concept

China Health and Retirement Longitudinal Study

Also known as: CHARLS

Facts (48)

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Associations Between Sleep Duration and Cognitive Function ... humanfactors.jmir.org JMIR Human Factors 27 facts

procedureThe Telephone Interview of Cognitive Status and the pentagon-drawing test in the CHARLS study assessed mental intactness by measuring time orientation, numerical ability, and visuospatial skills through tasks such as serial subtractions, identifying the current date, and replicating a drawing of overlapping pentagons, resulting in a mental intactness score ranging from 0 to 11.

formulaThe global cognitive function score in the CHARLS study was calculated as the sum of the episodic memory score and the mental intactness score, with higher scores indicating better cognitive performance.

claimThe CHARLS study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline for its cross-sectional analysis.

procedureThe CHARLS study used ANOVA for numerical variables, and ordered t-tests and chi-square tests for discrete variables to compare respondent characteristics among short, standard, and long sleep groups.

measurementIn the 2020 China Health and Retirement Longitudinal Study, sleep durations of 4 hours or less (β=−1.85), 5 hours (β=−0.55), 9 hours (β=−1.78), and 10 hours or more (β=−3.01) per night were significantly negatively associated with cognitive function.

measurementThe 2020 wave of the China Health and Retirement Longitudinal Study (CHARLS) included 19,816 individuals to investigate the associations between sleep duration and cognitive function.

claimThe China Health and Retirement Longitudinal Study is abbreviated as CHARLS.

claimThe CHARLS study categorizes sleep duration into three groups: a standard sleep group (7 to 8 hours), a short sleep group (less than 7 hours), and a long sleep group (more than 8 hours).

referenceThe study titled 'Associations Between Total Sleep Duration and Cognitive Function Among Middle-Aged and Older Chinese Adults' investigated the relationship between total sleep duration, midday napping, and cognitive function using data from the 2015 China Health and Retirement Longitudinal Study (CHARLS).

claimThe China Health and Retirement Longitudinal Study (CHARLS) subdivides cognitive function into mental intactness and episodic memory to provide evidence for improving cognitive health among middle-aged and older people.

procedureThe CHARLS study assessed daytime napping patterns by asking participants, 'In the past month, how long have you napped on average after lunch?' and categorized responses into 4 groups: nonnappers (0 min), short nappers (<30 min), moderate nappers (30-90 min), and extended nappers (>90 min).

perspectiveThe authors of the China Health and Retirement Longitudinal Study (CHARLS) hypothesize that both short and longer sleep durations are strongly associated with cognitive decline.

referenceThe CHARLS study collected sociodemographic and health-related data using a structured questionnaire, including covariates such as age, sex, educational attainment, marital status, residence, smoking and drinking status, visual and hearing impairment, self-reported general health status, self-reported life satisfaction, daytime napping habits, depression, and chronic disease condition.

measurementThe study participants in the 2020 China Health and Retirement Longitudinal Study had an average age of 61.5 years (SD 9.27), with 53.02% (8,232) being female and 46.98% (7,294) being male.

procedureThe CHARLS study gathered self-reported sleep duration data through face-to-face interviews using an open-ended question: 'In the past month, how many hours of sleep have you had on average per night?'

procedureThe CHARLS study used a generalized linear model with a Gaussian distribution and an identity link function for continuous cognitive measures.

referenceThe study 'High-intensity physical activity is not associated with better cognition in the elder: evidence from the China health and retirement longitudinal study' was posted as a preprint on Research Square on August 18, 2021.

claimThe China Health and Retirement Longitudinal Study team provided data and training for the research study.

referenceThe China Health and Retirement Longitudinal Study (CHARLS) cohort profile was published in the International Journal of Epidemiology in February 2014.

measurementThe CHARLS study categorized self-reported sleep duration into 7 groups: ≤4, 5, 6, 7, 8, 9, and ≥10 hours per evening.

referenceGuo et al. (2016) conducted a cross-sectional study using data from the China Health and Retirement Longitudinal Study (CHARLS) 2011-2012, which identified gender- and age-specific associations between sleep duration and prevalent hypertension in middle-aged and elderly Chinese populations.

measurementThe CHARLS study conducted all data analyses using Stata software, version 18.0.

measurementThe 2020 China Health and Retirement Longitudinal Study found that the negative impact of long sleep (≥10 hours) on overall cognitive function was the most pronounced (β=−3.01, 95% CI −3.39 to −2.63; P<.001), followed by extremely short sleep (≤4 hours; β=−1.85, 95% CI −2.07 to −1.62; P<.001).

procedureThe CHARLS study utilized sample weights during analysis to adjust for the representativeness of the sample.

procedureThe CHARLS study evaluated cognitive performance using three composite measures: the word recall test, the Telephone Interview of Cognitive Status, and a pentagon-drawing test.

claimThe 2020 China Health and Retirement Longitudinal Study identified an inverted U-shaped relationship between sleep duration and global cognitive decline, suggesting that cognitive function should be monitored in individuals with both short and long sleep durations.

measurementThe CHARLS study set statistical significance at a 2-sided P-value of less than .05.

