Final answer:
Longitudinal research involves studying the same group of individuals over an extended period of time to understand changes and development. It provides accurate information about changes over time and can help identify causal relationships, but is time-consuming and costly with high attrition rates.
Step-by-step explanation:
Longitudinal research is a research design in which data-gathering is administered repeatedly over an extended period of time. It involves studying the same group of individuals over time, often to understand how they change or develop. For example, a researcher may survey a group of individuals about their dietary habits at age 20, retest them at age 30, and then again at age 40. This approach allows researchers to track changes and identify patterns over time.
Some strengths of longitudinal research are that it allows for the study of individual development, provides more accurate information about changes over time, and can help identify causal relationships. However, longitudinal research also has limitations, such as the need for a significant time and financial investment, high attrition rates, and potential biases due to participant dropout.