Greek adaptation and validation of the Patellofemoral Pain Syndrome Severity Scale

Abstract

The purpose of this study was to cross-culturally adapt and validate the Greek version of the Patellofemoral Pain Syndrome (PFPS) Severity Scale, a self-reported instrument used for patients with PFPS. Four bi-lingual translators were involved in the translation and cultural adaptation procedures. Eighty-seven patients with PFPS (51 women and 36 men) participated in the study. To establish test–retest reliability, the patients were asked to complete the PFPS Severity Scale twice at initial visit; before and after physiotherapy treatment. The Greek version of the Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS) was also administered once. Internal consistency of the translated instrument was measured using Cronbach α. An intraclass correlation coefficient was used to assess the test–retest reliability of the PFPS Severity Scale. Concurrent validity was measured by correlating the PFPS Severity Scale scores with the KOS-ADLS scores using Pearson’s correlation coefficient. The results showed that the Greek PFPS Severity Scale has good internal consistency (Cronbach α = 0.949), test–retest reliability (ICC = 0.946) and concurrent validity (r > 0.7). In conclusion, the Greek version of PFPS Severity Scale is a reliable and valid measure when administered to patients with PFPS.