U shaped association between sleep duration and long ... nature.com Nature by F Feng · 2025 11 facts

referenceThe China Health and Retirement Longitudinal Study (CHARLS) conducted biennial surveys from 2011 to 2020 to track cognitive trajectories over a 9-year period.

referenceZhao, Y., Hu, Y., Smith, J. P., Strauss, J., and Yang, G. authored the study 'Cohort profile: the China health and retirement longitudinal study (CHARLS)', published in the International Journal of Epidemiology in 2014.

measurementIn the China Health and Retirement Longitudinal Study (CHARLS), individuals with short sleep duration (< 6 hours) had an odds ratio (OR) of 1.17 (95% CI: 1.04–1.31) for incident cognitive decline.

claimThe China Health and Retirement Longitudinal Study (CHARLS) identified a U-shaped relationship between sleep duration and incident cognitive decline (nonlinear, p < 0.001).

measurementThe China Health and Retirement Longitudinal Study (CHARLS) cohort consisted of 8,668 participants with a mean age of 56.3 years, of whom 45.7% were female.

measurementIn the China Health and Retirement Longitudinal Study (CHARLS), individuals with long sleep duration (> 8 hours) had an odds ratio (OR) of 1.57 (95% CI: 1.31–1.89) for incident cognitive decline.

measurementWhen sleep duration equaled or exceeded 7.23 hours, an increase in sleep duration significantly elevated the risk of cognitive decline (OR = 1.31, 95% CI: 1.17–1.46) according to the China Health and Retirement Longitudinal Study (CHARLS).

measurementWhen sleep duration was below 7.23 hours, an increase in sleep duration significantly reduced the risk of cognitive decline (OR = 0.90, 95% CI: 0.86–0.95) according to the China Health and Retirement Longitudinal Study (CHARLS).

claimThe China Health and Retirement Longitudinal Study (CHARLS) suggests that screening and brief counseling for short (< 6 h) and long (> 8 h) sleep, alongside promotion of sleep hygiene and assessment for treatable sleep disorders, may offer scalable strategies to support healthy cognitive aging.

measurementAmong the 8,668 participants in the China Health and Retirement Longitudinal Study (CHARLS), 34.24% exhibited cognitive decline, while 65.76% maintained stable cognition over the 9-year study period.

claimThe China Health and Retirement Longitudinal Study (CHARLS) investigates the association between baseline sleep duration and cognitive decline trajectories among cognitively normal participants using group-based trajectory modeling (GBTM) over a 9-year follow-up period.

Improvement in sleep duration was associated with higher cognitive ... aging-us.com Aging Oct 20, 2020 9 facts

measurementIn Wave 1 of the China Health and Retirement Longitudinal Study (CHARLS), the mean age of all participants was 59.1 ± 9.8 years.

referenceThe China Health and Retirement Longitudinal Study (CHARLS) is a nationally representative longitudinal study conducted by Peking University among adults aged 45 and older in China.

measurementIn Wave 1 of the China Health and Retirement Longitudinal Study (CHARLS), the mean nocturnal sleep duration of participants was 6.4 ± 1.9 hours per night.

referenceA 2019 study by Qin et al. using data from the China Health and Retirement Longitudinal Study (CHARLS) identified an association between anemia and cognitive decline among middle-aged and elderly Chinese individuals.

measurementIn Wave 1 of the China Health and Retirement Longitudinal Study (CHARLS), 73.3% of the participants attended primary school and above.

referenceThe global cognition score used in the China Health and Retirement Longitudinal Study (CHARLS) assessed episodic memory, visuospatial abilities, calculation, orientation, and attention.

measurementThe Biomedical Ethics Review Committee of Peking University granted ethics approval for data collection in the China Health and Retirement Longitudinal Study (CHARLS) under IRB number IRB00001052-11015.

referenceA 2014 study by Lei et al. analyzed health outcomes and socio-economic status among the mid-aged and elderly in China using the China Health and Retirement Longitudinal Study (CHARLS) national baseline data.

measurementIn Wave 1 of the China Health and Retirement Longitudinal Study (CHARLS), 47.3% of the participants were male, 76.5% were from rural areas, and 88.0% were married.

Associations Between Total Sleep Duration and Cognitive Function ... dovepress.com Wang Q, Zhu H, Dai R, Zhang T · Dove Medical Press Feb 10, 2022 1 fact

referenceLi et al. (2017) investigated the relationship between afternoon napping and cognition in Chinese older adults using baseline assessment data from the China Health and Retirement Longitudinal Study, as published in the Journal of the American Geriatrics Society.