The aggregation of marginal gains: a pragmatic philosophy of clinical care in psychiatry

The cliched opening sentence of many articles in the psychiatric field bemoans the limited efficacy of individual treatments. However, this singular truth is far from the whole truth. The theory of aggregation of marginal gains, also known as the “1% improvement theory”, suggests that small, sustained, incremental improvements in multiple areas can lead to substantial overall progress in a given field1. This theory has been applied in various areas, including sports, business, and health care, and appears to be relevant to psychiatric clinical practice.