The adjustment of cost measurement to account for learning

This note discusses the adjustment of cost measurement to account for learning. By learning is meant improvements in productive efficiency resulting from use of a (health) technology in routine practice. A recently proposed method is shown to be potentially misleading. Alternatively, it is suggested that the total cost is decomposed in treatment cost and learning cost. Furthermore, if there is uncertainty about the long-run unit cost, learning will reveal the true cost. A method to adjust the learning cost for the value of this information is illustrated.