Factors Influencing Obstetric Nurses' Knowledge of Venous Thromboembolism Prevention: A Multicenter Cross-Sectional Study

Summary

This study assessed obstetric nurses’ knowledge of venous thromboembolism (VTE) prevention in China and analyzed associated influencing factors. Using a multicenter cross-sectional design, it identified knowledge gaps and key determinants, providing evidence to support targeted training and improved preventive strategies in obstetric care settings.

Abstract

This study aimed to assess obstetric nurses' knowledge of venous thromboembolism (VTE) prevention in China and to analyze influencing factors, with the goal of enhancing prevention efforts during pregnancy and the postpartum period. A total of 598 obstetric nurses from 154 hospitals across 29 provinces and cities participated in this study in August 2023. A self-designed questionnaire was employed to evaluate their knowledge of VTE and relevant factors. Multiple linear regression was used to examine the factors influencing obstetric nurses’ VTE knowledge. The average correct rate of obstetric nurses' VTE knowledge was 69.8%. Correct rates for mechanical and pharmacological prevention were 54.6% and 57.3%, respectively. A higher correct rate was observed among nursing managers and nurses who had received specific VTE-related training. The level of VTE prevention knowledge among obstetric nurses in China is suboptimal, with notable gaps identified in mechanical and pharmacological prevention strategies. Future initiatives should prioritize targeted, standardized training programs tailored to nurses' knowledge gaps, particularly in mechanical and pharmacological VTE prevention strategies.

Introduction

Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary thromboembolism (PTE), is a common complication among hospitalized patients and a significant cause of unexpected in-hospital deaths¹. Pregnant women face a four to five times higher risk of developing thromboembolic disease compared to non-pregnant women². Annually, approximately 78,000 pregnant women worldwide succumb to VTE during pregnancy and the postpartum period, making it the second leading cause of maternal mortality in developed countries³. Fortunately, VTE can be effectively prevented through appropriate prophylaxis, reducing disease risk and improving health outcomes. Therefore, it is crucial to ensure timely VTE prevention and treatment during pregnancy and the postpartum period to safeguard maternal safety.

Over the past decade, China has made significant progress in developing evidence-based consensus guidelines and national programs focused on VTE prevention and treatment during pregnancy and the postpartum period^4,5. However, research on VTE prevention and treatment during these periods is not limited to China alone. Internationally, numerous studies have enhanced our understanding of this topic. For instance, a review of international research has discussed knowledge gaps and existing approaches to postpartum VTE prevention, including ongoing pilot trials on VTE risk assessment, prevention, and diagnosis during pregnancy.

Nurses, as primary caregivers during hospitalization, play a critical role in early thrombosis risk assessment, identification of high-risk VTE patients, provision of targeted health education, and implementation of preventive measures⁶. This role is particularly vital in obstetric settings, where pregnancy induces a hypercoagulable state, venous stasis, and vascular injury—physiological changes that collectively elevate VTE risk through mechanisms distinct from those in surgical or medical patients². Studies indicate that the predominant barrier for nurses in performing VTE risk assessments is the lack of knowledge⁷. Nurses with expert knowledge can play a prominent role in influencing and implementing changes in health-care practices⁸. Therefore, increasing nurses' knowledge and awareness of VTE risks and prevention is essential to mitigate complications.

Currently, most research on nurses' knowledge of VTE prevention focuses on surgical, internal medicine, and intensive care unit nurses^3,9. However, few studies have specifically investigated obstetric nurses' knowledge of VTE prevention, despite the distinct pathophysiological mechanisms and heightened VTE risk associated with pregnancy. Existing studies are predominantly single‑center, employ small sample sizes, lack validated assessment instruments, and fail to systematically analyze influencing factors. These methodological limitations constrain the generalizability of findings and the development of targeted educational interventions. Accordingly, this study aims to investigate obstetric nurses' knowledge of VTE prevention and systematically identify its influencing factors, including demographic and work‑related variables. 

We hypothesize that (1) obstetric nurses' overall knowledge of VTE prevention will be suboptimal, and (2) factors such as longer work experience, higher professional title, and prior VTE‑related training will be positively associated with higher knowledge scores. The findings will assist nursing managers in developing standardized prevention protocols tailored to obstetric settings, ultimately reducing the incidence of perinatal VTE.

Protocol

The Medical Ethics Committee of the People's Hospital, Peking University, approved this study protocol before the survey was formed (approval number: 2024PHB018-001). Participation in this study was voluntary and anonymous.

Design and setting
This multi-center cross-sectional study was conducted from 1st to 31st August 2023 among obstetric nurses across Mainland China. In total, obstetric nurses from 154 hospitals spanning 29 provinces and cities participated in this study.

Participants
The sample size was calculated using an online tool (https://www.calculator.io/). As there is no data on the correct rate of VTE prevention knowledge among obstetric nurses, we estimated P (the correct rate of VTE prevention knowledge) at 61.3% based on a previous study¹⁰. The confidence interval was 95%, and the allowable error was set at 4%. The number of minimum sample sizes was 570. After screening the nurses for inclusion and exclusion criteria, a total of 604 obstetric nurses were enrolled in the study. Inclusion criteria for participants comprised: (a) aged ≥ 18 years old; (b) obtaining a Nursing Practice Certificate issued by the Ministry of Health of China; (c) at least one year of obstetric nursing experience; (d) provision of informed consent; and (e) voluntary participation in the study. Exclusion criteria encompassed nurses on extended vacation or still undergoing training.

