Treatment acceptability as indexed by the number of drop outs
Acceptability as indexed by the number of drop outs in each intervention arm
Satisfaction with treatment effectiveness as measured by the Modified Treatment Satisfaction Scale
Perceived perceived symptom improvements as well as overall treatment satisfaction as measured by the Modified Treatment Satisfaction Scale (TSS). The TSS is a 7 item questionnaire with total scores ranging from 7 to 35, with higher scores indicating greater treatment satisfaction. In the present study, the TSS was adapted for insomnia to measure symptom improvement in key areas including insomnia, energy level, work productivity, coping, life enjoyment, hopefulness, self-esteem, and mood.
Changes in insomnia symptoms
Changes in insomnia symptoms as indicated by the Insomnia Severity Index-7 (ISI-7) total score from pre-intervention to the last follow-up time point after the end of the intervention. The ISI-7 is a 7 item questionnaire with total scores ranging from 0 to 28, with higher scores indicating more severe insomnia symptoms.
Changes in EEG-based sleep latency
Changes in EEG-based sleep onset latency from pre- to post-intervention.
Changes in EEG-based total sleep time
Changes in EEG-based total sleep time from pre- to post-intervention.
Changes in EEG-based slow wave sleep
Changes in the amount of slow wave sleep measured with the EEG headband from pre- to post-intervention.
Changes in EEG-based slow wave activity
Changes in the amount of slow wave activity (spectral power in the delta frequency range) from pre- to post-intervention.
Changes in EEG power spectra
Changes in global EEG power spectrum as measured by the EEG headband from pre- to post-intervention.
Changes in EEG-based slow wave morphometrics
Changes in the density, amplitude, rate of ascending/descending phases of sleep slow waves as measured by the EEG headband from pre- to post-intervention.
Changes in heart rate
Changes in heart rate measures including beats per minutes and heart rate variability from pre- to post-intervention.
Changes in subjective sleep quality
Changes in subjective sleep quality as rated by the subscales of the Leeds Sleep Evaluation Questionnaire (LSEQ): getting to sleep (GTS), quality of sleep (QOS), Awake following sleep (AFS), behaviour following wakening (BFW). The LSEQ is contains 10 items rated on a 10-cm line analogue scale. Scores for each item range from 0 to 10, with total scores ranging from 0-30 for the GTS and BFW subscales and from 0-20 for the QOS and AFS subscales. Higher scores indicate greater improvements in sleep. This will be measured from pre-intervention to the last follow-up time point after the end of the intervention.
Changes in subjective pre-sleep arousal
Changes in subjective pre-sleep arousal as rated on the Pre-Sleep Arousal Scale (PSAS) from pre- to post-intervention. The PSAS is a 16-item questionnaire with total scores ranging from 16 to 80, with higher scores indicating greater cognitive and somatic pre-sleep arousal.
Changes in unhelpful beliefs about sleep
Changes in unhelpful beliefs about sleep as rated on the Dysfunctional Beliefs About Sleep (DBAS) questionnaire from pre- to post-intervention. The DBAS is a 16-item with total scores ranging from 0 to 160 and higher scores indicating greater dysfunctional beliefs and unrealistic expectations about sleep.
Changes in subjective fatigue
Changes in subjective fatigue as measured by the Fatigue Severity Scale (FSS) total score from pre-intervention to the last follow-up time point after the end of the intervention. The FSS is a 7 items scale with total scores ranging from 9 to 63, higher scores indicating greater fatigue severity.
Changes in clinician-assessed depression symptoms assessed with the Hamilton Depression Rating Scale
Changes in depression symptoms as assessed by the total score of the Hamilton Depression Rating Scale (HDRS). The HDRS is comprised of 17 items with total scores ranging from 0 to 52, with higher scores indicating greater depressive severity. This will be measured from pre-intervention to the last follow-up time point after the end of the intervention. Secondary analyses will be done on the HDRS total score minus the sleep items to disentangle the effects of sleep-related depression symptoms from that of other depression symptoms.
Changes in self-reported depression symptoms rated on the Quick Inventory of Depressive Symptomatology (QIDS). The QIDS is a 16-item questionnaire with total scores ranging from 0 to 27, with higher scores indicating greater depressive severity.
Changes in depression symptoms severity as assessed by the total score of the self-report version of the Quick Inventory of Depressive Symptomatology (QIDS). This will be measured from pre-intervention to the last follow-up time point after the end of the intervention. Secondary analyses will be done on the QIDS total score minus the sleep items to disentangle the effects of sleep-related depression symptoms from that of other depression symptoms.
Changes in self-reported depression symptoms rated on the Depression, Anxiety and Stress Scale
Changes in depression symptoms severity as assessed by the depression subscale of the Depression, Anxiety and Stress Scale (DASS-21) from pre-intervention to the last follow-up time point after the end of the intervention. The DASS-Depression subscale contains 7 items with total scores ranging from 0 to 42, and higher scores indicating greater symptom severity.
Changes in self-reported anxiety symptoms rated on the Depression, Anxiety and Stress Scale
Changes in anxiety symptoms severity as assessed by the anxiety subscale of the Depression, Anxiety and Stress Scale (DASS-21) from pre-intervention to the last follow-up time point after the end of the intervention. DASS-Anxiety subscale contains 7 items with total scores ranging from 0 to 42, and higher scores indicating greater symptom severity.
Changes in self-reported stress symptoms rated on the Depression, Anxiety and Stress Scale
Changes in stress symptoms severity as assessed by the stress subscale of the Depression, Anxiety and Stress Scale (DASS-21) from pre-intervention to the last follow-up time point after the end of the intervention. DASS-Stress subscale contains 7 items with total scores ranging from 0 to 42, and higher scores indicating greater symptom severity.
Objective-subjective discrepancy in sleep latency
Differences score where subjective sleep onset latency (derived from the sleep diary) is subtracted from objective sleep onset latency (derived by the EEG headband) collected at baseline (pre-intervention).
EEG-Actigraphy discrepancy in sleep latency
Differences score where actigraphy-based sleep onset latency is subtracted from EEG-based sleep onset latency collected at baseline (pre-intervention).
Objective-subjective discrepancy in total sleep time
Differences score where subjective total sleep time (derived from the sleep diary) is subtracted from objective total sleep time (derived by the EEG headband) collected at baseline (pre-intervention).
EEG-Actigraphy discrepancy in total sleep time
Differences score where actigraphy-based total sleep time is subtracted from EEG-based total sleep time collected at baseline (pre-intervention).
Objective-subjective discrepancy in sleep efficiency
Differences score where subjective sleep efficiency (derived from the sleep diary) is subtracted from objective sleep efficiency (derived by the EEG headband) collected at baseline (pre-intervention).
EEG-Actigraphy discrepancy in sleep efficiency
Differences score where actigraphy-based sleep efficiency (derived from the sleep diary) is subtracted from EEG-based sleep efficiency (derived by the EEG headband) collected in the entire sample at baseline (pre-intervention).
Qualitative feedback
Main themes emerging from qualitative interviews on participant's experiences with the intervention.