Table 2 Subjective sleep parameters during a randomized, double-blind, placebo-controlled crossover study of shift work nurses: results at baseline and after 1 night melatonin or placebo treatment (N = 86)
| Â | Â | Mean | SD | P(vs.baselinea) | P(vs.placeboa) | Fb | Pb |
|---|---|---|---|---|---|---|---|
Sleep onset latency | Melatonin | 21.5 | 17.7 | < 0.05 | < 0.05 | 6.3 | 0.01 |
| Â | Placebo | 49.7 | 30.3 | < 0.05 | Â | Â | Â |
| Â | Baseline | 37.5 | 41.3 | Â | Â | Â | Â |
Total sleep time | Melatonin | 392.1 | 52.4 | > 0.05 | > 0.05 | 0.49 | NS |
| Â | Placebo | 372 | 49.4 | > 0.05 | Â | Â | Â |
| Â | Baseline | 450.5 | 82.3 | Â | Â | Â | Â |
Number of awakenings | Melatonin | 5.1 | 1.9 | > 0.05 | > 0.05 | 0.64 | NS |
| Â | Placebo | 5.1 | 1.9 | > 0.05 | Â | Â | Â |
| Â | Baseline | 5.2 | 2.1 | Â | Â | Â | Â |