Let us now define research through its characteristics. Research begins with a problem or a question followed by the setting of goals and devising of a method or specific plan. The main problem is expounded by a hypothesis and assumptions regarding the cause or possible solutions are accepted as part of the research process. Research is not only about data gathering, but it is likewise concerned with the interpretation of data as a means to arrive at a solution to the problem or an answer to the main question (Andersen).
There are four basic research design elements. These elements include treatments, measures, time and groups or individual. We shall focus on the time element for the purposes of this paper. Time is very important as it determines the degree and quality of observed changes. There are two classifications of research design under the time element: cross-sectional and longitudinal studies. A cross-sectional study is carried out at one instance, while a longitudinal study occurs over a period of time with a series of measurements (Trochim, 2006). A cross-sectional study includes observation of diverse groups of people of various age levels or a cross-section of a population. A longitudinal study involves observing and gathering information from the same group of people over a period of time.
The focus of cross-sectional studies is on the differences between groups at a certain point in time, while the focus of longitudinal studies is on individual change over an extended period of time (A Research Typology, 2004). Since a cross-sectional study is done at only one instance, the expenses and time needed to gather data are very minimal. This is an advantage of the cross-sectional strategy. It is more convenient for both the participants and the researcher because there is only one period for data gathering (King, 2001). The participants need not go back for other sessions and researchers do not need to maintain contact with participants and sustain a budget for data collection over a long period of time. Another advantage is the large amount of diverse data that can be collected at one time. This data is very useful to the researcher in the immediate analysis and solution of a problem, and may also be very helpful to other researchers searching for similar data. A major disadvantage though of this strategy is its failure to measure the actual individual changes that will occur or may inevitably be experienced by the subjects. It is a static representation of the variables and causes and effects cannot be measure accurately. In attitudinal or perception studies more often used in Psychology, a cross-sectional study is not dependable because many factors may affect the disposition or attitude of a person at a given time. Personal problems or emotionally disturbance experienced by subjects very close to the data gathering session may affect their responses. The elimination of outside factors can be done through a longitudinal study where subjects are contacted at different periods where their experiences and personal dispositions are varied.
The main advantage of a longitudinal study is its ability to determine actual changes and trends that happen over a vast interval of time because it documents information from each subject at specific age levels and records comparisons between subjects across different timelines. Patterns of changes and causes of