目的:将严重先天性畸形的研究限制在活产儿童中,可能会导致严重的偏倚。在这项研究中,我们估计了妊娠中期胎儿畸形筛查计划的出勤率.我们还估计了丹麦国家患者登记处(DNPR)中记录的产前分配的国际疾病10分类诊断的阳性预测值(PPV)以及病例登记的完整性。我们以肾脏异常为例。
方法:我们确定了2007年1月1日至2012年12月31日所有丹麦活产婴儿的比例,这些婴儿在孕中期使用DNPR和民事登记系统进行扫描。根据DNPR检索具有特定肾脏异常诊断的所有胎儿的详细信息。PPV是使用全国的Astrica怀孕医疗图表或传统医疗图表数据库估算的,作为黄金标准。使用通过捕获-重新捕获方法估计的病例总数来评估完整性。
结果:在372,263名活产婴儿中,在妊娠中期扫描了97.3%。我们在DNPR中鉴定了172个胎儿。其中,根据阿斯迪亚或医学图表审查,149人患有肾脏异常,对应于87%的PPV(95%CI:81%-91%)。DNPR的估计完整性为43%(95%CI:38%-49%),Agradia的估计完整性为75%(95%CI:70%-79%)。
结论:在丹麦,几乎所有的活产婴儿都在妊娠中期接受了扫描。然而,低完整性可能会阻碍DNPR用于产前检测到的严重畸形的研究,并且可以优选地考虑使用Agraya数据库。
OBJECTIVE: Restricting studies of severe congenital malformations to live-born children may introduce substantial bias. In this study, we estimated the attendance to the second-trimester fetal malformation screening program. We also estimated the positive predictive value (PPV) of prenatally assigned International Classification of Disease-10 diagnoses recorded in the Danish National Patient Registry (DNPR) and the completeness of case registration. We used kidney anomalies as an example.
METHODS: We identified the proportion of all Danish live-born children from January 1, 2007 to December 31, 2012, who were scanned during the second trimester using the DNPR and the Civil Registration System. Details of all fetuses with specific kidney anomaly diagnoses according to the DNPR were retrieved. The PPV was estimated using the nationwide Astraia database of pregnancy medical charts or traditional medical charts, as gold standard. The completeness was assessed using the total number of cases estimated by the capture-recapture method.
RESULTS: Of 372,263 live born infants, 97.3% were scanned during the second trimester. We identified 172 fetuses in the DNPR. Of these, 149 had kidney anomalies according to Astraia or medical chart review, corresponding to a PPV of 87% (95% CI: 81%-91%). The estimated completeness was 43% (95% CI: 38%-49%) for the DNPR and 75% (95% CI: 70%-79%) for Astraia.
CONCLUSIONS: Almost all live-born children were scanned during the second trimester in Denmark. However, low completeness may hamper the use of the DNPR for studies of prenatally detected severe malformations, and use of the Astraia database may preferably be considered.