Brief Cognitive Behavioural Therapy for Insomnia Versus Sleep Hygiene for Sleep Difficulties in Early Pregnancy

The STICSA is a 21-item self-report scale that assesses cognitive and somatic components of anxiety. The STICSA is comprised of a state scale that measures individuals' current anxiety symptoms, and a trait scale that assesses one's proneness to anxiety, more generally. In the present study, only the trait scale of the STICSA will be used. Items are scored on a 4-point scale ranging from 1 ('not at all') to 4 ('very much so'). The STICSA has demonstrated excellent validity and reliability. A cut-off score of 43 or higher on the STICSA has been suggested for detecting a probable anxiety disorder. The STICSA has been validated for use in clinical samples of adults with anxiety disorders, although not explicitly in perinatal samples.

The EPDS is a 10-item self-report measure that assesses symptoms of depression during the perinatal period. Items are scored on a 4-point scale ranging from 0 to 3, with higher scores reflecting greater depressive symptomatology. The EPDS has demonstrated good sensitivity and specificity for a diagnosis of Major Depressive Disorder (MDD). Cut-off scores of 15 and 13 or higher have been suggested for detecting a probable diagnosis of MDD during pregnancy and the postpartum period, respectively.

The DERS is a 36-item self-report scale designed to assess difficulties with emotion regulation. The DERS contains six subscales that measure: non-acceptance goals, impulse, awareness, strategies, and clarity. Items are rated on a 5-point Likert scale, ranging from 1 (almost never, 0-10%) to 5 (almost always, 91-100%), with higher scores reflecting greater difficulties regulating emotions. The DERS has demonstrated good internal consistency (α=0.86) and test-retest reliability (0.74).

The GAD-7 is a 7-item self-report measure that assesses anxiety symptom severity over a previous two-week period. Items are measured on a 4-point scale ranging from 0 ('not at all') to 3 ('nearly every day'). A cut-off score of 10 or higher with sensitivity of 89% and specificity of 82% has been suggested for detecting a probable diagnosis of Generalized Anxiety Disorder. The GAD-7 has also been validated for use in perinatal samples.

The PSWQ is a 16-item self-report measure that assesses the tendency to worry. Items are scored on a 5-point scale ranging from 1 ('not typical at all') to 5 ('very typical'), with higher scores reflecting greater pathological worry. A cut-off score of 62 or higher has been suggested for determining a probable GAD diagnosis. The PSWQ has demonstrated excellent internal consistency and validity across various populations and has been validated for use in perinatal samples.

The PSAS is a 16-item self-report measure that assesses one's state of arousal as they fall asleep. The measure consists of two subscales, one intended to measure cognitive arousal and the other somatic arousal. Participants are asked to describe how intensely they generally experience each cognitive and somatic symptom as they attempt to fall asleep in their own bedroom. Items are scored on a 5-point scale from 1 ('not at all') to 5 ('extremely), with subscale scores ranging from 8-40. Higher scores represent greater pre-sleep arousal.

The PROMIS Anxiety Short-Form is an 8-item self-report measure designed to assess anxious apprehension and hyperarousal. Participants rated the frequency of their symptoms on a 5-point scale ranging from 1 ('not at all') to 5 ('very much'), with higher scores representing greater anxiety. The measure was adapted to assess the frequency of symptoms in the past day rather than the past 7 days as used previously. The PROMIS Anxiety Short-Form has demonstrated good internal consistency (Cronbach's α = .93) and good psychometric properties.

The PROMIS Depression Short-Form is an 8-item self-report measure that assesses negative mood and negative views of self. Participants rated the frequency of their symptoms on a 5-point scale ranging from 1 ('not at all') to 5 ('very much'), with higher scores representing greater depression. The measure was adapted to assess the frequency of symptoms in the past day rather than the past 7 days as used previously. The PROMIS Depression Short-Form has demonstrated good internal consistency (Cronbach's α = .95) and good psychometric properties.

The CSD was developed by a committee of experts with the aim of proposing a new improved and standardized sleep diary. This sleep diary will be filled out in the morning and includes questions such as (a) what time the participant went to bed, (b) what time they intended to sleep, (c) how long they were awake during the night, (d) what time they woke for the final time, (e) what time they got out of bed, and (f) how much sleep the participant got that night. From this data, we will derive time in bed, sleep onset latency, wakefulness after sleep onset, total sleep time, and sleep efficiency.

PSG recordings will be obtained using a device recording system that is self-applied at home. Portable PSG devices are primarily used for the screening of obstructive sleep apnea and growing research supports their use to evaluate sleep architecture and sleep quality. Standard recommendations suggest using PSG as a quantitative dependent measure in sleep research. Following these recommendations, PSG will be used for 2 nights to identify and quantify sleep-related breathing disturbances, periodic limb movements during sleep, and derive sleep measures (e.g., sleep onset latency, wakefulness after sleep onset, number of awakenings, total sleep time, terminal wakefulness, sleep efficiency).

Actigraphy watches are wrist-worn and battery-operated activity monitors that look similar to a small wristwatch. These devices are used to measure sleep and activity patterns and are typically used as an adjunctive measure in the diagnosis and treatment of insomnia to improve the reliability of self-report estimates of sleep. In this study, data collected from the actigraphy watches will be used to calculate objective measures of sleep such as sleep efficiency, total sleep time, time in bed, sleep onset latency, number of awakenings during the night, time awake after sleep onset, and terminal wakefulness.