This is a summary of the Longitudinal Cohort Studies section of GREO's Conceptual Framework of Harmful Gambling. Longitudinal cohort studies are studies that follow and observe a cohort of people over a period of time. A cohort is a group of people who share some characteristics. For example, they might have been exposed to an increase in gambling opportunities due to new policies. Longitudinal studies may last for many years. There are two main types of longitudinal cohort studies. In retrospective studies, researchers use data that have already been gathered. While retrospective studies tend to be less costly, the research may be limited by the kind of data that is available. Prospective studies are planned in advance to observe a cohort over a long period.
Longitudinal studies allow researchers to link the risk factors of a health condition (e.g., gambling) to the consequences over time. There have been prospective cohort studies examining gambling and problem gambling since the 1990s. However, early studies had a number of limitations. Those studies involved a small number of participants, with many dropping out of the study before it ended. They tended to follow the participants over a short period and consider only a subset of possible risk factors. The limitations of early studies led to the launch of a few large-scale longitudinal studies, as described in more detail in this summary.
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