Fig. 1
Flowchart of the Cohort Selection. Abbreviations: DRG = diagnosis-related group; PTB = preterm birth; PTL = preterm labour; OPS = Operationen- und Prozedurenschlüssel
Fig. 1 | BMC Pregnancy and Childbirth
Flowchart of the Cohort Selection. Abbreviations: DRG = diagnosis-related group; PTB = preterm birth; PTL = preterm labour; OPS = Operationen- und Prozedurenschlüssel