Development and psychometric evaluation of a lifestyle adherence assessment scale for patients with dry eye syndrome

OBJECTIVES: To develop the lifestyle adherence assessment scale for patients with dry eye syndrome and conduct validity and reliability analyses. DESIGN: A cross-sectional and methodological scale validation design, following classical test theory. METHODS: The study was conducted in three stages. The initial stage focused on item generation and revision, which involved a comprehensive literature analysis and expert inquiries. Phase two involved the assessment and exploration of items. The third phase involved a cross-sectional survey to establish construct validity, content validity, internal consistency reliability, and exploratory factor analysis. A total of 422 samples that met the study criteria were included during the second and third stages (June 2024 to March 2025). RESULTS: The final scale contains 18 items across five dimensions: ophthalmic care standards, ocular strain regulation standards, seeking supports, tobacco and alcohol consumption regulations, and daily conduct guidelines. Twenty-three experts with professional experience participated in two rounds of expert consultations. Expert authority coefficients were 0.854 and 0.894 in two Delphi rounds, with 100% response and validity rates. Exploratory factor analysis extracted five factors accounting for 54.65% of the variance. Confirmatory factor analysis indicated good model fit (χ²/df = 3.580, CFI = 0.958, TLI = 0.947, SRMR = 0.072, RMSEA = 0.038). The scale-level and item-level content validity indices were both 1.000. Cronbach’s α was 0.894, and test-retest reliability was 0.931. CONCLUSION: The Lifestyle Adherence Assessment Scale for Dry Eye Patients has excellent reliability and validity, making it a suitable instrument for evaluating patients’ adherence to lifestyle modifications.