Overview of (the timing of) the patient-reported outcome measures (PROMs)
| Measurement | Instrument (PROMM) | Timing (Baseline, week 6, 12, 20, 52) |
| Background characteristics | Study-specific sex, age, body length and weight, highest attained educational level, current work status, smoking status, alcohol consumption, duration of insomnia, sleep treatment history. | Baseline |
| Sleep–main outcome | Insomnia Severity Index (ISI)*37 | All time points |
| Sleep–other outcomes | Pittsburgh Sleep Quality Index (PSQI)* 50 items 1–4 and the number of nights per week in which the participant experienced sleep problems. | All time points |
| Global rate of change
51
Sleep problem compared with baseline. | Week 6, 12, 20 | |
| Consensus sleep diary,52 pen-and-paper version, prospectively for 1 week. | Baseline, week 6 and 20 | |
| Functional impairments due to sleep problem | Work and Social Adjustment Scale (WSAS)* 53 | All time points |
| Glasgow Sleep Impact Index (GSII)42 part 1, 2 and 3. | All time points | |
| Fatigue | Multidimensional Fatigue Inventory (MFI)*54 | Baseline, week 12 and 20 |
| Flinders Fatigue Scale (FFS)55 items 4 and 6. | Baseline, week 12 and 20 | |
| Emotional complaints | Hospital Anxiety and Depression Scale (HADS),* 56 validated Dutch version.57 | Baseline, week 12 and 20 |
| Side effects | Antidepressant Side-Effect Checklist (ASEC-21),* 58 Dutch translation.59† At baseline symptom rate only. At follow-up in relation to treatment and current dose. | Baseline, week 6 and 12/ in case of treatment discontinuation as soon as possible. |
| Bodyweight Self-reported in kg. | All time points | |
| Withdrawal | Discontinuation-Emergent Signs and Symptoms (DESS) checklist,60 Dutch translation.61† | Week 20/in case of treatment discontinuation in combination with the next planned questionnaire. |
| Treatment evaluation | Study-specific details of usage (dose, timing of taking tablets), adherence and (reasons for) missed tablets and treatment satisfaction. | Week 20/in case of treatment discontinuation in combination with the next planned questionnaire. |
| Additional measures to improve sleep +life events | Study-specific other measures to improve sleep used by the participant; retrospectively over the intervention period and over the period after the intervention, life-events affecting sleep. | Week 20 and week 52. |
*Recall period adapted to past 2 weeks.
†Adapted for self-administration in insomnia disorder patients. The item ‘sleep problem’ was in the ASEC-21 replaced by the items ‘difficulty waking up’, ‘sleepiness in the morning’, ‘sleepiness in the afternoon’, ‘vivid dreams/disturbed sleep’ and omitted from the DESS list and evaluated in a separate item.