PURPOSE: The use of RCT data comparing survival between competing interventions is common for health economic evaluation models. In many cases the intervention affects these outcomes over a longer period than the RCT follow-up time. Estimates of expected survival beyond follow-up are often necessary for the economic evaluation of the alternative interventions. In this case parametric models are typically used to extrapolate the observed trends for each treatment arm. This approach is valid under the (practically untestable) assumption that the RCT hazard trends continue into the unobserved period. Given that the impact of this assumption can be substantial on the results of the economic evaluation, a reliably estimated complete survival curve is important and can be achieved only if long-term data are available. The objective of this workshop is to present various methods for the inclusion of long-term data from sources other than the RCTs, that can be used to estimate parameters of times to other events outcomes for health economic models. Participants will gain a broad overview of important methods, their strengths and limitations, and engage in a case study demonstrating the practical applications of these methods. DESCRIPTION: Starting from the limitations of the standard extrapolation approaches, Dr.Shaples and Dr.Demiris will present various methods for the inclusion of long-term data from sources like disease registries, general population data, cohort studies and formally elicited expert beliefs. They will also discuss the value of flexible parametric model (e.g poly-Weibull) for the extrapolation survival. Assumptions, strengths, limitations and acceptability by HTA authorities will be highlighted. Dr.Sagkriotis and Dr.Karabis will present an illustrative example, including technical challenges, practical obstacles in the process of obtaining the long-term data, cleaning, analyzing and interpreting the results. Participants will be encouraged to provide feedback at each step of the presentation (show of hands and questions).