Cross-cultural Adaptation and Validation of the Exercise-Induced Leg Pain Questionnaire for English- and Greek-Speaking Individuals
AuthorKorakakis, V.; Malliaropoulos, N.; Baliotis, K.; Papadopoulou, S.; Padhiar, N.; Nauck, T.; Lohrer, H.
STUDY DESIGN: Clinical measurement. OBJECTIVES: To translate the German version of the Exercise-Induced Leg Pain Questionnaire (EILP-G) to Greek and English and evaluate the psychometric properties of the Greek version. BACKGROUND: The EILP-G was developed to evaluate the severity of symptoms and sports ability in individuals with exercise-induced leg pain (EILP). Translation of the questionnaire to other languages will provide a standard outcome measure across populations. METHODS: The EILP-G questionnaire was cross-culturally adapted to Greek and English, according to established guidelines. The validity and reliability of the Greek version were assessed in 40 patients with EILP, 40 patients with other lower extremity injuries, 40 track-and-field athletes with no history of EILP, and 40 young adults without pathology. Participants completed the questionnaire at baseline and again after 7 to 10 days. RESULTS: The expert committee and the participants considered the questionnaire to have good face and content validity. Concurrent validity as assessed using the Schepsis score was almost perfect (rho = 0.947, P<.001). Dimensionality analysis revealed a 1-factor solution, explaining 83.8% of the total variance. Known group validity was demonstrated by significant differences between patients compared with the asymptomatic groups (P<.001). The Greek version exhibited excellent test-retest reliability (intraclass correlation coefficient = 0.995 for the EILP group) and internal consistency (Cronbach alpha = .942 for the EILP group). Finally, no ceiling or floor effects were found, as none of the individuals with EILP scored the maximum or minimum possible values on the questionnaire. CONCLUSION: The Greek version, adapted from the original EILP-G, is a valid and reliable questionnaire, and its psychometric properties are comparable with the original version.