Table 3.
Heritability (h2) estimates for the trait explored in this study.
| Trait | Model | h2 ± SE | p Value | p Value of Covariates | Variance Explained by Final Covariates |
|---|---|---|---|---|---|
| MEQ score | Unadjusted | 0.19 ± 0.10 | 0.0295 | ||
| Adjusted best model | 0.37 ± 0.11 | 0.0001 | Age (5.63 × 10−31) Sex (0.0464) |
0.1943 | |
| MSFsc, min past midnight | Unadjusted | 0.17 ± 0.09 | 0.0295 | ||
| Adjusted best model | 0.32 ± 0.10 | 0.0002 | Age (8.75 × 10−20) | 0.1258 | |
| Dissipation of sleep pressure (MEQ factor, scale points) | Unadjusted | 0.15 ± 0.10 | 0.0587 | ||
| Adjusted best model | 0.32 ± 0.10 | 0.0004 | Age (1.32 × 10−34) Sex (0.0001) |
0.2256 | |
| Build-up sleep pressure (MEQ factor, scale points) | Unadjusted | 0.26 ± 0.11 | 0.0046 | ||
| Adjusted best model | 0.28 ± 0.11 | 0.0025 | Sex (0.0362) | 0.0055 | |
| MEQ Question 19 score | Unadjusted | 0.17 ± 0.11 | 0.0498 | ||
| Adjusted best model | 0.28 ± 0.11 | 0.0043 | Age (4.34 × 10−14) | 0.0850 |
Abbreviations: SE = standard error; MEQ = morningness-eveningness questionnaire; MSFsc = mid-sleep time on free days corrected for sleep debt on work days. Unadjusted and adjusted models for each trait, as well as the significant covariates, are presented.