This report has now been published as an article in Value in Health available here.

The NHS is facing unprecedented health system pressure, with a record number of patients waiting for care, while their underlying condition is potentially worsening due to exceptionally long waits.

When there is excess demand for health care, treating one patient means losing the opportunity to treat another. These opportunity costs demonstrate the need to consider health system capacity value, one of the so-called “broader value elements” that is often not fully captured in traditional value assessments.

Vaccinations against potentially severe diseases can prevent hospitalisations. For each hospital admission prevented, vaccination accrues direct savings to the health system by not having to treat that patient and avoids the opportunity cost of not being able to use the hospital bed for another patient. In “normal times” where hospital capacity is typically available (or can be expected to free up within a relatively short time), that opportunity cost is zero. Hence this is not usually considered in value assessment. When there are waiting lists, however, it is positive and potentially large.

This report shows that the opportunity cost saved through vaccination rises with increasing levels of excess demand for treatment and the increasing share of patients whose conditions become more severe due to a treatment delay.

Using a novel approach, we estimate that the opportunity costs saved by four selected vaccination programmes are about twice the direct savings from prevented hospitalisations. Hence, vaccinations may be substantially undervalued when their broader health system capacity value is not fully accounted for.

This approach is important for policymakers and relevant for any health technology that significantly reduces or prevents the need for healthcare resources across various care sectors and for which today’s demand already exceeds the relevant capacity.