title: A review of sonographic estimate of fetal weight: vagaries of accuracy.
abstract: OBJECTIVE
  To determine the factors that might influence the accuracy of sonographic estimated fetal weight.
  
  
  METHODS
  A PubMed search (Jan 1975 to Jan 2003) of articles published in the English language was carried out and the inclusion criterion was that estimates were within 10% of birth weight. A Chi-square test for trend was used and odds ratio (OR) with 95% confidence intervals (CI) was calculated.
  
  
  RESULTS
  Over 28 years, 175 articles were identified but only 54 (31%) met the inclusion criterion. Overall 62% (8895/14 384) of the predictions were within 10% of the actual weight. The accuracy was significantly different in articles where <7 vs. >7 days were allowed to lapse between examination and delivery (OR 2.17, 95% CI 1.93, 2.45); where examinations were done by registered diagnostic medical sonographers (RDMS; 65%) versus physicians (59%) or residents (57%; p < 0.0001); in term vs. preterm patients (OR 1.97, 95% CI 1.67, 2.13); and in studies with >1000 vs. <1000 cohorts (OR 1.62; 95% CI 1.51, 1.74).
  
  
  CONCLUSIONS
  If feasible the sonographic examination should be done by RDMS and within a week of delivery.
authors.affiliation: Spartanburg Regional Medical Center, Spartanburg, SC 29303, USA. mfmchauhan@aol.com
authors.forename: Suneet P
authors.initials: SP
authors.lastname: Chauhan
authors.forename: Nancy W
authors.initials: NW
authors.lastname: Hendrix
authors.forename: Everett F
authors.initials: EF
authors.lastname: Magann
authors.forename: John C
authors.initials: JC
authors.lastname: Morrison
authors.forename: James A
authors.initials: JA
authors.lastname: Scardo
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Berghella
mesh_terms: D001724:Birth Weight; D002983:Clinical Competence; D005260:Female; D020567:Fetal Weight; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D047928:Premature Birth; D012107:Research Design; D013997:Time Factors; D016216:Ultrasonography, Prenatal / Q000379:methods*