What is a disadvantage of conducting longitudinal studies?

Conducting longitudinal studies involves tracking the same individuals over an extended period, which allows for the observation of development and changes over time. However, one of the notable disadvantages is the costly nature of such studies and the potential for dropouts. Longitudinal studies generally require substantial financial resources due to the need for long-term funding, data collection, and repeated assessments over time.

Additionally, participant retention can be a significant challenge. Over the course of a study that spans many years, factors such as personal circumstances, relocation, or loss of interest can result in participants dropping out. This attrition can lead to biases in the data, as those who remain may not be representative of the initial cohort.

In contrast, other study designs like cross-sectional studies, which compare different age groups at a single point in time, do not face these long-term financial and retention challenges. Therefore, the costly nature and potential for dropouts highlight why this is a critical disadvantage of longitudinal studies.