TY - JOUR
T1 - External validation and clinical usefulness of first-trimester prediction models for small- and large-for-gestational-age infants
T2 - a prospective cohort study
AU - Meertens, L. J. E.
AU - Smits, L. J. M.
AU - van Kuijk, S. M. J.
AU - Aardenburg, R.
AU - van Dooren, I. M. A.
AU - Langenveld, J.
AU - Zwaan, I. M.
AU - Spaanderman, M. E. A.
AU - Scheepers, H. C. J.
N1 - Funding Information:
The Expect Study I was funded by The Netherlands Organization for Health Research and Development, Pregnancy and Childbirth program (ZonMw grant 209020007). The funding organization had no role in the design and conduct of the study, analysis or interpretation of data, decision to publish, or preparation of the manuscript. We thank all of the women who participated in the Expect Study I. The Expect Study I could not have been established without the contribution of the participating departments of obstetrics and gynaecology of hospitals, midwifery practices, and maternity care centres in the Province of Limburg: Zuyderland Medical Centre Heerlen and Sittard-Geleen, Maastricht University Medical Centre, Laurentius Hospital Roermond, Sint Jans Gasthuis Weert, VieCuri Medical Centre, midwifery practice Roermond, midwifery practice Nederweert, midwifery practice Weert, midwifery practice Lenie & Chantal, midwifery practice Loes Wijnhoven, midwifery practice De Roerstreek, midwifery practice Bollebuik, midwifery practice Westenberg, midwifery practice Cranendonck, midwifery practice Becca, midwifery practice Born, midwifery practice Geleen, midwifery practice Grevenbicht, midwifery practice Sittard, midwifery practice Sittard-Oost, midwifery practice Stein, midwifery practice Astrea, midwifery practice Horst & Maasdorpen, midwifery practice Reuver-Tegelen, midwifery practice Janneke van Hal, midwifery practice Raijer & Sup, midwifery practice Venlo-Blerick, midwifery practice Venray, midwifery practice Schoffelen-Van Vleuten, midwifery practice Maastricht, midwifery practice Meerssen, midwifery practice Naomi Satijn, midwifery practice Vita, midwifery practice Het Verloskundig Huis, midwifery practice Valkenburg, midwifery practice Parkstad, midwifery practice Lief, midwifery practice Bevalt Beter, midwifery practice ‘t Bolleke, midwifery practice Natuurlijk bij Jeanny, midwifery practice La Vie, GroenekruisDomicura, Cicogna, ZiNkraamzorg, and maternity centre Echt.
Funding Information:
We performed a multicentre prospective cohort study in the south-eastern part of the Netherlands (Expect Study I). The primary objective of this study was to validate published first-trimester prediction models for several adverse pregnancy outcomes. Six hospitals and 36 midwifery practices recruited pregnant women aged ≥18 years old at <16 weeks of gestation between 1 July 2013 and 1 January 2015, with follow-up continuing until 31 December 2015. Eligible pregnant women were invited to complete two web-based questionnaires (paper-based questionnaires were available, upon request): one before 16 weeks of gestation (pregnancy questionnaire) and one 6 weeks after the due date (postpartum questionnaire). Medical records and discharge letters were requested from health care providers. Pregnancies ending in miscarriage (<16 weeks of gestation), terminations of pregnancy before 24 weeks of gestation, and women lost-to-follow-up were excluded. For this study, we also excluded multiple pregnancies and women who delivered between 16+0 and 25+0 weeks of gestation, as the customised birthweight curves are only available from 25 weeks of gestation onwards.49 A detailed description of Expect Study I has been published in full elsewhere.48 Patients were involved in the development of the recruitment process and the study questionnaires. The design, results, and conclusions of this pilot study are described in the published study protocol.48 The study was funded by The Netherlands Organization for Health Research and Development (ZonMw grant 209020007).
