Figure 6.

(A) Psychomotor vigilance testing (PVT) as reaction time in male (n = 8) and female (n = 17) participants at baseline, before the first shift regardless of treatment arm. Reaction times were significantly faster in males than females at baseline (P = 0.006). (B) PVT tests before and after placebo shifts and (C) PVT before and after melatonin shifts. Female participants’ data points are shown in green and male participants’ in orange. Reaction times were faster in males than females during all shifts. Reaction times were significantly higher after shifts (P = 0.0007) in both males and females than before. Box and whisker plots show median, interquartile, and full range with individual raw data points overlaid.