Lifetime cost-effectiveness of myopia control intervention for the children population.

Background: Myopia is a common eye condition and projected to affect half of the global population by 2050. Controlling its progression during childhood may prevent associated ocular diseases in later life. Certain interventions retard myopia progression but their long-term costs and consequences are not well understood. We evaluated the cost-effectiveness of myopia control via an optical approach using the Defocus Incorporated Multiple Segments (DIMS) lens over a lifetime. Methods: We constructed an individual-based, state-transition model to simulate 1) the development and progression of myopia in childhood with and without control and 2) the impact of myopia on the development of four sight-threatening complications in adulthood. We compared strategies of myopia control with 100% uptake vs. no myopia control from the societal perspective to determine whether myopia control is value for money. Results: With myopia control, the cumulative prevalence of high myopia was relatively reduced by 44.7% (5.9 vs. 10.7%) and severe visual impairment by 19.2% (2.2 vs. 2.7%) compared to no myopia control. The lifetime cost per quality-adjusted life year gained was 26 407 US dollars (USD) and is considered cost-effective compared to the threshold recommended by the World Health Organization (WHO) of one times annual per capita gross domestic product (48 359 USD). Probabilistic sensitivity analysis showed that myopia control had an 87% likelihood of being cost-effective at the WHO threshold. Conclusions: Myopia control is cost-effective when provided to all eligible children. Further investigation is required to determine if it is cost-effective for the government to subsidise myopia control in order to maximise access.

Screening for diabetic retinopathy with or without a copayment in a randomized controlled trial: influence of the inverse care law.

OBJECTIVE: To examine whether the inverse care law operates in a screening program for diabetic retinopathy (DR) based on fee for service in Hong Kong. DESIGN: Randomized controlled trial. PARTICIPANTS: All those with type 1 or 2 diabetes from 2 clinics were recruited. INTERVENTION: Diabetic retinopathy screening with a small copayment versus free access in a publicly funded family medicine service. MAIN OUTCOME MEASURES: Uptake of screening and severity of DR detected. Association between these outcome variables and independent variables were determined using multivariate logistic regression models and reported as odds ratios (ORs). RESULTS: After randomization, 1387 subjects in the free group and 1379 subjects in the pay group were eligible for screening, and 94.9% (1316/1387) and 92.6% (1277/1379), respectively, agreed to participate in the study. The offer of screening was accepted by 94.8% (1247/1316) in the free group and 91.2% (1164/1277) in the pay group, and the final uptake ratios were 88.5% (1165/1316) and 82.4% (1052/1277), respectively (Pearson chi = 19.74, P<0.001). Being in the pay group was associated with a lower uptake of screening than being in the free group (OR, 0.59; confidence interval [CI], 0.47-0.74) and a lower detection rate of DR (OR, 0.73; CI, 0.60-0.90) after adjustment for potential confounding factors. Subjects with higher socioeconomic status were more likely to attend screening and had a lower prevalence of DR detected. CONCLUSIONS: The inverse care law seems to operate in a preventive intervention when a relatively small copayment is applied. There is a case for making effective preventive services free of charge. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Relationship between goblet cell density and tear function tests.

AIM: The objective of this study was to find a relationship between goblet cell density (GCD) and other diagnostic tests of dry eye in a group of normal healthy Chinese subjects. The capability of using GCD as a tear function test was assessed. METHOD: A total of 42 optometry students with no contact lens wear history were recruited. Subjects were required to fill in a dry eye questionnaire. The non-invasive tear break-up time (NITBUT) of each subject was measured, followed by phenol red thread test (PRTT) and tear break-up time (TBUT) tests. Conjunctival epithelial cells from the inferior nasal bulbar conjunctiva were harvested by the impression cytology technique. The specimens collected were labelled and stained with PAS (Periodic Acid Schiff)-haematoxylin. The goblet cells and the conjunctival epithelial cells were counted under a light microscope of 100x magnification. Spearman's rho (rho) correlation test was used to analyse the relationship between GCD and the other tear function tests. RESULTS: With a probability level of 0.0051 (corrected for a cumulative familywise error rate of p = 0.05), GCD was found to have no correlation with NITBUT (rho = -0.193, p = 0.222), McMonnies Dry Eye Scores (MCDES) (rho = -0.052, p = 0.742), PRTT (rho = - 0.188, p = 0.234) and TBUT (rho = 0.246, p = 0.117). CONCLUSION: There was no correlation between GCD and MCDES, NITBUT, PRTT and TBUT. The GCD alone is not a useful diagnostic test for tear film instability in normal eyes although it is a good indicator in the diagnosis of ocular surface diseases.