Publisher Copyright:
© 2018 The Authors BJOG: An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd on behalf of Royal College of Obstetricians and Gynaecologists
PY - 2019/3
Y1 - 2019/3
N2 - ObjectiveTo assess the external validity of all published first-trimester prediction models based on routinely collected maternal predictors for the risk of small- and large-for-gestational-age (SGA and LGA) infants. Furthermore, the clinical potential of the best-performing models was evaluated.DesignMulticentre prospective cohort.SettingThirty-six midwifery practices and six hospitals (in the Netherlands).PopulationPregnant women were recruited atMethodsPrediction models were systematically selected from the literature. Information on predictors was obtained by a web-based questionnaire. Birthweight centiles were corrected for gestational age, parity, fetal sex, and ethnicity.Main outcome measuresPredictive performance was assessed by means of discrimination (C-statistic) and calibration.ResultsThe validation cohort consisted of 2582 pregnant women. The outcomes of SGA 90th percentile occurred in 203 and 224 women, respectively. The C-statistics of the included models ranged from 0.52 to 0.64 for SGA (n=6), and from 0.60 to 0.69 for LGA (n=6). All models yielded higher C-statistics for more severe cases of SGA (95th percentile). Initial calibration showed poor-to-moderate agreement between the predicted probabilities and the observed outcomes, but this improved substantially after recalibration.ConclusionThe clinical relevance of the models is limited because of their moderate predictive performance, and because the definitions of SGA and LGA do not exclude constitutionally small or large infants. As most clinically relevant fetal growth deviations are related to vascular' or metabolic' factors, models predicting hypertensive disorders and gestational diabetes are likely to be more specific.
AB - ObjectiveTo assess the external validity of all published first-trimester prediction models based on routinely collected maternal predictors for the risk of small- and large-for-gestational-age (SGA and LGA) infants. Furthermore, the clinical potential of the best-performing models was evaluated.DesignMulticentre prospective cohort.SettingThirty-six midwifery practices and six hospitals (in the Netherlands).PopulationPregnant women were recruited atMethodsPrediction models were systematically selected from the literature. Information on predictors was obtained by a web-based questionnaire. Birthweight centiles were corrected for gestational age, parity, fetal sex, and ethnicity.Main outcome measuresPredictive performance was assessed by means of discrimination (C-statistic) and calibration.ResultsThe validation cohort consisted of 2582 pregnant women. The outcomes of SGA 90th percentile occurred in 203 and 224 women, respectively. The C-statistics of the included models ranged from 0.52 to 0.64 for SGA (n=6), and from 0.60 to 0.69 for LGA (n=6). All models yielded higher C-statistics for more severe cases of SGA (95th percentile). Initial calibration showed poor-to-moderate agreement between the predicted probabilities and the observed outcomes, but this improved substantially after recalibration.ConclusionThe clinical relevance of the models is limited because of their moderate predictive performance, and because the definitions of SGA and LGA do not exclude constitutionally small or large infants. As most clinically relevant fetal growth deviations are related to vascular' or metabolic' factors, models predicting hypertensive disorders and gestational diabetes are likely to be more specific.
KW - Decision curve analysis
KW - externsal validation
KW - fetal growth
KW - first trimester
KW - large for gestational age
KW - prediction
KW - risk assessment
KW - small for gestational age
KW - FETAL-GROWTH RESTRICTION
KW - INDEPENDENT RISK-FACTOR
KW - UTERINE ARTERY DOPPLER
KW - BIRTH-WEIGHT CENTILES
KW - MATERNAL SERUM
KW - PLACENTAL VOLUME
KW - PREECLAMPSIA
KW - MACROSOMIA
KW - MORBIDITY
KW - MORTALITY
U2 - 10.1111/1471-0528.15516
DO - 10.1111/1471-0528.15516
M3 - Article
C2 - 30358080
SN - 1470-0328
VL - 126
SP - 472
EP - 484
JO - Bjog-an International Journal of Obstetrics and Gynaecology
JF - Bjog-an International Journal of Obstetrics and Gynaecology
IS - 4
ER -