ArticleAnnals of occupational and environmental medicine2017
The relationship between serum vitamin D levels and sleep quality in fixed day indoor field workers in the electronics manufacturing industry in Korea.
Article in Annals of occupational and environmental medicine, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
16 citing papers in PubMed, 1 synthesis or guideline pooled it, 41 citations in OpenAlex.
- The Association between Vitamin D Deficiency and Sleep Disorders: A Systematic Review and Meta-Analysis.Nutrients · 2018Pooled it
- Review
- Association between vitamin D level and sleep quality in the elderly population: a prospective cohort study.Sleep & breathing = Schlaf & Atmung · 2025Article
- Do not sleep on vitamin D: vitamin D is associated with sleep variability in apparently healthy adults.American journal of physiology. Regulatory, integrative and comparative physiology · 2025Article
- Vitamin D replacement therapy may regulate sleep habits in patients with restless leg syndrome.Open medicine (Warsaw, Poland) · 2025Article
- Serum vitamin D concentrations and sleep disorders: insights from NHANES 2011-2016 and Mendelian Randomization analysis.Sleep & breathing = Schlaf & Atmung · 2024Article
- The role of interaction between vitamin D and VDR FokI gene polymorphism (rs2228570) in sleep quality of adults.Scientific reports · 2024Article
- Influence of sunlight on the association between 25-hydroxyvitamin D levels and sleep quality in Brazilian adults: A population-based study.Nutrition (Burbank, Los Angeles County, Calif.) · 2023Article
- The association between vitamin D status and sleep duration in school-aged children; the CASPIAN-V study.Journal of diabetes and metabolic disorders · 2023Article
- Examination of correlations between vitamin D and melatonin levels with sleep among women aged 18-49 years.Central European journal of public health · 2023Article
- Associations of serum 25-hydroxyvitamin D and subjective sleep measures in an arctic population: Insights from the population-based Tromsø Study.Sleep medicine: X · 2022Article
- Sleep Quality: A Narrative Review on Nutrition, Stimulants, and Physical Activity as Important Factors.Nutrients · 2022Review
- No improvement of sleep from vitamin D supplementation: insights from a randomized controlled trial.Sleep medicine: X · 2021Article
- The effect of vitamin D on restless legs syndrome: prospective self-controlled case study.Sleep & breathing = Schlaf & Atmung · 2020Article
- Vitamin D and sleep in children.Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine · 2020Article
- Association of serum 25-hydroxyvitamin D concentrations with sleep phenotypes in a German community sample.PloS one · 2019Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
9 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundAlthough recent studies have investigated the influence of vitamin D on sleep patterns, there is a lack of research on the relationship between vitamin D and sleep patterns in Korean workers. This study focused on the relationship between serum vitamin D levels and sleep in fixed day indoor field workers in the electronics manufacturing industry in Korea.
methodsThe 1472 subjects who were included in this study were selected from fixed day workers in the electronics manufacturing industry who had received a worker's special health examination at a hospital in Changwon, South Gyeongsang Province between January 2015 and December 2015. Nighttime workers and those who showed symptoms of depression were excluded from this study. The sociodemographic and lifestyle variables of the participants were investigated, including age, sex, marital status, level of education, body mass index, smoking habits, alcohol consumption habits, and regular exercise. Work-related factors were evaluated, such as employee tenure and occupational stress. Serum 25-hydroxyvitamin D was measured as an indicator of vitamin D levels, and quality of sleep was evaluated using the Pittsburgh Sleep Quality Index (PSQI) translated into Korean.
resultsThe subjects had a mean serum vitamin D level of 13.70 ± 5.93 ng/mL. Vitamin D deficiency, defined as a serum vitamin D level of <10 ng/mL, was found in 24.8% of males and significantly more frequently in females (47.6%). Poor sleep quality was reported by 19.8% of participants with serum vitamin D levels ≥10 ng/mL and by 21.7% of those with serum vitamin D levels <10 ng/mL, which was a significant difference (
conclusionsThis study investigated serum vitamin D levels in fixed day indoor field workers in the manufacturing industry in Korea and analyzed the relationship of vitamin D deficiency with sleep quality. A significant correlation was found between serum vitamin D deficiency and poor sleep quality. Based on the results of this study, sleep disorder management for workers can be improved by providing regular examinations checking their serum vitamin D levels and supplying vitamin D to workers with serum vitamin D deficiency to enhance their quality of sleep.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.