responsiveness, making it one of the most widely used self-reported tools for functional ankle instability.

Conclusion

The Cumberland Ankle Instability Tool (CAIT) is a simple, quick, and highly reliable tool for assessing functional ankle instability.

It is strongly recommended for use in clinical diagnosis, follow-up, and research, as it provides valuable insights into the patient’s perceived ankle function and stability over time.

Sources:

1. Hiller CE, Refshauge KM, Bundy AC, Herbert RD, Kilbreath SL. The Cumberland ankle instability tool: a report of validity and reliability testing. Archives of Physical Medicine and Rehabilitation. 2006;87(9):1235-1241.

2. Vuurberg G, Kluit L, van Dijk CN. The Cumberland Ankle Instability Tool (CAIT) in the Dutch population with and without complaints of ankle instability. Knee Surgery, Sports Traumatology, Arthroscopy. 2018;26:882-891.

3. De Noronha M, Refshauge KM, Kilbreath SL, Figueiredo VG. Cross-cultural adaptation of the Brazilian-Portuguese version of the Cumberland Ankle Instability Tool (CAIT). Disability and Rehabilitation. 2008;30(26):1959-1965.

4. Wang W, Liao D, Kang X, Zheng W, Xu W, Chen S, Xie Q. Development of a valid Chinese version of the Cumberland Ankle Instability Tool in Chinese-speaking patients with chronic ankle instability disorders. Scientific Reports. 2021;11(1):1-8.

5. Geerinck A, Beaudart C, Salvan Q, Van Beveren J, D’Hooghe P, Bruyère O, Kaux JF. French translation and validation of the Cumberland Ankle Instability Tool, an instrument for measuring functional ankle instability. Foot and Ankle Surgery. 2020;26(4):391-397.

6. Kunugi S, Masunari A, Noh B, Mori T, Yoshida N, Miyakawa S. Cross-cultural adaptation, reliability, and validity of the Japanese version of the Cumberland Ankle Instability Tool. Disability and Rehabilitation. 2017;39(1):50-58.

7. Ko J, Rosen AB, Brown CN. Cross‐cultural adaptation and validation of the Korean version of the Cumberland Ankle Instability Tool. International Journal of Sports Physical Therapy. 2015;10(7):1007.

8. Hadadi M, Ebrahimi Takamjani I, Ebrahim Mosavi M, Aminian G, Fardipour S, Abbasi F. Cross-cultural adaptation, reliability, and validity of the Persian version of the Cumberland Ankle Instability Tool. Disability and Rehabilitation. 2017;39(16):1644-1649.

9. Cruz-Díaz D, Hita-Contreras F, Lomas-Vega R, Osuna-Pérez MC, Martínez-Amat A. Cross-cultural adaptation and validation of the Spanish version of the Cumberland Ankle Instability Tool (CAIT): an instrument to assess unilateral chronic ankle instability. Clinical Rheumatology. 2013;32:91-98.

10. Wright CJ, Arnold BL, Ross SE, Linens SW. Recalibration and validation of the Cumberland Ankle Instability Tool cutoff score for individuals with chronic ankle instability. Archives of Physical Medicine and Rehabilitation. 2014;95(10):1853-1859.

11. Wright CJ, Linens SW, Cain MS. Establishing the minimal clinical important difference and minimal detectable change for the Cumberland Ankle Instability Tool. Archives of Physical Medicine and Rehabilitation. 2017;98(9):1806-1811.