Purpose: To develop and validate a new parental questionnaire addressing symptoms and health-related quality of life (HRQL) in childhood nasolacrimal duct obstruction (NLDO).
Design: Cross-sectional study.
Participants: Children ages 6 to younger than 48 months with and without clinical signs of NLDO.
Methods: A new questionnaire was developed using semistructured interviews with parents of children with NLDO and through discussions with expert clinicians. Questionnaires were completed by parents of children with and without NLDO. Cronbach's alpha was calculated as a measure of internal-consistency reliability. Factor analysis was used to evaluate a priori subscales: symptoms and HRQL. Discriminant construct validity was assessed by comparing questionnaire scores between children with and without NLDO and between affected and unaffected eyes of children with unilateral NLDO. Instrument responsiveness was determined by comparing presurgical and postsurgical intervention scores in a subset of NLDO patients who underwent surgical treatment.
Main outcome measure: The NLDO questionnaire score.
Results: Eighty-seven children were enrolled, 56 with and 31 without NLDO. All but 2 questions on the questionnaire showed a good distribution of responses, a high correlation with the rest of the questionnaire, and excellent discrimination between patients with and without NLDO. Cronbach's alpha values were good for the overall questionnaire (0.95), and for 2 predetermined subscales: symptoms (0.95) and HRQL (0.85). On a 0 to 4 scale, NLDO patients had worse scores compared with non-NLDO patients for both symptoms (mean difference, 2.1; 95% confidence interval [CI], 1.9-2.3) and HRQL (mean difference, 1.2; 95% CI, 0.9-1.5) subscales. The NLDO patients had worse scores before intervention compared with after intervention for both the symptoms (mean difference, 2.2; 95% CI, 1.6-2.9) and HRQL (mean difference, 1.4; 95% CI, 0.8-2.1) subscales. Finally, NLDO patients had worse symptom scores for affected eyes compared with unaffected eyes (mean difference, 2.3; 95% CI, 1.9-2.6).
Conclusions: This novel NLDO questionnaire is useful in quantifying parental perception of symptoms and HRQL in childhood NLDO. The questionnaire may have a role in future clinical studies of NLDO.