Cross-cultural translation and validation of the Spanish version of the patellofemoral pain and osteoarthritis subscale of the KOOS (KOOS-PF)

Abstract

Objective The aim of this study was to translate to Spanish the patellofemoral pain and osteoarthritis subscale of the knee injury and osteoarthritis outcome score (KOOS-PF) and validate this Spanish version of a disease-specific patient-reported outcome measure (PROM) for patellofemoral pain. Results The KOOS-PF was translated to Spanish and sixty patients with patellofemoral pain and/or osteoarthritis accepted to complete the questionnaire. 1-week later 58 patients answered the questions again for the test–retest reliability validation and finally 55 patients completed 1-month later for the responsiveness assessment. The Spanish version showed very good internal consistency (Cronbach’s alpha: 0.93) and test–retest reliability (intraclass correlation coefficient: 0.82). Responsiveness was confirmed, showing a strong correlation with the global rating of change (GROC) score (r 0.64). The minimal detectable change was 11.1 points, the minimal important change was 17.2 points, and there were no floor or ceiling effects for the score.

Clinical value of questionnaires & physical tests for patellofemoral pain: Validity, reliability and predictive capacity

“…Overall, all questionnaires showed a strong correlation with each other ( r >0.78), with KOOS-PF values being the highest. The correlation of KOOS-PF with KPS showed values even higher than those obtained in other studies [ 30 , 41 ]. Despite the good results, KOOS-PF showed significant differences between its two measurement moments.…”

“…Evaluations were conducted between 01 December 2022 and 28 February 2023. Each subject was assessed in two sessions, 7–10 days apart; enough time to avoid recall of their answers, but not too long after to avoid clinical changes in PFP [ 29 , 41 ], since the purpose of the study was not to assess the effect of an intervention.…”

Knee Injury and Osteoarthritis Outcome Score Patellofemoral Questionnaire: Psychometric Properties among Females of Kingdom of Saudi Arabia

“…In this study, Ar-KOOS-PF-F demonstrates a moderate degree of association with VAS (r = −0.783; p = 0.023), which is a good association when compared to our validation of males [20] and (r = 0.71) of the Spanish KOOS-PF reported with the Spanish Kujala score [45]. These findings were very similar to the correlation between Arabic-version KOOS-SF and VAS (pain-0.71, symptoms-0.59 and QOL-0.64) [41].…”

“…The average ICC (0.96) of Ar-KOOS-PF-F shows an excellent test-retest reliability and is above the original KOOS-PF (ICC = 0.86) [19] and Spanish KOOS-PF (ICC = 0.82) [45]. The ICC of Arabic-Version Long KOOS was 0.959 and higher for the symptoms (0.94), corresponding to PF1, pain (0.93) corresponding to PF2-10 and QOL (0.93) corresponding to PF11 of Arabic-version KOOS-PF [41].…”