Study Type of data Exposure measurement Outcome assessment Adjustment
Choi a, 2023 retrospective cohort (claims database) Prescription database. The presence of congenital malformations was identified via infants’ records and major malformations and their subtypes were defined based on the European Surveillance of Congenital Anomalies (EUROCAT) classification system (minor defects were excluded according to the EUROCAT exclusion list). Propensity score: maternal age, income level, parity, multiple gestations, indications for PPIs (GERD, duodenitis...), maternal conditions (eg, anxiety, diabetes, and epilepsy), medication use (eg, opioid, NSAIDs), obstetric comorbidity index, and measures of health care use. Exclusion of exposures with known or potential teratogens. Sensitivity analyses: indications, singleton only, BMI, smoking.
Choi b, 2023 retrospective cohort (claims database) Prescription database. The National Health Insurance Service (NHIS) database. Propensity score: maternal age, medical aid, income level, parity, multiple gestations, indications for PPIs (GERD, duodenitis...), maternal conditions (eg, anxiety, diabetes, and epilepsy), other medication prescription, obstetric comorbidity index, and measures of health care use. Sensitivity analyses: indications, singleton only, body mass index, smoking, sibling design, first-time pregnancy.
Cluver, 2018 randomized controlled trial Randomized controlled trial with appropriate exposition. Plasma samples were collected to measures circulation preeclampsia and angiogenic biomarkers twice weekly until delivery. Placental tissue and umbilical artery cord blood were collected at delivery when possible. And surveillance of the other outcome. Gestational age strata and treatment group. Randomisation.
Pasternak, 2010 population based cohort retrospective The Prescription Drug Register provided information on all esomeprazole prescriptions filled by women in the cohort between 4 weeks before conception and delivery. Cases of birth defects were identified with the use of the National Patient Register and a random sample had a medical records review. Major birth defects were defined according to the EUROCAT classification. No potential confounder stood out as an important one, therefore, as an alternative all potential confounders and their effect were sum up into one variable: the propensity score.

master protocol