Test-Retest Reliability and Validity of the Chinese Version of the College of Optometrists in Vision Development Quality of Life Questionnaire

Abstract

Objective: To examine the test-retest reliability and validity of the College of Optometrists in Vision Development Quality of Life questionnaire (COVD-QOL) that had been translated and culturally adapted to the Mandarin Chinese language. Methods: In this cross-section study, the final Chinese version of COVD-QOL was established after translation, back-translation and cognitive interviews based on the Brislin translation model. A sample of 20-23 year-old subjects (118 participants) from Xiamen Medical College completed the Chinese version of COVD-QOL, only 80 subjects were retested after three weeks. All data were analyzed using item analysisi, Cronbach's α coeffcient, retest reliability and so on. Results: The correlation coefficient between each item score and total score ranged from 0.333 to 0.684 (P<0.01). The coefficient of internal consistency (Cronbach's α) was 0.791, the Chinese version of COVD-QOL had good retest reliability with a Pearson correlation coefficient of 0.750 (P=0.002). The content validity index was 0.985. The construct validity was not good, because six factors were extracted by exploratory factor analysis, which could explain 62.3% of the total variance, but the results cannot be analyzed by professional interpretation. Conclusions: The Chinese version of COVD-QOL demonstrates good test-retest reliability and content validity. This questionnaire is an appropriate tool to assess the changes in visual symptoms for these native Chinese language speakers. Key words: college of optometrists in vision development; quality of life questionnaire; COVD-QOL; reliability; validity