The Weighted Activity Unit (WAU) is a 'common currency' to describe an amount of clinical activity, with a weighting applied that takes account of casemix and complexity.
This video explains how we use WAUs in the Model Hospital.
A WAU is quantity of any types of clinical activity including inpatients, outpatients, diagnostic testing and others. We take the national average cost of each clinical activity, and divide it by 3,500 to say how many WAUs that clinical activity is ‘worth’. The national average cost of a procedure comes from PLICs (which replaced reference costs in WAU calculations from 2018/19). One WAU equates to £3,500 ‘worth’ of healthcare services.