Identification of heart failure subtypes within patient records:An analysis of linked primary and secondary care data in England

Chronic heart failure (HF) is generally well-recorded in primary care in England, but whether data can identify subtypes such as heart failure with reduced (HFrEF) or preserved (HFpEF) ejection fraction in this setting is unclear. Using data from English general practices and secondary care admissions, we investigated how well HFrEF and HFpEF were recorded for patients with diagnosed HF and described patient characteristics by subtype to investigate possible recording bias