- Correlations among sleep quality, daytime sleepiness, and insomnia (n = 218).
| Characteristics | PSQI total score | ESS score | ISI score |
|---|---|---|---|
| PSQI total score | |||
| Pearson Correlation | 1 | .329** | .654** |
| Sig. (2-tailed) | .000 | .000 | |
| ESS score | |||
| Pearson Correlation | .329** | 1 | .407** |
| Sig. (2-tailed) | .000 | .000 | |
| ISI score | |||
| Pearson Correlation | .654** | .407** | 1 |
| Sig. (2-tailed) | .000 | .000 | |
↵Notes: ** Correlation is significant at p<.001, ESS-Epworth Sleepiness Scale; ISI-Insomnia Severity Scale; PSQI-Pittsburgh Sleep Quality Index