Table 5 Trouble concentrating or thinking clearly at baseline, week 7 and week 14 by group. Mean score derived from the Columbia Scale according to response to the second question, "Over the last 3 days how much have you been bothered by trouble concentrating or thinking clearly? Possible answers and scoring: 1 = not at all, 2 = a little bit, 3 = moderately, 4 = quite a bit, 5 = extremely.

From: The effect of high correlated colour temperature office lighting on employee wellbeing and work performance