Validation of the Child Amblyopia Treatment Questionnaire (CAT-QoL)
Purpose: The Child Amblyopia Treatment Questionnaire (CAT-QoL) is a patient-reported outcome (PROM) measure designed to assess the impact of amblyopia treatment. The aim of this study was to formally assess the psychometric properties of the CAT-QoL instrument.
Methods: 342 participants were recruited in a UK multi-centre validation study. Quality of life data was collected through using the CAT-QoL and the PedsQLTM instruments. The psychometric properties of the CAT-QoL were examined in terms of acceptability, reliability, and validity.
Results: Both instruments demonstrated good reliability (CAT-QoL Cronbach’s α = 0.793; PedsQLTM α =0.872). The CAT-QoL was able to detect differences between amblyopia severity groups. Statistically significant differences between the amblyopia severity level and mean CAT-QoL scores were found (p = 0.018). No statistical significance was found between the level of amblyopia severity and the mean PedsQLTM score (p = 0.420).
Conclusion: The results suggest that the CAT-QoL instrument may be more sensitive in its ability to detect quality of life implications of amblyopia treatment compared to the PedsQLTM instrument. The CAT-QoL is a low burden, self-complete PROM for children undergoing amblyopia treatment. Psychometric evaluation of the instrument suggests it meets the requirements of reliability and validity required in a PROM.