The accuracy of self-reported pregnancy-related weight: a systematic review.
Self-reported maternal weight is error-prone, and the context of pregnancy may impact error distributions. This systematic review summarizes error in self-reported weight across pregnancy and assesses implications for bias in associations between pregnancy-related weight and birth outcomes. We searched PubMed and Google Scholar through November 2015 for peer-reviewed articles reporting accuracy of self-reported, pregnancy-related weight at four time points: prepregnancy, delivery, over gestation and postpartum. Included studies compared maternal self-report to anthropometric measurement or medical report of weights. Sixty-two studies met inclusion criteria. We extracted data on magnitude of error and misclassification. We assessed impact of reporting error on bias in associations between pregnancy-related weight and birth outcomes. Women underreported prepregnancy (PPW: -2.94 to -0.29 kg) and delivery weight (DW: -1.28 to 0.07 kg), and over-reported gestational weight gain (GWG: 0.33 to 3 kg). Magnitude of error was small, ranged widely, and varied by prepregnancy weight class and race/ethnicity. Misclassification was moderate (PPW: 0-48.3%; DW: 39.0-49.0%; GWG: 16.7-59.1%), and overestimated some estimates of population prevalence. However, reporting error did not largely bias associations between pregnancy-related weight and birth outcomes. Although measured weight is preferable, self-report is a cost-effective and practical measurement approach. Future researchers should develop bias correction techniques for self-reported pregnancy-related weight.
Division of Community Health Science, University of California Berkeley, School of Public Health, Berkeley, CA, USA.
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I
Headen
Division of Epidemiology, University of California Berkeley, School of Public Health, Berkeley, CA, USA.
A K
AK
Cohen
Division of Epidemiology, University of California Berkeley, School of Public Health, Berkeley, CA, USA.
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M
Mujahid
Division of Epidemiology, University of California Berkeley, School of Public Health, Berkeley, CA, USA.
B
B
Abrams
D015992:Body Mass Index; D036262:Empirical Research; D005260:Female; D006801:Humans; D064887:Observational Studies as Topic; D011247:Pregnancy; D015203:Reproducibility of Results; D057566:Self Report; D015430:Weight Gain
Postpartum period; pregnancy; validity; weight