Table 1 Eligibility criteria for participants
| Inclusion criteria | |
| Age ≥ 18 | |
| Regularly (> 6 times per month) working outside the hours of 6 a.m. to 10 p.m. | |
| Subjective sleep issues diagnosed in the screening process | |
| Exclusion criteria | |
| Acute suicidality as measured by the respective item in the BDI-II at T0 | |
| Ongoing alcohol or drug abuse | |
| No access to required technology (PC, smartphone, tablet)a |