Table 2

Median daily illuminance exposure, time spent and epochs under different photopic light conditions

Categories of illuminance level (lux)All participants
(median (IQR))
Myopes
(median (IQR))
Non-myopes
(median (IQR))
Illuminance exposure level (lux/day)
≥1000 (typically considered outdoors)3007 (2421–3688)2767 (2399–3571)3073 (2489–3695)
≥30005679 (4945–6745)5454 (4844–5994)5969 (5024–7073)
≥50008517 (7674–10218)8339 (7626–8776)8628 (7792–10 774)
≥10 00014 042 (12 275–15 622)14 183 (13 033–15 725)13 996 (12 228–15 556)
Time spent in different outdoor photopic light levels (min/day)
≥100059 (32–86)51 (26–82)60 (34–90)
≥300018 (8–33)16 (6–27)20 (8–34)
≥50007 (2–15)6 (2–13)7 (3–16)
≥10 0002 (0–4)1 (0–3)2 (1–4)*
Epoch (times/day)
≥100021 (12–32)19 (12–27)24 (12–36)
≥300011 (5–17)8 (5–12)12 (5–18)
≥50005 (2–11)4 (2–6)6 (2–11)
≥10 0001 (0–3)1 (0–2)2 (0–4)
  • *Represents statistical significance at the level of <0.05 between myopes and non-myopes.