Health services have become archipelagos. There are great islands like primary care and secondary care, acute and community, or public health and clinical practice, and each one is surrounded by deep water with the occasional ferryboat or swimmer going between them.
Any tension between public health and clinical practice is artificial; a population perspective and a clinical perspective are views of two sides of the same coin. The best way to understand this is to think about value.
From a population perspective, the relationship between value and the amount of resources invested was wonderfully described by Avedis Donabedian in 1980. In his classic diagram (left), perhaps the most important picture in healthcare, he showed that benefits rose fast and then levelled out as investment increased—epitomising the law of diminishing returns. Harm rises in a straight line. Even when in the best hands, the more healthcare we do the more harm we do too, because we are carrying out procedures that have risks.
The work on overdiagnosis and overtreatment is highlighting interventions on the right hand side of this spectrum.
From an individual’s perspective, there is a slightly different type of relationship shown in the below figure (click image to enlarge). As we put more resources into a particular intervention or operation, the offer for the individual patient changes. When there is only enough resource to make interventions available to a few, they are offered to people who have the most to gain, and who are therefore more willing to accept a risk. However, as investment increases, interventions are offered to people who are less severely affected; therefore the maximum benefit they can expect is less, but both the probability and the magnitude of harm is the same.
Population healthcare and personalised care are two sides of the same coin. It’s sometimes a different language, but it’s the same currency.
Muir Gray is the director of Better Value Healthcare (bvhc) and a partner in the Oxford Academic Health Science Network.