STRUCTURED ABSTRACT
Background
Risk assessment models (RAMs) are used to select women at increased risk of venous thromboembolism (VTE) during pregnancy and the puerperium for thromboprophylaxis.
Objective
To estimate the value of potential future studies that would reduce the decision uncertainty associated with offering thromboprophylaxis according to available RAMs in the following groups: high-risk antepartum women (e.g. prior VTE), unselected postpartum women and postpartum women with risk factors (obesity or caesarean delivery).
Methods
A decision analytic model was developed to simulate clinical outcomes, and life-time costs and quality-adjusted life-years (QALYs), for different thromboprophylaxis strategies including thromboprophylaxis for all, thromboprophylaxis for none and RAM-based thromboprophylaxis. Expected value of perfect information (EVPI) analysis was used to determine which factors are associated with high decision uncertainty. The value of future research studies was estimated using expected value of sample information analysis (EVSI). Costs were assessed from a health and social services perspective.
Results
EVPI analysis identified high decision uncertainty for high-risk antepartum women (£21.8 million) and obese postpartum women (£13.4 million), which was largely attributable to uncertainty regarding the effectiveness of thromboprophylaxis in reducing VTE. A randomised controlled trial of thromboprophylaxis compared to none in obese postpartum women is likely to have substantial value (£2.8 million; 300 participants per arm). A trial in women with previous VTE would have higher value but would be less acceptable.
Conclusions
Future research should focus on estimating the effectiveness of thromboprophylaxis in obese postpartum women with additional risk factors, who have not had a previous VTE.
Keywords
Cost-benefit analysis
Heparin
Low-molecular-Weight
Pregnancy
Risk Factors
Venous thromboembolism
© 2024 The Author(s). Published by Elsevier Inc. on behalf of International Society on Thrombosis and Haemostasis.
