Internet-Based Cognitive Behavioral Therapy and Physical Activity for Insomnia (INSOMNIAC)

For Phase 1 pilot RCT only: Recruitment rate will be assessed as the average rate of participant recruitment as participants per week throughout the pilot RCT.

Measurement tool: Study screening and enrolment log.

For Phase 1 pilot RCT only: Consent rate will be assessed as the proportion of eligible/recruited participants who consent to participate.

Measurement tool: Study screening and consent log.

For Phase 1 pilot RCT only: Intervention adherence will be assessed as the proportion of participants completing ≥3 modules (50% of intervention), the minimum number required for an expected change in insomnia outcomes.

Measurement tool: The number of completed modules indicated by study clinician.

For Phase 1 pilot RCT only: Data collection completion will be assessed as the proportion of randomised participants who provide complete outcome data at baseline, post-intervention, 6 months, and 12 months.

Measurement tool: the outcome assessment database.

For Phase 1 pilot RCT only: Retention will be assessed as the proportion of randomised participants who have not withdrawn and who complete the follow-up assessments at 6 and 12 months.

Measurement tool: The participant tracking and follow-up log.

For Phase 1 pilot RCT only: Intervention fidelity will be assessed as the percentage of planned intervention components delivered as intended.

Measurement tool: Study-specific intervention fidelity checklist completed by study clinicians and platform delivery records.

For Phase 1 pilot RCT only: Acceptability will be assessed using semi-structured interviews with participants randomised to the iCBT-I-PA condition who completed at least the baseline measures. Interviews will explore participants' experiences of the intervention and pilot RCT procedures, including acceptability of the intervention, randomisation, outcome assessments, follow-up schedule, and barriers and facilitators to engagement.

Measurement tool: Semi-structured interview topic. Themes identified using thematic analysis.

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Insomnia severity will be the primary outcome that the intervention will aim to change. Insomnia severity will be measured using the Insomnia Severity Index (ISI). The ISI comprises seven items, measuring the severity and impact of insomnia and the extent to which it interferes with the individual's daily life. The ISI is scored on a 5-point Likert scale (0="Not at all", 4="Very much"). A sum score represents overall insomnia severity, ranging from 0 to 28.

Measurement tool: The Insomnia Severity Index (ISI)

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Sleep will be measured using a sleep diary: the Swedish version of the Core Consensus Sleep Diary (S-CSD). The S-CSD is a diary completed daily in the morning to assess nightly variation in sleep quality based on subjective sleep patterns. The S-CSD will yield Sleep Onset Latency, Wake After Sleep Onset, Total Sleep Time, Time in Bed, Sleep Efficiency, number of awakenings, and subjective sleep quality.

Measurement tool: The Swedish version of the Core Consensus Sleep Diary

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Sleep will be measured using a device-based measure, the thigh-worn triaxial SENS Motion® accelerometer. The accelerometer will be worn continuously for 9 consecutive days. Sleep metrics captured will be total sleep time, sleep onset/offset, sleep efficiency, and number of awakenings.

Measurement tool: SENS Motion® accelerometer

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Physical activity will be measured using a physical activity diary. The physical activity diary will be completed over seven consecutive days. Physical activity metrics captured will be the types of physical activities, their duration (in minutes) and perceived exertion (the Borg Rating of Perceived Exertion scale; 6-20; 6=no exertion, 20=maximal exertion).

Measurement tool: Physical Activity Diary (PAD)

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Self-reported physical activity will be measured using a two-item questionnaire capturing the time (in minutes) spent weekly on daily-life physical activity and structured physical activity, respectively.

For daily-life physical activity, response options will be 0, <30, 30-60, 60-90, 90-120 and >120 minutes.

For structured physical activity, response options will be 0, <30, 30-60, 60-90, 90-150, 150-300 and >300 minutes.

Measurement tool: the Swedish National Board of Health and Welfare questions for physical activity

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Device-based physical activity will be measured using the thigh-worn triaxial SENS Motion® accelerometer. The accelerometer will be worn continuously for 9 consecutive days. Physical activity metrics captured will be accelerations, steps, and daily minutes of light, moderate and vigorous physical activity.

Measurement tool: SENS Motion® accelerometer

For Phase 1 pilot RCT and Phase 2 full-scale RCT: A sedentary behaviour diary will be completed over seven consecutive days along with the physical activity diary. Sedentary behaviour metrics captured will be the duration of sitting, frequency of breaks in sitting, and the most common type of breaks across pre-defined segments of the day (i.e., morning, late morning, lunch, afternoon, dinner, evening, night).

Measurement tool: Part of the Physical Activity Diary (PAD)

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Self-reported sedentary behaviour will be measured using a single-item questionnaire capturing regarding the weekly time (in hours) spent sitting during waking hours.

Response options will be Almost all day, 13-15, 10-12, 7-9, 4-6, 1-3 hours and Never.

Measurement tool: Swedish National Board of Health and Welfare questions for sedentary behaviour (SED-GIH)

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Device-based sedentary behaviour will be measured using the thigh-worn triaxial SENS Motion® accelerometer. The accelerometer will be worn continuously for 9 consecutive days. Sedentary behaviour metrics captured will be total minutes of waking hours spent sedentary (sitting or reclining below 1.5 METs) and daily breaks in sedentary time.

Measurement tool: SENS Motion® accelerometer

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Cognitive function will be measured using the British Columbia Cognitive Complaints Inventory (BC-CCI), a six-item scale of perceived cognitive difficulties underlying depression, including memory, attention and concentration. Example item: "Forgetfulness / Memory Problems". The items are scored from 0=Not at all to 3=Very much. The sum of the six item scores ranges from 0 to 18. Higher scores indicate more severe perceived cognitive difficulties.

Measurement tool: the British Columbia Cognitive Complaints Inventory (BC-CCI)

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Depression will be measured using the Montgomery-Åsberg Depression Rating Scale (MADRS-S), a nine-item self-report measure assessing the severity of depressive symptoms, with higher scores indicating greater symptom severity.

Example item: "Concentration difficulties". The items are scored from 0=Item-specific lowest/No symptom anchor to 6=Item-specific most severe anchor. The sum of the nine item scores ranges from 0 to 54. Higher scores indicate greater depressive symptom severity.

Measurement tool: the Montgomery-Åsberg Depression Rating Scale (MADRS-S)

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Anxiety will be measured using the Generalized Anxiety Disorder 7-item scale assessing the severity of generalized anxiety symptoms over the past two weeks. Example item: "Feeling nervous, anxious, or on edge". The response options will be from 0=Not at all to 3=Nearly every day. The sum of the seven item scores ranges from 0 to 21. Higher scores indicate greater severity/frequency of anxiety symptoms.

Measurement tool: the Generalized Anxiety Disorder scale (GAD-7)

For Phase 1 pilot RCT and Phase 2 full-scale RCT: Pain will be measured using the single-item Numerical Rating Scale for Pain (NRS-P), assessing pain severity and the extent to which pain interferes with daily functioning. The item is scored from 0=No pain to 10=Worst pain imaginable. A higher score indicates greater pain and interference.

Measurement tool: the Numerical Rating Scale for Pain (NRS-P)