A Beginners Guide to Cross Sectional Study
A cross-sectional study is a form of research that involves the collection of data from a population of different individuals at a particular point in time. In such research, the participants are selected on the basis of certain variables of interest. Also, you need to observe variables without making any changes, modifications, or influence on them.
As you can already guess, cross-sectional research is observational in nature. Researchers in the fields of psychology, economics, medicine, epidemiology, and other areas of social sciences use cross-sectional studies for their work. Such studies are also known as descriptive research. However, you cannot use it to determine the cause of something.
How to Define a Cross-sectional Study?
According to NCBI, a cross-sectional study can be defined as an observational study where the researcher examines the outcome and the exposures in the participants of the study at the same time. Such research designs are used for population-based surveys and to evaluate the prevalence of diseases in clinic-based samples. Such studies can be conducted relatively faster and are quite inexpensive.
Some key characteristics of a cross-sectional study are:
- It takes place at a definite point in time.
- It does not manipulate the variables.
- It lets the investigator look at various characteristics (such as age, gender, income, etc.) at once.
- It is used to observe the prevailing characteristics in a given population.
- The study can offer data about what is happening in the current population.
Instead of observing a group of people over an extended period of time, which happens in longitudinal studies, cross-sectional studies are performed to describe what is going on with the population at the present moment.
Cross-sectional Study Designs
Unlike in case-control studies, where the participants are chosen outcome status, the participants in cross-sectional research are selected simply on the basis of inclusion and exclusion criteria set of the particular study. Once the participants have been chosen for the research, the researcher follows the study to evaluate the exposure and the outcomes.
At the beginning of the study, the participants are measured for outcome and exposure at the same time. The researcher can study the link between these variables. The researcher may also recruit the participants in the study and assess the outcomes in this population. The researcher may also estimate the prevalence of the outcome in those surveyed participants.
Advantages of Cross-sectional Studies
There are several benefits of a cross-sectional study that make this form of research a popular choice across various fields. Some of the major advantages of this study include the following:
- Inexpensive and fast:
Cross-sectional methods usually allow the researchers to gather an adequate amount of data in a shorter time span. Also, data collection is conducted quite inexpensively, using self-report surveys. Researchers can collect a huge amount of data from a large number of participants.
- Multiple variables:
This form of study allows researchers to gather information on several different variables to observe how differences in age, sex, income, and educational status can correlate with the critical variable of interest.
- Paves the way for further study:
It is true that cross-sectional studies cannot help determine causal relationships. However, they can lead the way to further research. Researchers can use a cross-sectional study to look for clues that will serve as a useful factor to guide further studies in the field.
These advantages of a cross-sectional study certainly make things a lot easier for the researchers.
Limitations of Cross-sectional Study
It is important to understand that no research method is flawless. While you can enjoy a number of benefits of a cross-sectional study, you are also likely to face a number of limitations while conducting this form to study. Some of the major challenges of this study are:
- Inability to differentiate cause and effect:
As mentioned, it is difficult to establish cause-and-effect relationships using this form of study. Since cross-sectional studies only represent a one-time measurement of both the alleged cause and effect, it is hard for the research to infer the relationship between them.
- Cohort differences:
In this kind of study, groups are likely to be affected by cohort differences that arise from certain experiences of a unique group of people. For example, people of the same age may share the experience of similar events, but the people in the same group who are born in a different region of the world may share experiences that are limited solely to their location.
- Offer biased reports:
Surveys or interviews about certain aspects of the lives of individuals in a group may not always produce accurate reporting. The cross-sectional study does not usually have a mechanism to verify the information.
Before you use this research design for your study, it is important to acknowledge these limitations so that you can plan your research accordingly.
Cross-sectional Study Example
If you still have some confusion about the cross-sectional quantitative study, take a look at this following example of a cross-sectional study.
Let's assume that you want to learn how many families with children in Sydney are currently having a low-income so that you can estimate how much money is needed to fund a free lunch program at public schools in the city. Since you only need to figure out the number of low-income families, cross-sectional research should be ideal in helping you gather the data you need.
Hopefully, this blog has helped you develop a decent understanding of the cross-sectional study. To learn more about this form of research, it is advised to refer to your instructor and conduct preliminary research on your own. Good luck!