BACKGROUND

Postpartum haemorrhage (PPH) is a major cause of maternal mortality worldwide. Previous studies have presented varying conclusions regarding the PPH risk in pregnant haemophilia carriers or women with von Willebrand disease (VWD). We aimed to evaluate PPH occurrence in this demographic using a nationwide inpatient database in Japan.

METHODS

In this retrospective study, we identified women aged 15–49 years who gave birth while hospitalised between July 2010 and March 2021, using the Japanese Diagnosis Procedure Combination database. These pregnant women were categorised into three groups: the haemophilia, VWD, and control cohort groups. The assessed outcomes were PPH and interventions for bleeding. Multivariable logistic regression analyses were performed to assess the association between coagulation disorders and patient outcomes.

RESULTS

We identified 113 pregnant women in the haemophilia group, 184 in the VWD group, and 1,459,451 in the control group. The outcomes of multivariable logistic regression analyses demonstrated that PPH occurrence was not higher in the haemophilia group (odds ratio, 0.74; 95% confidence interval, 0.46–1.17) than in the control group. Conversely, the VWD group was significantly associated with PPH (odds ratio, 1.46; 95% confidence interval, 1.05–2.02) and a higher incidence of interventions for bleeding (odds ratio, 2.49; 95% confidence interval, 1.55–4.00).

CONCLUSIONS

Despite the absence of a substantial correlation between haemophilia and PPH in pregnant haemophilia carriers, a discernible association emerged between VWD and PPH in pregnant women. Healthcare providers need to be mindful of the high prevalence of undiagnosed VWD and prepare adequately for delivery.

BACKGROUND

Childhood vaccinations can be effective for preventing not only infectious diseases but also other diseases and traumas. This is because vaccines may have nonspecific immunological effects. Additionally, visits for vaccinations may benefit doctors in promoting the overall health of children. We assessed whether vaccination status at 24 months was associated with the incidence of all-cause hospitalization.

METHODS

This retrospective cohort study used the vaccine records and healthcare claims from a Japanese city. We included children born between April 2014 and December 2020. Children who took all the following vaccine doses covered by the national immunization program at 24 months of age were defined as having an age-appropriate vaccination status: four doses of Hemophilus influenza type b, four of 13-valent pneumococcal conjugate, four of diphtheria, tetanus, acellular pertussis, and inactivated polio, three of hepatitis B virus, one of Bacille de Calmette et Guérin, one of measles and rubella, and one of varicella-zoster virus. A Cox regression model compared all-cause hospitalizations between children with and without age-appropriate vaccination, adjusting for sex, birth year, and comorbidities.

RESULTS

We identified 2,492 children: 1,689 were age-appropriate vaccinated, and 803 were not. There was no significant difference in all-cause hospitalizations (adjusted hazard ratio, 0.93; 95% confidence interval, 0.69 to 1.3; P = 0.65).

CONCLUSIONS

The effect of age-appropriate vaccinations on the overall health of children may be small.

BACKGROUND

Routinely collected medical data, such as electronic medical records (EMRs) and medical claims, are necessary for developing disease registries. This study aimed to develop an otologic surgery registry by integrating data from EMRs, medical claims, and otorhinolaryngology department information systems (ORL-DIS) and to assess the agreement of hearing tests between registry-determined evaluations (RDE) and surgeon-determined evaluations (SDE).

METHODS

A stapes surgery registry was developed by linking data from ORL-DIS, EMRs, and medical claims from two hospitals in Japan. SDE were recorded by the surgeons, whereas RDE were automatically assigned by the registry system. This study focused on pre- and postoperative hearing evaluations. Pure-tone averages (PTA) for air conduction (AC) and bone conduction (BC) were calculated. Agreement between SDE and RDE was assessed using Bland–Altman plots, and mean differences and 95% limits of agreement (95% LoA) were calculated. In SDE, cases with incomplete data were excluded.

RESULTS

A total of 164 patients (187 cases) were included. The Bland–Altman analysis revealed a high agreement between preoperative AC-PTA (mean difference: −1.61 dB; 95% LoA: −12.5 to 9.29 dB) and BC-PTA (mean difference: −1.05 dB; 95% LoA: −13.9 to 11.8 dB) measurements by SDE and RDE. Additionally, postoperative improvements showed a moderate agreement. The integration of audiometric data into the registry significantly reduced manual errors.

CONCLUSION

This study successfully established the first otologic surgery registry in Japan that integrates audiometric data from EMRs. This registry provides a valuable resource for analyzing surgical outcomes and a framework for future otologic research.

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a vital intervention in patients with severe cardiogenic shock or respiratory failure who are unresponsive to conventional therapies. Despite advances in ECMO technology and management, complications such as infections, renal dysfunction, and post-intensive care syndrome remain significant challenges that contribute to high mortality. Existing registries have provided valuable insights but lack detailed data on infection management, rehabilitation practices, and other granular aspects of ECMO care. The Japan Intensive Care ECMO Consortium: Nationwide Effort for ECMO Care Optimization and Excellence (ECMO NEXT) study aims to address these gaps by establishing a comprehensive multicenter study in Japan.

METHODS

This is a multicenter, retrospective cohort study conducted at 22 healthcare institutions in Japan, with data collected on ECMO cases between January 2018 and December 2023. Adults aged ≥18 years who underwent ECMO in the intensive care unit (ICU) during this period will be eligible. This study will focus on six predefined themes: post-decannulation fever, infection epidemiology, ventilator settings, ECMO-associated acute kidney injury and electrolyte abnormalities, rehabilitation practices, and venoarterial ECMO in toxicological emergencies and septic shock scenarios. Data—including clinical course, laboratory results, rehabilitation details, and outcomes—will be collected using a standardized electronic case report form on the Research Electronic Data Capture platform. Statistical models, including propensity score-based analyses, will be used to adjust for confounders and assess attributable risks.

CONCLUSIONS

The ECMO NEXT study provides high-resolution data to address the gaps in ECMO research, particularly in ICU management and post-ECMO recovery.

Secondary analyses of randomized controlled trials (RCTs) offer an efficient way to maximize the value of existing trial data and explore clinical questions beyond the original trial scope. This review outlines methodological considerations and best practices, emphasizing their role in evidence-based medicine. We describe major RCT data sources and summarize steps for accessing individual participant data. Key methods include formulating research questions, understanding trial design, data processing, statistical analysis, and clinical interpretation. Types of secondary analyses are discussed including subgroup analysis, biomarker studies, health economics, methodological research, adverse event analysis, and predictive modeling. Common challenges, such as data applicability, missingness, generalizability, and multiple testing, are summarized. With advances in data sharing, secondary analyses are expected to drive scientific discovery and provide more evidence for diagnosis and treatment patterns as long as rigorous standards and transparency are maintained.