HTA responses and the classic HTA report.

Reports produced in response to the need for health technology assessment (HTA) vary greatly in the methods they use, depending on the decision-maker's needs, the technology's characteristics and the resources available. HTA reports vary from the brief, such as 'vignettes' produced when a new technology emerges, to the exhaustive, such as 'Cochrane reviews' synthesising a mature evidence base. They may address a wide range of different questions. 'Classic HTAs', typically those reports prepared to support NICE appraisal decisions, seek to use scientifically rigorous methods to address a focused policy question. These are based on systematic reviews of the effectiveness evidence but this is often fed into economic models, in order to generate estimates of cost-effectiveness. Future developments in HTA responses will reflect both the embedding of systematic methods and a growing responsiveness to customer needs.