Assessing the Impact of Digital Cognitive Behavioural Therapy for Insomnia on Depression Symptoms and Processes in Young Adults.

INTERVENTION: Digital Cognitive Behavioural Therapy for Insomnia (Digital CBTI). Rationale: Digital CBTI (i.e., CBTI delivered in a digital format) is a well validated treatment for Insomnia. CBTI programs are known to effectively reduce symptoms of depression without directly targeting non‐sleep symptoms. However, the mechanisms which underlie the association between improvement in insomnia and improvements in depression are not well understood. Many candidate mechanisms have been proposed (e.g., cognitive biases), yet, there is a lack of research which investigates these possible mechanisms, and data from treatment studies is greatly needed to investigate the causal role of these mechanisms in the association between insomnia and depression. Type: Non‐drug, online, interactive Setting/location: Online, any location in Australia Duration: 5 X20 minute online sessions, delivered over 5 consecutive weeks Protocol: This program is based on CBTI, the recommended treatment for insomnia (e.g. Qaseem et al., 2016, Ann Intern Med, DOI: 10.7326/M15‐2175). It is based on a digitised version of a brief CBTI protocol described in a scientific article in the Australian Journal of General Practice (Sweetman et al., 2021, AJGP, doi: 10.31128/AJGP‐04‐20‐5391). Content: Each session will be administered online (computer or mobile phone). Each session will contain videos, text, and images. Participants will be asked to enter text‐based, numerical (e.g. minutes of sleep duration) and multiple‐choice data throughout the program. Participants will receive tailored therapy recommendations (e.g., prescribed time in bed) during each weekly session, determined by an in‐built algorithm and participants' entered data (see Sweetman et al., 2021, Aus J General CONDITION: Depression; ; Depression Mental Health ‐ Depression Mental Health ‐ Other mental health disorders PRIMARY OUTCOME: Between‐group change in self‐reported depression symptoms on the Patient Health Questionnaire (PHQ‐9). [PHQ‐9 Between‐group change in PHQ‐9 scores from baseline to 8‐week follow‐up post‐randomisation (primary timepoint). ; ; Change in PHQ‐9 scores from baseline to 16‐week and 24‐week follow‐up. ] SECONDARY OUTCOME: Between‐group change in attentional control on a computerised version of the Anti‐saccade Task (AS Task) [AS Task Between‐group change on the AS Task from baseline to 8‐week follow‐up post‐randomisation. ; ; Change on the AS Task from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in emotion recognition on a computerised version of the Penn Emotion Recognition‐40 test. [Penn Emotion Recognition‐40 test Between‐group change in the Penn Emotion Recognition‐40 test from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in the Penn Emotion Recognition‐40 test from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in executive functioning on a computerised version of the Wisconsin Card Sorting Task (WCST) [Wisconsin Card Sorting Task (WCST) Between‐group change on the WCST from baseline to 8‐week follow‐up post‐randomisation. ; ; Change on the WCST from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported anxiety symptoms on the Generalised Anxiety Disorder Questionnaire‐7 (GAD‐7). [GAD‐7 Between‐group change in GAD‐7 scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in GAD‐7 scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported approach‐related behaviour on the Behavioural Inhibition System and Behavioural Activation System Scales (BIS/BAS) [BAS Between‐group change in BAS scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in BAS scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported emotion expressivity on the Emotional Expressivity Scale (EES). [EES Between‐group change in EES scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in EES scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported emotion reactivity on the Perth Emotional Reactivity Scale Short‐Form (PERS‐S). [PER‐S Between‐group change in PERS‐S scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in PERS‐S scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported emotion regulation ability on the Perth Emotion Regulation Competency Inventory (PERCI) [PERCI Between‐group change in PERCI scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in PERCI scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported friendship, isolation, negative and positive attitudes to solitude on the Perth A‐Loneness Scale (PALs). [PALs Between‐group change in PALs scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in PALs scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported insomnia severity.[Change in insomnia symptoms on the Insomnia Severity Inde X(ISI) Between‐group change in ISI scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in ISI from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported repetitive negative thinking on the Persistent and Intrusive Negative Thoughts Scale (PINTS). [PINTS Between‐group change in PINTS scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in PINTS scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in self‐reported withdrawal‐related behaviour on the Behavioural Inhibition System and Behavioural Activation System Scales (BIS/BAS)[BIS Between‐group change in BIS scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in BIS scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ; ] Between‐group change in sleep‐related and depression‐related attention bias on a computerised Dual‐Probe Attention‐Bias task. [Dual‐Probe Attention‐Bias Task. Between‐group change on the Dual‐Probe Attention‐Bias Task from baseline to 8‐week follow‐up post‐randomisation. ; ; Change on the Dual‐Probe Attention‐Bias Task from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Between‐group change in sleep‐related and depression‐related interpretation bias on an Ambiguous Scenarios Test. [Ambiguous Scenarios Test. Between‐group change on an Ambiguous Scenarios Test from baseline to 8‐week follow‐up post‐randomisation. ; ; Change on an Ambiguous Scenarios Test from baseline to 16‐week and 24‐week follow‐up. post‐randomisation ] Between‐group change in working memory on a computerised version of the Digit Span Backwards Task (DSB) [Digit Span Backwards Task Between‐group change on the DSB from baseline to 8‐week follow‐up post‐randomisation. ; ; Change on the DSB from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ] Change in daytime sleepiness.[Change in symptoms of daytime sleepiness on the Epworth Sleepiness Scale (ESS), Between‐group change in ESS from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in ESS from baseline to 16‐week and 24‐week follow‐up post‐randomisation.] Change in Dysfunctional Beliefs about Sleep[Change in beliefs about sleep on the Dysfunctional Beliefs and Attitudes about Sleep Scale (DBAS‐16) Between‐group change in DBAS‐16 scores from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in DBAS‐16 scores from baseline to 16‐week and 24‐week follow‐up post‐randomisation.] Change in fatigue. [Change in symptoms of daytime fatigue on the Flinders Fatigue Scale (FFS) Between‐group change FFS from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in FFS from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ; ] Change in self‐reported sleep.[Change in self‐reported sleep metrics (e.g., Total Sleep Time, Sleep Onset Latency) as indicated by a Sleep Diary. Between‐group change in Sleep Diary metrics from baseline to 8‐week follow‐up post‐randomisation. ; ; Change in Sleep Diary metrics from baseline to 16‐week and 24‐week follow‐up post‐randomisation. ; ] INCLUSION CRITERIA: Young adults aged 18 – 24 years. PHQ‐9 score of 10 or above (i.e., moderate depression symptoms) Reliable access to computer, tablet or smartphone, with internet access Basic English language comprehension as required for digital CBTI program