Author Question: Describe the procedures of the cross-sectional and longitudinal research methods. What are the uses ... (Read 99 times)

sarasara

  • Hero Member
  • *****
  • Posts: 521
Describe the procedures of the cross-sectional and longitudinal research methods. What are the uses and limitations of each of these methods?
 
  What will be an ideal response?

Question 2

Describe the difference between the statistical and clinical significance of research findings. Explain why it is important to make a distinction between statistical and clinical significance when interpreting research findings.
 
  What will be an ideal response?



jesse.fleming

  • Sr. Member
  • ****
  • Posts: 301
Answer to Question 1

For a cross-sectional design, researchers take a cross section of a population across the different age groups and compare them on some characteristic. For example, if they were trying to understand the development of alcohol abuse and dependence, they could take groups of adolescents at 12, 15, and 17 years of age and assess their beliefs about alcohol use. In cross-sectional designs, the participants in each age group are called cohorts. The members of each cohort are the same age at the same time and thus have all been exposed to similar experiences. Members of one cohort differ from members of other cohorts in age and in their exposure to cultural and historical experiences. Differences among cohorts in their opinions may be related to their respective cognitive and emotional development at these different ages and to their dissimilar experiences. This cohort effect, the confounding of age and experience, is a limitation of the cross-sectional design.
One question not answered by cross-sectional designs is how problems develop in individuals. Rather than looking at different groups of people of differing ages, researchers may follow one group over time and assess change in its members directly. The advantages of longitudinal designs are that they do not suffer from cohort effect problems, and they allow researchers to assess individual change. Imagine conducting a major longitudinal study: not only must the researcher persevere over months and years, but so must the people who participate in the study. They must remain willing to continue in the project, and the researcher must hope they will not move away or, worse, die. Longitudinal research is costly and time-consuming. Finally, longitudinal designs can suffer from a phenomenon similar to the cohort effect on cross-sectional designs. The cross-generational effect involves trying to generalize the findings to groups whose experiences are different from those of the study participants.

Answer to Question 2

In psychological research, statistical significance typically means that the probability of obtaining the observed effect by chance is small. When one obtains statistical difference, is it an important difference? The difficulty is in the distinction between statistical significance (a mathematical calculation about the difference between groups) and clinical significance (whether or not the difference was meaningful for those affected). Concern for the clinical significance of results has led researchers to develop statistical methods that address not just that groups are different but also how large these differences are, or effect size. Calculating the actual statistical measures involves fairly sophisticated procedures that take into account how much each treated and untreated person in a research study improves or worsens. In other words, instead of just looking at the results of the group as a whole, individual differences are considered as well.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

A serious new warning has been established for pregnant women against taking ACE inhibitors during pregnancy. In the study, the risk of major birth defects in children whose mothers took ACE inhibitors during the first trimester was nearly three times higher than in children whose mothers didn't take ACE inhibitors. Physicians can prescribe alternative medications for pregnant women who have symptoms of high blood pressure.

Did you know?

Children of people with alcoholism are more inclined to drink alcohol or use hard drugs. In fact, they are 400 times more likely to use hard drugs than those who do not have a family history of alcohol addiction.

Did you know?

Certain chemicals, after ingestion, can be converted by the body into cyanide. Most of these chemicals have been removed from the market, but some old nail polish remover, solvents, and plastics manufacturing solutions can contain these substances.

Did you know?

Glaucoma is a leading cause of blindness. As of yet, there is no cure. Everyone is at risk, and there may be no warning signs. It is six to eight times more common in African Americans than in whites. The best and most effective way to detect glaucoma is to receive a dilated eye examination.

Did you know?

Giardia is one of the most common intestinal parasites worldwide, and infects up to 20% of the world population, mostly in poorer countries with inadequate sanitation. Infections are most common in children, though chronic Giardia is more common in adults.

For a complete list of videos, visit our video library