Comparison of Lactation Information from Electronic Health Records with Survey Data Across Five US Health Systems

Data on lactation status for research are often collected through surveys. Information on human milk feeding collected at routine healthcare visits and stored in electronic health records (EHR) is an emerging source of data for lactation research. We compared information on milk feeding obtained from structured EHR fields with survey data.

We included participants from five US healthcare systems in the Managing Our Mood survey. Individuals had a live birth (March 2022-October 2023), depression diagnosis during pregnancy, and ≥1 record of human milk feeding information in their or their infant's EHR. We compared information from EHR data up to ten months after delivery with survey data collected 3-4 months after delivery as the reference. We assessed agreement on lactation status (human milk feeding ever and at survey) using percent agreement, Cohen's kappa, sensitivity, specificity, positive predictive value, and negative predictive value overall and by characteristics.

According to survey data, the prevalence of human milk feeding ever was 93.2% and was 73.0% at the time of survey among 281 eligible individuals. Agreement between data sources for ever and for human milk feeding at the survey was ≥92% with kappas ≥0.77. EHR and survey data agreed on human milk feeding ever for 97.3% (95% confidence interval: 94.6%, 98.7%) and on human milk feeding at the time of the survey for 98.0% (95% confidence interval: 95.1%, 99.2%) of those who reported yes to these practices on the survey. These measurements were lower among individuals with fewer records.

There was substantial agreement on lactation status between EHR and survey data. These findings suggest that lactation information from structured EHR may be used for epidemiologic research.