M1A1 : Research and Design Methodology 2

In order to understand human development one must observe how people change over time at different ages. In the logitudinal design participants or groups are studied over and over again at differetn times and chages are noted as they age. The observation time can very depending on information being gathered. Sometimes lasting short periods of time or years. One benefit of the logitudinal approach is that it would observe each persons performances over the specified time span, allowing to identify any patters or problems in development. Another benefit is that it allows participants to be studied at different ages. Some problems with the longitudinal approach are cohort effects, participants moving or dropping out of the study and participants change to a population that is no longer part of the study, often happening from becoming familiar with test questions and stradigies.

In the cross-sectional design people are studied at different ages at the same time. For example if all of the patients at an orthopedic office were interviewed about diet and exercise, all patients were between the ages of two and sixty-four. As a result the practice could then develop a proactive approach to patient education and preventing future injuries that might be prevelant in certain age-related trends. There are problems with this sort of study as well. In the example above different results are limited to age group averages. It is difficult to tell if individual differences are present. It might also be difficult to have comparison with people that were born into different generations. While it might be important for a forty year old to maintain an active lifestyle while using proper body mechanics to avoid injury, someone in their teens may be more interested