An-Najah National University Faculty of Nursing Cross-sectional Designs

1. An-Najah National University Faculty of Nursing Cross-sectional Designs Prepareby : اشرف ذيب رائد حبايبة Prepared to : Dr Aidah Abu Elsoud Alkaissi

2. Definition • Cross-Sectional Designs:(also known as Cross-sectional analysis) form a class of research methods that involve the collection of data at one point in time.

3. Cross-sectional studies are appropriate for describing the status of phenomena or for describing relationships among phenomena at a fixed point in time.

4. For example, we might be interested in determining whether psychological symptoms in menopausal women are correlated contemporaneously with physiologic symptoms.

5. They are often used to assess theprevalence of acute or chronic conditions, or to answer questions about the causes of disease or the results of medical intervention.

6. The main advantage of cross-sectional designs: • they are easy to do. • fast and can study a large number of patients at little cost or effort.

7. Cross-sectional data can most appropriatelybe used to infer time sequence undertwo circumstances: • (1) when there is evidence orlogical reasoning indicating that one variable precededthe other (e.g., in a study of the effects of lowbirth weight on morbidity in school-aged children,there would be no confusion over whether birthweight came first); • (2) when a strong theoreticalframework guides the analysis

8. Cross-sectional studies can also be designed to permit inferences about processes evolving over time, such as when measurements capture a process at different points in its evolution with different people. • As an example, suppose we wanted to study changes in professionalism as nursing students progress through a 4-year baccalaureate program.

9. One way to investigate this would be to gather data from students every year until they graduate; this would be a longitudinal design.

10. On the other hand, we could use a cross-sectional design by gathering data at a single point from members of the four classes, and then comparing the responses of the four classes. If seniors had higher scores on a measure of professionalism than freshmen, it might be inferred that nursing students become increasingly socialized professionally by their educational experiences.

11. Example of a cross-sectional study: • Mindell and Jacobson (2000) assessed sleep patterns and the prevalence of sleepdisorders duringpregnancy. With a cross-sectional design, theycompared women who were at four points in pregnancy:8 to 12 weeks, 18 to 22 weeks; 25 to 28weeks; and 35 to 38 weeks. They concluded that sleep disturbances were especially common in late pregnancy.