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Background The traditional method of risk assessment for pre-eclampsia recommended by the National Institute for Health and Care Excellence is based on maternal factors and it recommends that high-risk women should be treated with aspirin. An alternative method of screening is based on the competing risk model, which uses Bayes’ theorem to combine maternal factors with mean arterial pressure, the uterine artery pulsatility index, serum placental growth factor and pregnancy-associated plasma protein-A at 11–13 weeks’ gestation. Objective The primary aim was to compare the performance of screening by risks obtained using the competing risk model with risk assessment using the National Institute for Health and Care Excellence guidelines. Design This was a prospective multicentre observational study. Setting The setting was seven NHS maternity hospitals in England. Participants Participants were women with singleton pregnancy attending for a routine hospital visit at 11+0–13+6 weeks’ gestation between April and December 2016. Main outcome measures The performance of screening for pre-eclampsia by the competing risk model was compared with the National Institute for Health and Care Excellence method. Relative reductions in risk with aspirin prophylaxis of 30% and 60% were assumed for all pre-eclampsia and preterm pre-eclampsia, respectively. The primary comparison was the detection rate of the National Institute for Health and Care Excellence method with the detection rate of a mini-combined test (including maternal factors, mean arterial pressure and pregnancy-associated plasma protein-A) in the prediction of all pre-eclampsia for the same screen-positive rate determined by the National Institute for Health and Care Excellence method. Results In 473 (2.8%) of the 16,747 pregnancies there was development of pre-eclampsia, including 142 (0.8%) women with preterm pre-eclampsia. The screen-positive rate by the National Institute for Health and Care Excellence method was 10.3%. For all pre-eclampsia, the false-positive and detection rates by the National Institute for Health and Care Excellence method were 9.7% and 31.6%, respectively. For preterm pre-eclampsia, the false-positive and detection rates were 10.0% and 42.8%, respectively. Compliance with the National Institute for Health and Care Excellence recommendation that high-risk women should be treated with aspirin from the first trimester was 23%. For the same screen-positive rate, the detection rate of the mini-combined test for all pre-eclampsia was 42.8%, which was superior to that of the National Institute for Health and Care Excellence method by 11.2% (95% confidence interval 6.9% to 15.6%). The increase in detection for the same screen-positive rate was accompanied by a reduction in false-positive rate of 0.3%. For the same screen-positive rate as National Institute for Health and Care Excellence, the detection rate for preterm pre-eclampsia by combining maternal factors, mean arterial pressure and placental growth factor was 67.3% compared with 44.1% with the National Institute for Health and Care Excellence method. With the addition of the uterine artery pulsatility index, the detection rate was 78.6%. This was higher than that of the National Institute for Health and Care Excellence method by 35.5% (95% confidence interval 25.2% to 45.8%). Calibration of risks for pre-eclampsia was generally good, with the calibration slope very close to 1.0. The feasibility of incorporating a new biomarker was demonstrated. However, the addition of inhibin A to the full combined test did not improve the detection rates for all pre-eclampsia and preterm pre-eclampsia (61% and 80%, respectively). The same screening model for preterm pre-eclampsia by a combination of maternal factors, mean arterial pressure, the uterine artery pulsatility index and placental growth factor achieved detection rates of 45.8% and 56.3%, respectively, for preterm small for gestational age and early small for gestational age neonates. Limitation The study did not include a health economic assessment. Conclusion The findings suggest that performance of screening for pre-eclampsia provided by a combination of maternal factors and biomarkers is superior to that achieved by current National Institute for Health and Care Excellence guidelines. Future work Future work is required to identify potential biomarkers for further improvement of the competing risk model and to carry out a health economic assessment. Trial registration Current Controlled Trials ISRCTN83611527. Funding This project was funded by the Efficacy and Mechanism Evaluation programme, a Medical Research Council and National Institute for Health Research (NIHR) partnership. This will be published in full in Efficacy and Mechanism Evaluation; Vol. 7, No. 8. See the NIHR Journals Library website for further project information.

BackgroundThere is an inherent tension in neonatal services between the efficiency and specialised care that comes with centralisation and the provision of local services with associated ease of access and community benefits. This study builds on previous work in South West England to address these issues at a national scale.Objectives(1) To develop an analytical framework to address key issues of neonatal service configuration in England, (2) to investigate visualisation tools to facilitate the communication of findings to stakeholder groups and (3) to assess parental preferences in relation to service configuration alternatives.Main outcome measuresThe ability to meet nurse staffing guidelines, volumes of units, costs, mortality, number and distance of transfers, travel distances and travel times for parents.DesignDescriptive statistics, location analysis, mathematical modelling, discrete event simulation and economic analysis were used. Qualitative methods were used to interview policy-makers and parents. A parent advisory group supported the study.SettingNHS neonatal services across England.DataNeonatal care data were sourced from the National Neonatal Research Database. Information on neonatal units was drawn from the National Neonatal Audit Programme. Geographic and demographic data were sourced from the Office for National Statistics. Travel time data were retrieved via a geographic information system. Birth data were sourced from Hospital Episode Statistics. Parental cost data were collected via a survey.ResultsLocation analysis shows that to achieve 100% of births in units with ≥ 6000 births per year, the number of birth centres would need to be reduced from 161 to approximately 72, with more parents travelling > 30 minutes. The maximum number of neonatal intensive care units (NICUs) needed to achieve 100% of very low-birthweight infants attending high-volume units is 36 with existing NICUs, or 48 if NICUs are located wherever there is currently a neonatal unit of any level. Simulation modelling further demonstrated the workforce implications of different configurations. Mortality modelling shows that the birth of very preterm infants in high-volume hospitals reduces mortality (a conservative estimate of a 1.2-percentage-point lower risk) relative to these births in other hospitals. It is currently not possible to estimate the impact of mortality for infants transferred into NICUs. Cost modelling shows that the mean length of stay following a birth in a high-volume hospital is 9 days longer and the mean cost is £5715 more than for a birth in another neonatal unit. In addition, the incremental cost per neonatal life saved is £460,887, which is comparable to other similar life-saving interventions. The analysis of parent costs identified unpaid leave entitlement, food, travel, accommodation, baby care and parking as key factors. The qualitative study suggested that central concerns were the health of the baby and mother, communication by medical teams and support for families.LimitationsThe following factors could not be modelled because of a paucity of data – morbidity outcomes, the impact of transfers and the maternity/neonatal service interface.ConclusionsAn evidence-based framework was developed to inform the configuration of neonatal services and model system performance from the perspectives of both service providers and parents.Future workTo extend the modelling to encompass the interface between maternity and neonatal services.FundingThe National Institute for Health Research Health Services and Delivery Research programme.