SynthesisBMJ open2025
Vitamin D levels and its influencing factors in children and adolescents in mainland China: a systematic review and meta-analysis.
Synthesis in BMJ open, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.
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Who cites it
5 citing papers in PubMed.
- Vitamin D deficiency among apparently healthy adults in northern China: behavioral correlates and an indoor-lifestyle framework.Frontiers in public health · 2026Article
- High burden of vitamin D deficiency in Chinese university students: impact of sun protection culture.Frontiers in nutrition · 2026Article
- Pandemic-related changes in seasonal vitamin D disparities among preschool children: a community-based cross-sectional study.Frontiers in nutrition · 2026Article
- Prevalence and correlates of vitamin D deficiency in a mixed-age hospital-based cohort.Frontiers in public health · 2026Article
- Micronutrient Deficiency and Nutritional Status Among Indonesian Children Under Five Years of Age: Evidence from National Survey Data.Nutrients · 2025Article
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Authors and funding
5 authors.
Funding
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Abstract
objectivesChildhood vitamin D deficiency is a public health issue. This study aims to systematically evaluate vitamin D nutritional status among children and adolescents in Mainland China through a quantitative analysis of literature, providing evidence-based strategies for prevention.
designThis is a systematic review and meta-analysis, conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES: A comprehensive search strategy was implemented across eight electronic databases (PubMed, Embase, Web of Science, Cochrane Library, CNKI, VIP, Wanfang and CBM) from inception to February 2024. ELIGIBILITY CRITERIA: We included cross-sectional studies that measured serum 25-hydroxyvitamin D levels and analysed influencing factors (eg, age, season, region) in healthy children and adolescents aged 0-18 years in Mainland China; studies reporting prevalence data of vitamin D deficiency/insufficiency based on standardised thresholds (deficiency <50 nmol/L, insufficiency 50-75 nmol/L) and using validated detection methods (eg, liquid chromatography-tandem mass spectrometry, chemiluminescence immunoassay, ELISA) were prioritised. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers systematically searched, screened and extracted data using predefined protocols. Study quality was assessed with the Agency for Healthcare Research and Quality (AHRQ) tool. Meta-analyses were performed using random-effects models in Review Manager V.5.3 and Stata V.16.0, with subgroup analyses by age, season and region. Sensitivity analysis and Egger's test were applied to evaluate robustness and publication bias. Findings were synthesised through narrative summaries and quantitative pooling.
resultsThe pooled prevalence of vitamin D deficiency among children and adolescents in Mainland China was 48% (95% CI: 40% to 57%), with extreme heterogeneity across studies (I² = 99.98%, p<0.001). Sensitivity analysis confirmed the stability of pooled estimates. Subgroup analyses revealed significant age-related declines (infants: 82.35 nmol/L vs adolescents: 50.98 nmol/L, p<0.05). Study quality assessed by AHRQ criteria showed 16% of included studies were high-quality (scores 8-11/11), 84% moderate (4-7). Evidence of publication bias was detected via Egger's test (p<0.05) and funnel plot asymmetry.
conclusionsThe study highlights the widespread nature of vitamin D deficiency among children and adolescents in Mainland China, particularly in older children and during winter months. Effective interventions are necessary to address this issue. Future research should prioritise methodological standardisation to reduce heterogeneity and address potential publication bias. PROSPERO REGISTRATION NUMBER: CRD42023479183.
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