ArticleBMJ global health2022
The causal effect of delivery volume on severe maternal morbidity: an instrumental variable analysis in Sichuan, China.
Article in BMJ global health, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 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
10 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Efficacy and safety of PARP inhibitors in older patients with advanced ovarian cancer: a systematic review and network meta-analysis.Frontiers in oncology · 2026Pooled it
- Long-Term Effectiveness of a Mobile-Based Breastfeeding Program for Women with Gestational Diabetes: 6-Month Follow-Up of a Quasi-Experimental Study.Healthcare (Basel, Switzerland) · 2026Article
- Building a Machine Learning Model to Predict Postpartum Depression from Electronic Health Records in a Tertiary Care Setting.Journal of clinical medicine · 2025Article
- Exploring the influence of medical staffing and birth volume on observed-to-expected cesarean deliveries: a panel data analysis of integrated obstetric and gynecological departments in Germany.The European journal of health economics : HEPAC : health economics in prevention and care · 2025Article
- Mamba-fusion for privacy-preserving disease prediction.Scientific reports · 2025Article
- Risk factors for severe maternal morbidity in patients with hypertensive disorder of pregnancy: A retrospective study.Pakistan journal of medical sciences · 2025Article
- Identifying key indicators to develop a novel mobile application for early screening of postpartum depression in developing countries.BMC health services research · 2025Article
- Does the reduction in obstetric hospitals result in an unintended decreased in-hospital delivery utilisation? A causal multilevel analysis in China.BMJ public health · 2025Article
- The Effect of Oxidative Stress and Antioxidants Treatment on Gestational Diabetes Mellitus Outcome: A Scoping Review.Cell biochemistry and biophysics · 2024Article
- Spatial Access to Continuous Maternal and Perinatal Health Care Services in Low-Resource Settings: Cross-Sectional Study.JMIR public health and surveillance · 2024Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveFindings regarding the association between delivery volume and maternal health outcomes are mixed, most of which explored their correlation. This study aims to demonstrate the causal effect of delivery volume on severe maternal morbidity (SMM) in China.
methodsWe analysed all women giving birth in the densely populated Sichuan province with 83 million residents in China, during the fourth quarters of each of 4 years (from 2016 to 2019). The routinely collected discharge data, the health institutional annual report data and road network data were used for analysis. The maternal health outcome was measured by SMM. Instrumental variable (IV) methods were applied for estimation, while the surrounding average number of delivery cases per institution was used as the instrument.
resultsThe study included 4545 institution-years of data from 1456 distinct institutions with delivery services, reflecting 810 049 associated delivery cases. The average SMM rate was approximately 33.08 per 1000 deliveries during 2016 and 2019. More than 86% of delivery services were provided by a third of the institutions with the highest delivery volume (≥143 delivery cases quarterly). In contrast, less than 2% of delivery services were offered by a third of the institutions with the lowest delivery volume (<19 delivery cases quarterly). After adjusting the confounders in the IV-logistic models, the average marginal effect of per 1000 cases in delivery volume was -0.162 (95% CI -0.169 to -0.155), while the adjusted OR of delivery volume was 0.005 (95% CI 0.004 to 0.006).
conclusionIncreased delivery volume has great potential to improve maternal health outcomes, while the centralisation of delivery services might facilitate maternal health promotion in China. Our study also provides implications for other developing countries confronted with similar challenges to China.
Indexed as
Identifiers
What Socratic 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 Socratic graph.