Validity and reliability of the Achilles tendon total rupture score

The best treatment of acute Achilles tendon rupture remains debated. Patient-reported outcome measures have become cornerstones in treatment evaluations. The Achilles tendon total rupture score (ATRS) has been developed for this purpose but requires additional validation. The purpose of the present study was to validate a Danish translation of the ATRS. The ATRS was translated into Danish according to internationally adopted standards. Of 142 patients, 90 with previous rupture of the Achilles tendon participated in the validity study and 52 in the reliability study. The ATRS showed moderately strong correlations with the physical subscores of the Medical Outcomes Study 36-item Short-Form Health Survey (r = .70 to .75; p < .0001) and Victorian Institute of Sports Assessment-Achilles questionnaire (r = .71; p < .0001). Test-retest of the ATRS showed no significant difference in the mean (2.41; p = .07). The limits of agreement were ±18.53. A strong correlation was found between test and retest (intercorrelation coefficient .908); the standard error of measurement was 6.7, and the minimal detectable change was 18.5. The Danish version of the ATRS showed moderately strong criterion validity. For study and follow-up purposes, the ATRS seems reliable for comparisons of groups of patients. Its usability is limited for repeated assessment of individual patients. The development of analysis guidelines would be desirable.