Exploratory and Confirmatory Factor Analyses for Testing Validity and Reliability of the Malay Language Questionnaire for Urinary Incontinence Diagnosis (QUID)

This study examines the construct validity and reliability of the Malay language questionnaire for urinary incontinence diagnosis (QUID) in women. Study Design: Random sampling design was used in this cross-sectional survey. Materials and Methods: The Americanized English language questionnaire was translated to the Malay language and distributed to community-dwelling Malaysian women living in various locations in Selangor. The construct validity was tested using exploratory factor analysis (EFA) followed by confirmatory factor analysis (CFA). The reliability was determined using Cronbach’s α. Results: A total of 111 women completed the Malay language QUID in this pilot study. The Keiser-Meyer-Olkin (KMO) measure of sampling adequacy of 0.675 and Bartlett’s test of sphericity (χ2 = 284.633, df = 15, p = 0.001) indicated that the EFA was possible. The total variance and the scree plot identified two factors above the initial eigenvalue of 1 while a third factor was just below it (0.758). The CFA output showed a recursive model with the solution being not admissible because two unobserved and exogenous variables had negative variance estimates. The following values of absolute fit indices showed an acceptable level of fit: 1) Chi-square test with χ2 = 4.997, df = 5, p = 0.416, indicated a smaller difference between the expected and observed covariance matrices; 2) GFI = 0.986, AGFI = 0.939, RMR = 0.021 and CMIN/DF = 1.0 indicated acceptable level of fit; 3) The baseline comparison values of NFI = 0.983 and CFI = 1.0 also indicated a good fit to the data; 4) RMSEA = 0.000 was considered a perfect fit indicating that the hypothesized model was a good fit to the observed data. Under the hypothesis of “close fit”, the probability of getting a sample RMSEA as large as 0.000 was 0.567. The Cronbach’s α coefficient of 0.823 indicated good reliability. Conclusion: The Malay language QUID is a valid and reliable instrument for diagnosing female urinary incontinence in the Malaysian population.