Procedure
The survey was conducted online via an electronic link on the Sojump platform (http://www.wjx.cn/). Questionnaires were distributed via WeChat to head nurses of obstetrics departments at various hospitals and members of the Obstetrics Committee of the Chinese Nursing Association. A total of 604 obstetric nurses were invited to participate. Eligible participants received a link to a cover letter explaining the study's purpose, along with the informed consent form, and all responses were submitted anonymously. Nurses accessed the questionnaire within their departments and completed it on their own devices, without on-site supervision, to minimize potential response bias introduced by the researcher's presence. The questionnaire was designed so that it could not be submitted until all questions were answered, ensuring that no submissions were incomplete. A total of 604 questionnaires were collected, of which 598 were valid, yielding a valid response rate of 99% (598/604). Please refer to Figure 1 for details.

Measurements
The survey utilized the researcher-developed 'Obstetric Venous Thromboembolism Prevention and Nursing Knowledge Questionnaire'. The questionnaire was formulated based on a literature review, the latest guidelines on VTE care, and expert consultation^4,5,11,12,13. Seven experts were invited to evaluate content validity, including three nursing professors with expertise in obstetric nursing, two clinical obstetric nurse managers, and two vascular surgeons specializing in thromboembolic disease management. All experts held senior professional titles and had at least 10 years of experience in their respective fields. Experts independently reviewed the initial 78-item questionnaire using a four-point rating scale (1 = not relevant, 4 = highly relevant). The review was conducted in two rounds. After the first round, items with an item-level content validity index below 0.78 were revised or removed; items with ambiguous wording were refined based on expert comments. A second round confirmed the final item set. The questionnaire-level content validity index was 0.95, indicating excellent content validity. Prior to formal distribution, a pilot survey was conducted with 30 obstetric nurses. The pilot tested the clarity and comprehensibility of the questions. Internal consistency was assessed using Cronbach's α, yielding a coefficient of 0.899 for the total scale, indicating strong internal consistency. As the questionnaire was constructed on a clear theoretical framework and guideline-derived domains, confirmatory factor analysis was not conducted in this exploration phase; structural validity will be examined in subsequent large-scale validation studies.

The final questionnaire comprises two sections: personal general information (14 items) and VTE prevention knowledge (60 items). The general information section included sections on demographic information (province, city, hospital level, type of hospital, age, education level, professional title, years in obstetric nursing, and position), familiarity with VTE prevention guidelines, and specific training received. The knowledge section contains 60 items of five subscales on VTE prevention: basic knowledge (14 items), risk assessment (22 items), basic preventive measures (6 items), mechanical preventive measures (10 items), and pharmacological preventive measures (8 items). Responses were measured on a scale indicating correctness, with options for "correct", "incorrect", and "uncertain", assessing the participants' understanding and implementation of VTE prevention strategies. Each item scores 1 point for a correct answer and 0 points for an incorrect or uncertain answer. The total possible score ranges from 0 to 60 points, and the average dimension score is calculated as the dimension's average score divided by the total possible score, multiplied by 100%. An average scoring rate below 60% is deemed insufficient for nurses' knowledge in that dimension.

Statistical methods
Data analysis was conducted using IBM SPSS Statistics version 27.0. Descriptive statistics, including frequencies, percentages, means, and standard deviations, were used to summarize the data. Group comparisons for continuous variables were performed using t-tests or one-way ANOVA, while categorical data were analyzed using the χ² test. Multivariate linear regression was used to identify factors influencing VTE prevention knowledge scores. Categorical variables were transformed into dummy variables. The statistical significance level was set at p < 0.05 (two-sided).

Results

Participants’ general information
Out of the 598 nurses surveyed, 396 (66.2%) were from general hospitals. Among them, 528 held a bachelor's degree or higher, 346 held the title of Supervisor Nurse or higher, with an average of 11.50 ± 7.411 years of experience in obstetric nursing, and an average age of 34.47 ± 7.157 years. There were also 61 nursing managers. The extent of VTE training among obstetric nurses is detailed in Table 1. Specifically, 90.8% of participants received train...

Discussion

This study investigated obstetric nurses’ knowledge of VTE prevention and examined the factors associated with it. Pregnant women face a 4 to 5 times higher risk of developing thromboembolic disease compared to non-pregnant women². However, to our knowledge, few studies have examined obstetric nurses' knowledge of VTE prevention.

The results showed that obstetric nurses have a relatively higher score (69.8%) of VTE prevention knowledge than a previous national...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
IBM SPSS Statistics (Version 27.0)	IBM Corp., USA	https://www.ibm.com/spss	Used for statistical data analysis
Online Sample Size Calculator	Calculator.io	https://www.calculator.io/sample-size-calculator/	Used for sample size estimation
Sojump Online Survey Platform	Sojump (Wenjuanxing), China	https://www.wjx.cn/	Used for questionnaire distribution and data collection
WeChat Application	Tencent, China	https://www.wechat.com/	Used to distribute survey links to participants
Personal Digital Devices (smartphones/computers)	Various manufacturers	N/A	Used by participants to complete the questionnaire