Skip to main content
. Author manuscript; available in PMC: 2014 Jun 1.
Published in final edited form as: Ophthalmic Epidemiol. 2013 Oct 29;20(6):10.3109/09286586.2013.848457. doi: 10.3109/09286586.2013.848457

Table 1. General demographic characteristics of the study groups.

Study group ALSPAC SCORM REHS IDFC
Recruitment site UK Singapore Australia Israel
Cohort type Birth cohort School-based cohort Birth cohort Military recruitment
candidates
Sample size 4,401 1,959 1,266 888,277
Ethnicity§ White European
100%		 Chinese (75%)
Malay (17%)
Indian (7%)
Eurasian (<1%)
Other (1%)
White European = 85%
Chinese=5%
Indian = 4%
Other = 6%		 Israeli family origins,
within 2 generations:
Israeli 10%
Western 36%
Eastern 54%
Age (years)
Mean±SD and range		 15.4 ± 0.3
(range 14-17)		 13.05 ± 2.33
(range 7-20)		 20.05 ± 0.44
(range 20-22)		 17.3 ± 0.5
(range 16–22)
Sex (%male) 47.2 50.6% 52% NA*
Method of refractive
estimation		 Non-cycloplegic
autorefraction		 Cycloplegic
autorefraction		 Cycloplegic
autorefraction		 Spectacle focimetry or
subjective refraction
Refraction (D)
Mean±SD		 −0.40 ± 1.27 −2.15 ± 2.48 −0.13 ± 1.60 NA*
§

For the IDFC, the “region of family origin” was used to categorize subjects’ ethnicity: Western = European, American, or Oceanic, Eastern = Asian or African.

*

information not available for release.