Poor Sleep by Population: Prevalence and What the Trials Found
Dinis 2018 (systematic review) reports poor sleep quality affecting 10-50% of college students, and pooled prevalence meta-analyses report poor sleep quality in 51% of police officers (Garbarino 2019), 69% of military personnel and veterans (Bai 2023) and 52.30% of pregnant women in Ethiopia (Zeleke 2024). Meta-analyses report CBT-I effective in menopausal women (Moon 2025), pregnant women (Zheng 2022; Visvanathan 2025) and daytime workers (Takano 2023), and possibly effective in older adults (Huang 2022); in shift workers Slanger 2016 could not determine whether interventions reduce sleepiness, and Nickel 2025 reports student sleep-education programs improved knowledge and sleep quality but not sleep duration.
What the evidence says
The sources on this entry are prevalence meta-analyses of poor sleep in specific populations and syntheses and trials of sleep interventions in those populations. On prevalence, Dinis 2018 (systematic review) reports poor sleep quality affecting 10-50% of college students and a bidirectional relationship between sleep quality and depression in this group, though it concludes that the relationship remains difficult to interpret. Garbarino 2019 (meta-analysis, 13 articles, 3,722 police officers) reports a pooled prevalence of bad sleep quality of 51%, with associations with work seniority and shift work. Bai 2023 (meta-analysis, 59 studies, 28,100 participants) reports a pooled prevalence of poor sleep quality of 69.00% among military personnel and veterans, 57.79% in active duty and 82.88% in veterans. Zeleke 2024 (meta-analysis, 7 studies, 2,689 participants) reports a pooled prevalence of 52.30% among pregnant women in Ethiopia, associated with depression, stress, age and anxiety. On CBT-I in specific groups, Moon 2025 (meta-analysis, 11 randomised trials) reports that CBT-I significantly improved sleep quality (SMD -1.01) and reduced insomnia severity in menopausal women, regardless of delivery mode. Zheng 2022 (meta-analysis, 8 randomised trials, 743 pregnant women) and Visvanathan 2025 (meta-analysis, 12 studies) report CBT-I efficacious for insomnia, sleep quality and mood symptoms in pregnancy, with evidence for other psychoeducational interventions limited. Huang 2022 (meta-analysis, 14 studies) reports significant pooled effects on sleep efficiency, sleep-onset latency and wake after sleep onset in older adults and concludes that CBT-I may be an effective approach for insomnia in this group. Yu 2025 (umbrella review, 19 systematic reviews) reports that CBT and Tai Chi effectively improve sleep in older adults. Takano 2023 (meta-analysis, 21 studies) reports both web-based and face-to-face CBT-I effective for insomnia in daytime workers, with only face-to-face achieving clinically meaningful change and the effect for shift workers undetermined. Vega-Escaño 2020 (meta-analysis, 12 studies, 827 workers) reports a moderate effect of workplace insomnia interventions, mostly CBT, on insomnia symptoms. In shift and night workers, Dugdale 2022 (systematic review, 7 intervention studies) reports substantial evidence that bright-light treatments improve night-shift alertness and insufficient evidence for blue-light blocking glasses and sleep hygiene or alertness training. Slanger 2016 (Cochrane meta-analysis, 17 trials, 556 participants) reports inconclusive results, with bright light at night reducing sleepiness by 0.83 points on very low quality evidence, and concludes that it is not possible to determine whether these interventions reduce sleepiness or improve sleep. Järnefelt 2019 (randomised trial) reports no significant differences between CBT-I interventions and a sleep hygiene control for sleep improvement, with group-based CBT-I possibly alleviating mood symptoms. For caregivers, Ruan 2025 and Ruan 2026 (meta-analyses, 21 randomised trials, 1964 caregivers) report that non-pharmacological interventions may improve sleep quality in dementia and informal caregivers, with confidence limited by high risk of bias and very low certainty. For student sleep education, Dietrich 2016 (systematic review, 4 studies) reports mixed results and insufficient evidence to determine effectiveness on knowledge, behaviour or sleep quality, while Nickel 2025 (meta-analysis, 15 studies sharing data) reports interventions improved sleep knowledge (g = 0.69) and sleep quality (g = 0.25) but not sleep duration, with similar effects across student groups.
- Myth: Teaching people about sleep improves their sleep. Actually: the review reports that sleep-education programs reliably raise knowledge but inconsistently improve sleep quality and rarely change sleep duration.
- Does not diagnose, treat, or cure any disease or injury
- Not a substitute for individualized medical or physical-therapy advice
- Results vary between individuals; no guaranteed outcome
- Agreement
- Direction recorded for 0 of 18 sources; not yet recorded for the rest.
- The claim's outcome
- Outcome not yet recorded
- Certainty
- A source states a certainty rating for 2 outcomes.
- Authors
- Sources share authors: J. Ruan (first author of 2 sources).
- How the sources were read
- Some sources are based on abstracts, not full texts.
