The amblyopia treatment index

Objective: To develop a questionnaire to assess the acceptability of amblyopia treatment and its effect on the child and family. Methods: A 20-item parental survey was developed and pilot tested on 64 subjects, aged 3 to 6 years, participating in the Amblyopia Treatment Study, a randomized trial comparing patching and atropine as treatments for moderate amblyopia. The survey was administered after 4 weeks of treatment. A descriptive item analysis and an internal consistency reliability analysis were performed. Results: Nineteen of the 20 items demonstrated adequate variability as evidenced by the frequency distributions for item responses. Only 4 (<1%) of 1280 possible item responses were missing, one each by 4 different respondents. Factor analysis identified 3 treatment-related factors - "adverse effects," "compliance," and "social stigma" - among 11 of the 20 items. The internal-consistency reliability α for the 5-item adverse effects subscale was 0.82, the 4-item compliance subscale α was 0.81, and the 2-item social stigma subscale α was 0.84. Conclusions: The Amblyopia Treatment Index appears to be a useful instrument for assessing the impact of amblyopia treatment in 3-to 6-year-old children.