Aymerich M, Almazan C, Estrada D, Sanchez E, Mias M; International Society of Technology Assessment in Health Care. Meeting.
Annu Meet Int Soc Technol Assess Health Care Int Soc Technol Assess Health Care Meet. 2002; 18: abstract no. 18.
Catalan Agency for Health Technology Assessment and Research, CAHTA, Travessera de les Corts, 131-159 08028 Barcelona, maymeric@olimpia.scs.es; calmazan@olimpia.scs.es; destrada@ olimpia.scs.es; emsanche@olimpia.scs.es; diraatm@olimpia.scs.es
BACKGROUND/OBJECTIVES: To compare systematic reviews and meta-analyses compiling medical research, with recommendations and guidelines specifically designed for clinical practice. The ultrasound imaging for routine prenatal care was selected as case study. METHODS: A meta-analysis of nuchal fold thickness as a second trimester marker for Down syndrome was car ried out. The studies to be included were identified through several bibliographic search strategies and se-lected according to a minimal set of quality criteria. Overall pooled sensitivity and specificity values were estimated by a random effects model. In addition, systematic reviews and also clinical practice guidelines (CPG) for routine ultrasound in pregnancy were searched through specific databases. RESULTS: Twenty-six studies were identified that met the quality criteria for inclusion in the meta-analysis. The overall diagnostic accuracy of thickened nuchal fold as a marker for Down syndrome showed a sensitivity value of 33% (95% CI: 26% - 41%), and a specificity value of 99% (95% CI: 99% - 100%). Additionally, two comprehensive systematic reviews were found which concluded that routine ultrasound provides better gestational age assessment and earlier detection of multiple pregnancies, but neither of these effects has been shown to improve fetal outcome. Regarding CPG for routine ultrasound imaging in prenatal care, some of them recommend three scans during pregnancy, some others only one carried out at the 2nd trimester, and some recommend no routine ultrasound examinations. Therefore, after comparing these CPG to previous sys-tematic reviews, scientific evidence and routine ultrasonography recommendations were found not to agree in each and all cases. DISCUSSION: The nuchal fold thickness is very specific but not very sensitive to detect Down fetuses. Despite this low sensitivity it is common practice among obstetricians to routinely scan for the thickened nuchal fold as a marker for Down syndrome. This gap between medical literature and clinical practice can be also seen comparing systematic reviews and CPG regarding routine prenatal ultrasound examinations. This illustrates either a delay translating the obstetric ultrasound research findings into clinical practice, or a lack of research showing the effects of performing ultrasound scans in routine prenatal care. .
Publication Types:
Keywords:
- Biological Markers
- Down Syndrome
- Female
- Fetus
- GTPase-Activating Proteins
- Gestational Age
- Maternal Age
- Meta-Analysis
- Pregnancy
- Pregnancy Trimester, First
- Pregnancy Trimester, Second
- Pregnancy Trimester, Third
- Pregnancy, High-Risk
- Pregnancy-Associated Plasma Protein-A
- Prenatal Care
- Prenatal Diagnosis
- Sensitivity and Specificity
- hsrmtgs
Other ID:
UI: 102274634
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