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Reducing misclassification in assignment of timing of events during pregnancy.

Publication ,  Journal Article
Yang, J; Hartmann, KE; Herring, AH; Savitz, DA
Published in: Epidemiology (Cambridge, Mass.)
January 2005

Perinatal epidemiology studies often collect only the calendar month in which an event occurs in early pregnancy because it is difficult for women to recall a specific day when queried later in pregnancy or postpartum. Lack of day information may result in incorrect assignment of completed gestational month because calendar months and pregnancy months are not aligned.To examine the direction and magnitude of misclassification, we compared 3 methods for assignment of completed gestational month: 1) calendar month difference, 2) conditional month difference, and 3) imputed month midpoint. We used data from the Pregnancy, Infection, and Nutrition Study for simulations.Calendar month difference misclassified 54% of events as 1 month later in pregnancy compared with the actual completed month of gestation. Each of the other 2 methods misclassified approximately 12% of events to 1 month earlier and 12% to 1 month later.Calendar month difference, a common method, has the greatest misclassification. Conditional month difference and imputed month midpoint, which require little effort to implement, are superior to calendar month difference for reducing misclassification.

Duke Scholars

Published In

Epidemiology (Cambridge, Mass.)

DOI

EISSN

1531-5487

ISSN

1044-3983

Publication Date

January 2005

Volume

16

Issue

1

Start / End Page

121 / 123

Related Subject Headings

  • Time Factors
  • Surveys and Questionnaires
  • Surrogate Mothers
  • Prospective Studies
  • Pregnancy
  • Postpartum Period
  • North Carolina
  • Humans
  • Gestational Age
  • Female
 

Citation

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Chicago
ICMJE
MLA
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Yang, J., Hartmann, K. E., Herring, A. H., & Savitz, D. A. (2005). Reducing misclassification in assignment of timing of events during pregnancy. Epidemiology (Cambridge, Mass.), 16(1), 121–123. https://doi.org/10.1097/01.ede.0000147120.50700.06
Yang, Juan, Katherine E. Hartmann, Amy H. Herring, and David A. Savitz. “Reducing misclassification in assignment of timing of events during pregnancy.Epidemiology (Cambridge, Mass.) 16, no. 1 (January 2005): 121–23. https://doi.org/10.1097/01.ede.0000147120.50700.06.
Yang J, Hartmann KE, Herring AH, Savitz DA. Reducing misclassification in assignment of timing of events during pregnancy. Epidemiology (Cambridge, Mass). 2005 Jan;16(1):121–3.
Yang, Juan, et al. “Reducing misclassification in assignment of timing of events during pregnancy.Epidemiology (Cambridge, Mass.), vol. 16, no. 1, Jan. 2005, pp. 121–23. Epmc, doi:10.1097/01.ede.0000147120.50700.06.
Yang J, Hartmann KE, Herring AH, Savitz DA. Reducing misclassification in assignment of timing of events during pregnancy. Epidemiology (Cambridge, Mass). 2005 Jan;16(1):121–123.

Published In

Epidemiology (Cambridge, Mass.)

DOI

EISSN

1531-5487

ISSN

1044-3983

Publication Date

January 2005

Volume

16

Issue

1

Start / End Page

121 / 123

Related Subject Headings

  • Time Factors
  • Surveys and Questionnaires
  • Surrogate Mothers
  • Prospective Studies
  • Pregnancy
  • Postpartum Period
  • North Carolina
  • Humans
  • Gestational Age
  • Female