Adaptation and transcultural translation of the Rotator Cuff Quality of Life questionnaire into Spanish

Abstract

Background: The objective of this study was the transcultural adaptation of the Rotator Cuff Quality of Life questionnaire and the determination of the reliability and validity of the questionnaire in the Spanish population with rotator cuff disease. One of the translators was a physiotherapist, and the other was an English philologist.

Methods: The participants comprised 170 subjects with rotator cuff pathology. Test-retest reliability was established by the intraclass correlation coefficient. Internal consistency was established using the Cronbach α. Convergent validity was established by comparison with the Disabilities of the Arm, Shoulder and Hand questionnaire, Shoulder Pain and Disability Index, Spanish version of the Oxford Shoulder Score, and Spanish version of the Western Ontario Shoulder Instability index using the Spearman correlation coefficient. Estimation of the error in the measurements was calculated with the standard error of measurement. Assessment of reproducibility was performed with 30 minutes between the first and second administrations of the questionnaire.

Results: The Cronbach α was 0.99, showing high internal consistency. The intraclass correlation coefficient was 0.9 (95% confidence interval, 0.99-0.99; P < .001), indicating high test-retest reliability. The Spearman correlation coefficient showed a good relationship in all cases: Disabilities of the Arm, Shoulder and Hand, ρ = 0.9 (P < .001); Oxford Shoulder Score, ρ = 0.7 (P < .001); Shoulder Pain and Disability Index, ρ = 0.8 (P < .001); and Western Ontario Shoulder Instability index, ρ = 0.8 (P < .001). The standard error of measurement indicated little variability in the measurements (2.7%).

Conclusions: The Spanish version of the Rotator Cuff Quality of Life questionnaire is a valid and reliable instrument for the subjective evaluation of patients with a diagnosis of rotator cuff pathology in the Spanish population.

Keywords: RC-QOL; Spanish; quality of life; questionnaire; reliability; rotator cuff injuries; validity.