Rationale and methodology for a population-based study of eye diseases in Malay people: The Singapore Malay eye study (SiMES)

Purpose: Although there are approximately 200 million people of Malay ethnicity living in Asia, the burden and risk factors of blinding eye diseases in this ethnic group are unknown. This study summarizes the rationale and study design of a population-based study of eye diseases among adult Malays in Singapore. Methods: A population-based cross-sectional study of Malays was designed in Singapore. The sampling frame consisted of all Malays aged 40-79 living in designated study areas in southwestern Singapore. From a list of 16,069 names provided by the Ministry of Home Affairs, age-stratified random sampling was used to select 5,600 names (1,400 people from each decade of 40-49, 50-59, 60-69, and 70-79 years). The target sample size for this study was 3,150 persons. Selected individuals were invited to a centralized clinic by letters, telephone calls, and home visits. Participants underwent standardized interview and assessment of blood pressure, anthropometry, presenting and best-corrected visual acuity, subjective refraction, ocular biometry, Goldmann tonometry, slit-lamp biomicroscopy, optic disc imaging, digital lens, and retinal photography. Blood and urine samples were collected for biochemical analyses and further stored for future studies. Selected participants also had gonioscopic examination, visual fields test, and assessment of ankle and brachial blood pressure to detect presence of peripheral vascular disease. Conclusions: This study provides population-based data on the prevalence of and risk factors for age-related eye diseases in people of Malay ethnicity in Singapore. Data from this study allow further understanding of the etiology and impact of eye diseases in this ethnic group.