[Utilization of Quality-of-life assessment Questionnaires for Intermittent Exotropia in China]

Abstract

Objective: To evaluate the reliability and validity of Chinese version of Quality-of-life assessment Questionnaires for Intermittent Exotropia (CIXTQ).

Methods: Cross-sectional study. The original English version of the IXTQ was translated into Chinese. The final Chinese version of the IXTQ (CIXTQ) consists of 3 parts: the 12-item child CIXTQ (for children ≥5 and<8 years old and ≥8 and<18 years old, respectively, to assess their health quality of life (HRQoL)), the 12-item proxy CIXTQ (for parents to assess children's HRQoL), and the 17-item parent CIXTQ (containing functional, psychosocial, and surgery subscales; for parents to assess their HRQoL). 175 IXT children and 151 control children along with one of their parents were recruited to answer the CIXTQ. Cronbach's α coefficient and split-half reliability were used to test the internal consistency reliability of the CIXTQ. Kappa coefficient was used to assess the test-retest reliability. Scale-level content validity index/average (S-CVI/Ave) was used to evaluate the content validity of the CIXTQ. Principal component analysis (PCA) was used to verify the construct validity of the parent CIXTQ. Comparison of different CIXTQ scores in IXT patients with controls was conducted by independent-samples t test to evaluate the discriminate validity of the CIXTQ.

Results: For all scales and subscales of the CIXTQ in different age groups, the Cronbach's α ranged from 0.804 to 0.963; the split-half reliability ranged from 0.658 to 0.963 and was higher than 0.7 except for the proxy CIXTQ for children aged ≥5 and<8 years old; the test-retest reliability ranged from 0.569 to 0.944. The S-CVI/Ave of the child, proxy and parent CIXTQ was 0.988, 0.988 and 0.966, respectively. Principal factors identified by PCA for the parent CIXTQ could be regrouped into the originally described 3 subscales which was functional, social psychology and surgery in different age groups. The mean scores of all the scales and subscales among IXT children and their parents (8.0±12.5-81.6 ±15.1) were significantly lower than these among control children and their parents (83.1±11.3-99.6±1.2) (t values range from -50.36 to -6.93, P<0.001).

Conclusions: The CIXTQ are useful tools to evaluate the influence of IXT on HRQoL among Chinese children and their parents. (Chin J Ophthalmol, 2016, 52: 596-603).