What is quantitative research and what research methods are there?

In quantitative research, you collect numerical data. This allows you to test hypotheses or theories, or calculate averages or percentages. The goal is often to reach conclusions from your data that are generalizable to a larger group. What exactly does quantitative research entail, and what quantitative research methods can you use? You can learn all about that in this article.

Quantitative research involves collecting and analyzing numerical data. For example, you administer surveys to a large sample of participants to find out averages, percentages and patterns based on their responses. This type of research is designed to confirm or reject hypotheses or theories. 

The following points are characteristic of quantitative research:

• The data you collect can be expressed in numbers or percentages.

• You often conduct research among a large sample.

• You will test hypotheses or theories with your research.

• Research is deductive: you test a theory based on newly collected data.

• Often the desired outcome is that you can generalize the results to the entire study population or to a larger number of cases. 

Quantitative research is the opposite of qualitative research. The main difference between quantitative and qualitative research is that in qualitative research you do not collect numerical data. Instead, you collect data that can be expressed in words or observations. For example, you might conduct an extensive interview with a few people in the population to get an in-depth picture of a particular phenomenon. 

Qualitative research is often conducted on a smaller scale than quantitative research. Also, the goal is different. Rather than trying to confirm or disprove a theory, you want to gain a deeper understanding of a particular phenomenon that has not been extensively studied before. Your data can reveal patterns that may help you develop a new theory. You may later conduct quantitative research to test that theory in a larger sample.

For quantitative research, there are a number of research methods you can choose from. These are some examples:

• Experiment: you investigate a hypothesis by manipulating or controlling variables in an artificial setting.

• Survey with closed questions: you ask a larger group of respondents about your chosen topic via a questionnaire. You ask closed questions, such as multiple choice questions or statements in which respondents indicate the extent to which they agree or disagree with your statement. 

• Quantitative observations: you count the number of times certain behavior or phenomenon occurs in a natural situation. This allows you to quantify your observations. 

You will also analyze the quantitative data you find. To do this, you will use a form of quantitative data analysis (statistics). Sometimes, you must first categorize or process the data in order to perform statistical analyses. For example, you have to give the answers "I completely agree" and "I agree" each a number so you can calculate their averages.

For analysis, you can use descriptive statistics. With this method, you calculate things like averages and standard deviations. These statistics can help you create graphs or tables to describe the phenomenon you observed in the study population. 

In addition, there are other forms of statistics that allow you to demonstrate relationships between variables or test hypotheses. Check your statistics textbook or ask your professor for advice on proper statistical analysis techniques. 

Whatever research and analysis method you use, it is always important that your method is valid and reliable. This means the following:

1. You made the measurements in a consistent and careful manner, minimizing the chance of random measurement errors. This makes your research reliable.

2. You can show that you measured what you wanted to measure, and that your measurement method is appropriate for the variables you selected. In other words, your research is valid.

Note that there are different types of reliability and different types of validity. Check in advance which of these apply to your research. In the methods chapter of your thesis, discuss what you have done to ensure the reliability and validity of your research.

Do you decide to do quantitative research? If so, it has a number of advantages:

• The research is precise because you are working in a structured way and often following a certain pre-established protocol.

• The results are easier to generalize because you can do research among a large sample in a consistent manner.

• Your research is replicable. Your approach to data collection is structured, and allows others to redo the research in the same way.

• You can demonstrate whether or not a hypothesis is correct based on your collected data. 

• Your results are easier to compare with others.

There are also potential drawbacks to quantitative research. The disadvantages are as follows:

• You have no deep insight into why respondents exhibit certain behaviors or hold certain opinions. The information is more general. Deeper insight requires qualitative research.

• There is a chance of measurement error, for example, if your sample is not representative or if respondents misinterpreted a question.

• You are likely to leave out potentially relevant information because of your focus on certain aspects. 

• The setting in which you conduct the research is sometimes slightly unnatural. This is true, for example, when you conduct research in a laboratory or when you have people fill out a survey under supervision.

In our knowledge base you will also find a comprehensive overview of the different research methods. In addition, you can read more about research design, making a research plan and the various research approaches. Be sure to explore our knowledge base to learn how to make good choices about the methodology for your thesis.