1.Psychometric Properties of the Malay Language Version of Knee Injury and Osteoarthritis Outcome Score (KOOS) Questionnaire among Knee Osteoarthritis Patients: A Confirmatory Factor Analysis
Zulkifli MM ; MMed Fam Med ; Kadir AA ; MMed Fam Med ; Elias A
Malaysian Orthopaedic Journal 2017;11(2):7-14
Introduction: This study aimed to cross-culturally adapt a
Malay version of Knee Injury and Osteoarthritis Outcome
Score (KOOS) and to evaluate its psychometric properties in
patients with knee osteoarthritis (OA).
Materials and Methods: The English version KOOS was
translated into a Malay version using forward and backward
translation process, followed by face validity and content
validity. Two hundred and twenty-six knee OA patients
attending the Outpatient and Orthopaedic Clinics, Universiti
Sains Malaysia Hospital, completed the Malay version
KOOS. Construct validity using confirmatory factor analysis
and internal reliability assessment were performed.
Results: The results showed that the original five-factor
model with 42 items failed to achieve acceptable values of
the goodness of fit indices, indicating poor model fit. A new
five-factor model of 26 items demonstrated acceptable level
of goodness of fit (comparative fit index= 0.929, incremental
fit index= 0.930, Tucker Lewis fit index= 0.920, root mean
square error of approximation= 0.073 and Chisquared/degree
of freedom= 2.183) indices to signify a
model fit. The Cronbach’s alpha value for the new model
ranged from 0.776 to 0.946. The composite reliability values
of each construct ranged between 0.819 and 0.921,
indicating satisfactory to high level of convergent validity.
Conclusion: The five-factor model with 26 items in the
Malay version of KOOS questionnaire demonstrated a good
degree of goodness of fit and was found to be valid, reliable
and simple as an assessment tool for symptoms, pain activity of daily living, sports and recreational activity and
quality of life for Malaysian adults suffering from knee
osteoarthritis.