[Efficiency of Prenatal Ultrasound Screening Service in Beijing: A Malmquist-Data Envelopment Analysis].

Objective To analyze the efficiency of prenatal ultrasound screening service in Beijing and thus optimize the secondary prevention system for birth defects in Beijing. Methods Data were collected from the prenatal screening work reports of Beijing from 2010-2016.Key variables were extracted after data quality control.Data envelopment analysis was performed to analyze the efficiency and changing trend of ultrasound-based screening service and to...