What each source measured and concluded (18)
- What it measured
- Effectiveness of CBT-I on insomnia symptoms in workers
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of RCTs
- Studies and participants, as stated
- 21 studies
- What it measured
- Sleep quality and insomnia severity
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of RCTs
- Studies and participants, as stated
- 11 RCTs; n=973
- What it measured
- Sleep quality (PSQI) prevalence among police officers
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis
- Studies and participants, as stated
- 13 articles; 3,722 police officers (from 1,149 studies)
- What it measured
- Insomnia Severity Index and Pittsburgh Sleep Quality Index
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of RCTs
- Studies and participants, as stated
- 8 RCTs; 743 pregnant women
- What it measured
- Relationship between sleep quality and depression
- How it was read
- screened only, not extracted
- What it measured
- Global prevalence of poor sleep quality
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of epidemiological studies
- Studies and participants, as stated
- 59 studies; N=28,100
- What it measured
- Effect of psycho-educational interventions on sleep in pregnancy
- How it was read
- screened only, not extracted
- What the review says it includes
- Integrative review with meta-analysis (RCT subset)
- Studies and participants, as stated
- 12 studies
- What it measured
- Pooled prevalence of poor sleep quality and associated factors
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis
- Studies and participants, as stated
- 7 studies; 2,689 participants
- What it measured
- Sleep quality measured by Pittsburgh Sleep Quality Index (PSQI), mean difference
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of RCTs
- Studies and participants, as stated
- 21 RCTs, 1964 adults (74.94% female)
- What it measured
- Sleep quality measured by Pittsburgh Sleep Quality Index (PSQI)
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of RCTs
- Studies and participants, as stated
- 21 RCTs, 1964 caregivers (mean age 64.06 years; 74.94% female); 5 studies/334 caregivers in pooled analysis
- What it measured
- Insomnia severity (Insomnia Severity Index)
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis
- Studies and participants, as stated
- 22 studies in review, 12 in meta-analysis (14 intervention groups, 827 workers)
- Heterogeneity, as stated
- Moderate effect for reducing insomnia symptoms post-intervention (MD -2.08, 95% CI -2.68 to -1.47), with non-significant heterogeneity (I2=0%)
- What it measured
- Sleep parameters (sleep efficiency, SOL, WASO, total sleep time)
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis (14 studies)
- Studies and participants, as stated
- 14 studies
- What it measured
- Sleep improvement (effectiveness of non-pharmacological interventions)
- How it was read
- screened only, not extracted
- What the review says it includes
- Umbrella review of systematic reviews with meta-analyses of RCTs (with evidence map)
- Studies and participants, as stated
- 19 systematic reviews comprising 160 RCTs
- What it measured
- Sleep hygiene knowledge, sleep hygiene behavior, and/or sleep quality
- How it was read
- based on the abstract, not the full text
- What the review says it includes
- Systematic review (of RCTs and quasi-experimental studies)
- Studies and participants, as stated
- 4 studies (3 RCTs, 1 quasi-experimental)
- What it measured
- Sleep knowledge, sleep quality, and sleep duration
- How it was read
- based on the abstract, not the full text
- What the review says it includes
- Content review and meta-analysis
- Studies and participants, as stated
- 36 studies identified (15 shared data, N=599); 21 programs reviewed
- What it measured
- Effects of fatigue interventions on alertness/sleep
- How it was read
- based on the abstract, not the full text
- What the review says it includes
- Systematic review (PRISMA)
- Studies and participants, as stated
- 7 intervention studies (from 1651 screened)
- What it measured
- Sleepiness at work and sleep length/quality between shifts
- How it was read
- based on the abstract, not the full text
- What the review says it includes
- Systematic review and meta-analysis (Cochrane; of RCTs including crossover)
- Studies and participants, as stated
- 17 trials, 556 participants
- What it measured
- Insomnia severity and sleep-related outcomes (questionnaires, sleep diary, actigraphy) after intervention and at 6-month follow-up
- How it was read
- screened only, not extracted
Certainty ratings the sources state (2)
- Rating, as the source states it
- low
- Framework
- not named by the source
- Applies to
- Given methodological diversity and low-quality evidence, it is not possible to determine whether these interventions reduce sleepiness or improve sleep; better powered RCTs needed
- Stated by
- Slanger et al. (2016)
- Rating, as the source states it
- very low
- Framework
- not named by the source
- Applies to
- Non-pharmacological interventions may improve sleep quality in dementia caregivers, but confidence is limited by high risk of bias and very low certainty of evidence
- Stated by
- Ruan et al. (2025)
Each source below is shown with its study design and a link to the original study, or, where it is not a completed research paper, with what kind of record it is; those are not counted. This is the audit trail.
Why do some records show a record type instead of a study design?
A study design is shown for a completed, peer-reviewed paper. A registered protocol, a preprint, a conference abstract, a referee report or a book chapter has not been through peer review as a finished paper, so it is labelled for what it is, and it is counted in no source count. Where a record could not be confirmed as a completed paper at all, it says so rather than guessing. They all stay in the list, and their DOI still resolves, because the count of what was screened is part of the audit trail.
- Protocol / registration A registered plan for a review or trial, not its results.
- Preprint Posted by its authors before peer review.
- Conference abstract A conference summary rather than a peer-reviewed paper.
- Peer-review report A referee's report on a paper, not the paper itself.
- Guideline / position stand A recommendation derived from evidence, which is a step further from the data than the evidence itself.
- Book chapter A chapter in a scholarly book rather than a journal paper.
- Type not recorded Our record does not say what kind of publication this is, so it is counted in no source count. That is a gap in our data, not a judgement about the research.
“Abstract only” means the review read that paper’s abstract, not its full text; “screened only” means it was included at re-screening and not extracted. Both stay in the trail with their DOI, because how a source was read is part of the audit.