Rationale and Methodology of The PopulatION HEalth and Eye Disease PRofile in Elderly Singaporeans Study [PIONEER]
Preeti Gupta1, Ryan Eyn Kidd Man1, Eva K Fenwick1,2, Amudha Aravindhan1, Alfred TL Gan1, Sahil Thakur1, Bao Lin Pauline Soh3, Joanne M Wood4, Alex A Black4, Angelique Chan2, David Ng2, Teoh Khim Hean5, Edwin Goh5, Chong Foong-Fong Mary6, Jenny Loo7, Ciaran Gerard Forde8, Charumathi Sabanayagam1,2, Ching-Yu Cheng1,2,9, Tien Yin Wong1,2,9, Ecosse L Lamoureux1,2,9,*
1Singapore Eye Research Institute and Singapore National Eye Centre, Singapore. 2Duke-NUS Medical School, Singapore. 3Singapore Institute of Technology, Health and Social Sciences, Singapore. 4Queensland University of Technology, Brisbane, Australia. 5National Dental Centre, Singapore. 6Saw Swee Hock School of Public Health, National University of Singapore, Singapore. 7National University Hospital, Singapore. 8Singapore Institute for Clinical Sciences, National University of Singapore, Singapore. 9Department of Ophthalmology, National University of Singapore, Singapore
To describe the rationale, design and methodology of a geographically-representative and population-based study investigating the epidemiology, impact, personal and economic burden of age-related eye diseases, declining visual and other sensory systems in Asians aged >60 years in Singapore.PIONEER (The PopulatION HEalth and Eye Disease PRofilE in Elderly Singaporeans Study) is currently a cross-sectional study targeting 3152 Chinese, Malay and Indian adults who are Singapore citizens or permanent residents aged 60 years and older living across Singapore. The study is intended to be longitudinal, with several waves of data planned to be collected in the future. The sampling frame consisted of 7000 names derived from age, gender and ethnicity-stratified random sampling of individuals >60 years. Selected individuals were invited via letters, home visits, and telephone calls for a clinical assessment at the Singapore Eye Research Institute. Individuals with limited mobility were examined in a custom-designed mobile eye clinic. Questionnaires were subsequently administered at participants’ homes by trained interviewers in their preferred language. A total of 3,299 participants (from East, West, North and South Singapore) were approached from December 2017 to November 2019. Of these, 953 (28.5%) were deemed ineligible. Out of 2,346 eligible participants, 904 (38.5%) refused, and 1,442 (61.5%) attended our clinical testing protocol, giving an initial response rate of 61.5%. Of these, 1,170 (81%) were cognitively able to complete the questionnaire assessment. The mean age±SD of our participants was 73.8±8.6 years; n=798 (55.3%) were female; and 828 (57.4%) were of Chinese ethnicity. The findings from this study will allow a deeper understanding of the risk factors and impact of aging in Asian populations, particularly in relation to the visual function and other functional system.
Gupta Preeti,Man Ryan Eyn Kidd,Fenwick Eva K, et al. Rationale and Methodology of The PopulatION HEalth and Eye Disease PRofile in Elderly Singaporeans Study [PIONEER][J]. Aging and disease,
2020, 11(6): 1444-1458.
Figure 1. PIONEER sampling strategy and target sample size.
Figure 2. PIONEER study protocol.
Figure 3. A custom-designed mobile eye clinic, equipped with all necessary equipments to undertake the study protocol for participants with limited mobility.
Figure 4. PIONEER battery of clinical and questionnaire assessments.
Mean ± SD or n (%)
Participants n = 1442
Non-participants n = 904
73.8 ± 8.6
77.6 ± 8.7
Table 1 Age, gender and ethnicity of participants (n=1442) vs. non-participants (n=904).
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