title: A prospective study to assess the clinical impact of interobserver reliability of sonographic measurements of fetal nuchal translucency and crown-rump length on combined first-trimester screening.
abstract: OBJECTIVE
  To examine the interobserver variability for fetal biometric parameters and to focus on how this variability affects the combined first-trimester screening test results.
  
  
  METHODS
  Sixty-four singleton pregnancies who were scheduled for combined first-trimester screening were investigated. Two experienced sonographers performed all examinations at the same visit. The risk calculations of screening were performed according to the each operator's individual ultrasonographic fetal measurements. Interobserver variability in measurements of fetal nuchal translucency (NT) and crown-rump length (CRL) and the effect of this interobserver variability on the screening results were assessed.
  
  
  RESULTS
  Interobserver reliabilities for NT and CRL were 0.687 and 0.945 (p<0.001), respectively. Interobserver reliability coefficients for trisomy 21 and trisomy 13/18 were 0.945 and 0.963 (p<0.001), respectively.
  
  
  CONCLUSIONS
  Our study demonstrated quite high interobserver reliability for CRL measurement, while interobserver agreement for NT was lower. Despite this lower reliability and agreement for NT measurement, interobserver reliability for chromosomal abnormalities was quite high.
authors.affiliation: Department of Obstetrics and Gynecology, Kayseri Military Hospital, Kayseri, Turkey.
authors.forename: Huseyin
authors.initials: H
authors.lastname: Aksoy
authors.affiliation: Department of Obstetrics and Gynecology, Kayseri Training and Research Hospital, Kayseri, Turkey.
authors.forename: Sezin
authors.initials: S
authors.lastname: Ozyurt
authors.affiliation: Department of Obstetrics and Gynecology, Kayseri Memorial Hospital, Kayseri, Turkey.
authors.forename: Ulku
authors.initials: U
authors.lastname: Aksoy
authors.affiliation: Department of Obstetrics and Gynecology, Corlu Military Hospital, Tekirdag, Turkey.
authors.forename: Erol
authors.initials: E
authors.lastname: Mutlu
authors.affiliation: Department of Radiology, Kayseri Training and Research Hospital, Kayseri, Turkey.
authors.forename: Sadan
authors.initials: S
authors.lastname: Tutus
authors.affiliation: Department of Public Health and Epidemiology, Gulhane Military Faculty of Medicine, Ankara, Turkey.
authors.forename: Mustafa Alparslan
authors.initials: MA
authors.lastname: Babayigit
authors.affiliation: Department of Obstetrics and Gynecology, Kayseri Training and Research Hospital, Kayseri, Turkey.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Acmaz
authors.affiliation: Department of Obstetrics and Gynecology, Kayseri Acibadem Hospital, Kayseri, Turkey.
authors.forename: Ozge Idem
authors.initials: OI
authors.lastname: Karadag
authors.affiliation: Department of Obstetrics and Gynecology, Kayseri Acibadem Hospital, Kayseri, Turkey.
authors.forename: Burak
authors.initials: B
authors.lastname: Yucel
keywords: First-trimester screening; interobserver reliability; nuchal translucency; trisomy 21