OBJECTIVES: Identification of patients with overweight and obesity in claims databases relies on the presence of diagnosis codes. The objective of this study is to describe the agreement between claims and electronic medical record (EMR) databases to evaluate the validity of overweight and obese body mass index (BMI) diagnoses in claims.

METHODS: Adults with a claim indicating BMI between 1/1/2016-12/31/2021 were identified in the MarketScan Claims and EMR Database (CED). Date of the first medical claim for BMI was the index date and patients were required to have one valid BMI recorded in the EMR within 30 days of the index date. Patients with more than one BMI in the EMR within 30 days of the index date were excluded (<5%). Four cohorts were created based on EMR BMI: underweight (<19 kg/m²), normal weight (19-<25 kg/m²), overweight (25-<30 kg/m²), and obese (≥30 kg/m²). The number of patients with the same BMI category in claims and EMR were identified and the percent positive agreement (PPA) was calculated within each EMR BMI category to describe the agreement between claims and EMR.

RESULTS: 124,541 patients had a medical claim for BMI and one BMI measurement in the EMR within 30 days and were included in the analysis. About two-thirds had obese BMI (64%), 22% had overweight BMI, 13% had normal weight BMI, and 3% had underweight BMI. PPA between claims and EMR databases was highest in the patients with obese BMI (98%) and overweight BMI (88%) though PPA was also high in patients with normal weight and underweight BMI (79% for both).

CONCLUSIONS: Diagnosis codes indicating BMI on medical claims can be reliably used to identify patients with overweight and obesity. However, BMI reporting in both the claims and EMR data was low overall and differential across BMI categories, with obese and overweight BMI most frequently reported.