Perpatient

Perpatient is a term used in healthcare analytics to express metrics on a per-patient basis. It denotes normalization by the number of patients in a population or cohort and is distinct from measures based on encounters, episodes, or populations. The term is not universally standardized, but it appears in research reports and dashboards to emphasize patient-level denominators.

Calculation of perpatient metrics involves dividing a total value by the number of patients in the defined cohort. For example, perpatient cost equals total costs for the cohort divided by the number of patients. Denominators can vary: the metric may refer to all enrolled patients in a time frame, patients treated within the period, or patients diagnosed with a specific condition. Clear specification of the denominator is essential for correct interpretation and valid comparisons.

Perpatient measures are used to describe average outcomes, costs, or utilization per patient. They support comparisons across patient groups, facilities, or time periods where patient units are the natural basis for analysis. Examples include costs per patient, adverse events per patient, or readmissions per patient.

Limitations and considerations include the aggregation of patient-level variation, which can obscure heterogeneity in care needs or outcomes. Differences in follow-up duration, data completeness, and inclusion criteria can bias perpatient results. When comparing across settings, consistent definitions of the patient population and careful handling of censored data are important.

See also: per-encounter, per-capita, patient-level metrics, healthcare analytics.