Sleep Difficulties After Loss: Exploring the Beneficial Effect of Brief Behavioral Therapy for Insomnia in a Sample of Bereaved Individuals

The ISI measures the severity of insomnia symptoms and the associated impact on daytime functioning and distress. The questionnaire consists of 7 questions the sum of which makes up a total score. The ISI has a range of 0-28, with higher scores indicate worse insomnia severity.

Changes in sleep quality will be assessed using the Pittsburgh Sleep Quality Index (PSQI), with scores ranging from a minimum of 0, indicating no difficulty, to a maximum of 21, indicating severe difficulties in all areas related to sleep.

The Consensus Sleep Diary measures self-reported sleep providing various sleep parameters such as sleep duration, sleep onset latency (SOL), time in bed (TIB), total sleep time (TST), wake after sleep onset (WASO) and sleep efficiency (SE).

The Morningness-Eveningness Questionnaire-reduced (MEQr) will be used to assess circadian rhythm preferences (chronotype). This 5-item questionnaire evaluates sleep-wake patterns, preferred activity times, and subjective alertness at different times of the day. Scores categorize individuals as morning types, evening types, or intermediate types, with higher scores indicating a preference for morningness and lower scores indicating a preference for eveningness.

The A-PGDs is a validated self-report instrument that will be used to measure symptoms of prolonged grief disorder, including yearning, emotional pain, difficulty moving on, and functional impairment. Items are rated on a Likert scale, and higher scores reflect more severe grief symptoms.

The CESD-10 is a short self-report questionnaire that will be used to measure the frequency of depressive symptoms over the past week. Scores range from 0 to 30, with higher scores indicating greater depressive symptom severity.

The GAD-7 will be used to measure generalized anxiety symptoms. It consists of 7 items rated on a 4-point Likert scale. Total scores range from 0 to 21, with higher scores reflecting greater anxiety severity.

The PCL-5 - Short Form is an abbreviated version of the PTSD Checklist that assesses core symptoms of post-traumatic stress disorder based on DSM-5 criteria. Items are rated on a Likert scale, with higher scores indicating greater PTSD symptom severity.

MyGrief is a self-report questionnaire designed to evaluate grief-related symptoms and coping, specifically in relation to bereavement. It includes 33 items on emotional, cognitive, and functional aspects of grief, with higher scores reflecting greater grief-related difficulties.

The Perceived Stress Scale (PSS) will be used to measure the perception of stress. This 10-item questionnaire assesses how unpredictable, uncontrollable, and overloaded respondents find their lives. Higher scores indicate higher levels of perceived stress.

The Short-Form (12) Health Survey (SF-12) will be used to assess health-related quality of life. This questionnaire comprises 12 items that evaluate eight domains of health: physical functioning, role limitations due to physical health problems, bodily pain, general health perceptions, vitality (energy/fatigue), social functioning, role limitations due to emotional problems, and mental health (psychological distress and well-being). Scores from these domains are combined to yield two summary measures: the Physical Component Summary (PCS) and the Mental Component Summary (MCS). Higher scores indicate better health-related quality of life across the evaluated domains.

The WHO-5 is a brief measure of subjective psychological well-being, consisting of 5 positively worded items. Higher scores indicate better well-being.

The Neuroticism domain of the NEO-PI-R assesses the tendency to experience negative emotions such as anxiety, anger, and depression. It is a self-report measure derived from the full NEO-PI-R personality inventory. Higher scores indicate greater neuroticism.

The ECR-S is a 12-item self-report questionnaire that measures adult attachment patterns, specifically attachment anxiety and attachment avoidance in close relationships. Higher scores reflect higher levels of attachment insecurity.

Treatment expectancy and rationale credibility will be measured with the Expectancy/Credibility Questionnaire (CEQ). Scores for each question range from 1 to 9 or 0% to 100%, with higher scores indicating greater treatment expectancy and credibility.