On Friday 3 July 2020, A. Gini will defend his PhD dissertation, entitled: ‘Microsimulation Models to Inform Colorectal Cancer Screening Decisions: From validated tools to tailoring recommendations’.
Colorectal cancer (CRC) is a major health problem. Globally, 1.8 million new cases and 881,000 deaths are estimated every year. The main risk factors for CRC are low physical activity, smoking, obesity, diabetes, red meat, processed meat, and alcohol consumption. Those factors can be considered as indicators of the Western diet/lifestyle and are more prevalent in high developed countries. CRC incidence rates increase also with age, especially above age 50 years. At young age, CRC is very rare and mainly caused by specific hereditary disorders such as familial adenomatous polyposis and hereditary non-polyposis CRC (Lynch Syndrome). Furthermore, recent studies have shown also that individuals with Cystic Fibrosis (CF) and Childhood Cancer Survivors (CCS) are at high risk of developing CRC at young age (<50 years).
The burden of CRC can be reduced with CRC screening. Although CRC screening has been recommended by several health organizations and medical associations worldwide, it has not been implemented homogenously across countries. There are two main ways to provide CRC screening at population level: via opportunistic screening or via organized screening. In Europe, existing organized programs differ in terms of target ages, screening interval, and primary tests. In contrast, screening is mainly opportunistic in US and individuals are free to choose between screening tests. Several countries are facing organizational and financial barriers that limit the uptake of their CRC screening programme and its beneficial impacts. Decision-making in the field of CRC screening is complex with many parameters that can influence the effectiveness of a screening programme. Using microsimulation models can be useful for quantifying future outcomes and costs of screening, planning resources and identifying optimal policies to reduce CRC incidence and mortality. However, many of the current models are proprietary, limiting the capacity of policymakers to freely inform their decisions using models.
In the first part of this thesis, four studies were reported to describe the steps that are required to standardize the structure of a microsimulation model and make it the core of an online, open, and user-friendly model application (for European policymakers). These steps included: i) assessing effectiveness of CRC screening in different screening settings; ii) validating the model structure and its assumptions; and iii) building an online user-friendly platform that allow users to easily upload country-specific data, adjust a model, and simulate future outcomes of CRC screening in their countries.
The PhD defences will not take place publicly in the Senate Hall or Professor Andries Queridoroom due to the coronavirus. The candidates will defend their thesis online.