Development of the Italian version of the High-Activity Arthroplasty Score (HAAS-I) following hip and knee total arthroplasty: Cross-cultural adaptation, reliability, validity and sensitivity to change

Background: The number of physically active individuals who develop knee and hip arthritis and who undergo arthroplasties of these joints ie ever increasing. It has become necessary to develop evaluation scales which address the specific issues raised by such individuals. The High Activity Arthroplasty Score is one such scales, originally developed in English. Methods: The HAAS-I was developed by means of forward-backward translation, a final review by an expert committee and a test of the pre-final version to establish its correspondence with the original English version. The psychometric testing included reliability by means of internal consistency (Cronbach's alpha) and test-retest reliability (intraclass correlation coefficients) and construct validity by Pearson's correlations with a pain intensity numerical rating scale (NRS), the Western Ontario and McMaster University index (WOMAC, for THA subjects), the Knee injury and Osteoarthritis Outcome Scale (KOOS; for TKA subjects) and the Short-Form 36 Health Survey (SF-36). Results: The questionnaire was administered to 67 subjects with THA and 61 with TKA and proved to be acceptable. The questionnaire showed good internal consistency (0.85 for THA and 0.91 for TKA) and a high level of test-retest reliability (ICC = 0.97 with 95% CI 0.95-0.98 for THA; ICC = 0.95 with 95% CI 0.92-0.98 for TKA). There was a moderate correlation between the HAAS-I and NRS (r = - 0.40), there was a high correlation between the HAAS-I and WOMAC (r = - 0.68) and there were moderate to high correlations between the HAAS-I and SF-36 subscales (r = 0.34 to 0.63) for THA. There was a moderate correlation between the HAAS-I and NRS (r = - 0.77); there was a high correlation between the HAAS-I and KOOS subscales (r = - 0.79 to r = - 0.91); and there were low correlations between the HAAS-I and SF-36 subscales (r = 0.01 to 0.29) for TKA. Conclusions: The HAAS-I was successfully translated into Italian and proved to have good psychometric properties that replicated the results of existing versions. Its use is recommended for clinical and research purposes.