Two-dose varicella vaccine effectiveness in China: a meta-analysis and evidence quality assessment
BMC Infectious Diseases·
- DOI
- 10.1186/s12879-021-06217-1
- PMID
- —
- PMCID
- —
- OpenAlex
- W3171485445
- Study type
- Meta-analysis
- Publisher
- Springer Science and Business Media LLC
- Article type
- journal-article
- Integrity
- current
Why this research matters now
The findings suggest that two-dose varicella vaccination is highly effective in preventing varicella and is recommended for countries seeking further control of the disease.
Structured evidence summary
Research question
The study evaluated the effectiveness of the two-dose varicella vaccine in healthy children aged 1–12 years in China and explored the application of the GRADE approach to assess evidence quality in observational vaccine effectiveness studies.
Study design
This was a meta-analysis of observational studies published from 1997 to 2019, including 12 studies and 87,196 individuals. Study quality was assessed using the Newcastle Ottawa Scale, and evidence quality was rated using the GRADE system.
Population and setting
The review included healthy children aged 1–12 years in China. Studies comprised both outbreak investigations and non-outbreak observational studies.
Main findings
The pooled two-dose vaccine effectiveness was 90% (95% CI: 69–97%). Effectiveness in outbreak studies (87%, 95% CI: 76–93%) was lower than in non-outbreak studies (99%, 95% CI: 98–99%). No significant difference in effectiveness was observed by Newcastle Ottawa Scale quality score. The overall quality of evidence was rated as low, while evidence from studies with NOS scores ≥7 was rated as moderate.
Public-health relevance
The findings suggest that two-dose varicella vaccination is highly effective in preventing varicella and is recommended for countries seeking further control of the disease.
Important limitations
The overall quality of evidence was rated as low due to limitations in the included studies and publication bias, though it was upgraded by two levels for large effect size. The authors note that higher quality evidence is needed to support stronger recommendations. This summary is limited to the supplied single-article abstract and metadata; the original paper is required for decision-grade interpretation.
GIDS interpretation
This meta-analysis was classified under varicella disease surveillance for China, with topics including outbreak investigation, vaccination, and vaccine effectiveness. It provides pooled estimates of two-dose vaccine effectiveness from Chinese observational studies and demonstrates methodological application of GRADE evidence assessment to vaccine effectiveness research.
Related GIDS surveillance
Literature context does not validate, explain, or change a surveillance signal. Exact and contextual relationships are shown separately.
Evidence relationships
This article has 8 auditable classifier relationships to diseases, places, topics, and study design.