Which research methodology to use

The type of soda — diet or regular — is the independent variable. The level of blood sugar that you measure is the dependent variable — it changes depending on the type of soda.

Can a variable be both independent and dependent? Can I include more than one independent or dependent variable in a study? Why do confounding variables matter for my research? What is the difference between confounding variables, independent variables and dependent variables? How do I prevent confounding variables from interfering with my research? What is data collection? What are the benefits of collecting data?

When conducting research, collecting original data has significant advantages: You can tailor data collection to your specific research aims e. What is operationalization? What is hypothesis testing? What are the main qualitative research approaches? There are five common approaches to qualitative research : Grounded theory involves collecting data in order to develop new theories.

Ethnography involves immersing yourself in a group or organization to understand its culture. Narrative research involves interpreting stories to understand how people make sense of their experiences and perceptions. Action research links theory and practice in several cycles to drive innovative changes.

How do you analyze qualitative data? There are various approaches to qualitative data analysis , but they all share five steps in common: Prepare and organize your data. Review and explore your data. Develop a data coding system. Assign codes to the data. Identify recurring themes. What is a Likert scale? Are Likert scales ordinal or interval scales?

What is the difference between a control group and an experimental group? Do experiments always need a control group? What is blinding? What is the difference between single-blind, double-blind and triple-blind studies?

In a single-blind study , only the participants are blinded. In a double-blind study , both participants and experimenters are blinded.

In a triple-blind study , the assignment is hidden not only from participants and experimenters, but also from the researchers analyzing the data. Why is blinding important? What is a quasi-experiment? When should I use a quasi-experimental design? What is simple random sampling?

What is an example of simple random sampling? When should I use simple random sampling? However, it can sometimes be impractical and expensive to implement, depending on the size of the population to be studied, If you have a list of every member of the population and the ability to reach whichever members are selected, you can use simple random sampling. What is cluster sampling? The clusters should ideally each be mini-representations of the population as a whole.

What are the types of cluster sampling? In single-stage sampling , you collect data from every unit within the selected clusters. In double-stage sampling , you select a random sample of units from within the clusters. In multi-stage sampling , you repeat the procedure of randomly sampling elements from within the clusters until you have reached a manageable sample. What are some advantages and disadvantages of cluster sampling? What is stratified sampling?

When should I use stratified sampling? Can I stratify by multiple characteristics at once? What is systematic sampling? How do I perform systematic sampling? There are three key steps in systematic sampling : Define and list your population , ensuring that it is not ordered in a cyclical or periodic order.

Decide on your sample size and calculate your interval, k , by dividing your population by your target sample size. Choose every k th member of the population as your sample. How can you tell if something is a mediator? Why should you include mediators and moderators in a study? What is a control variable? Why are control variables important?

What is random assignment? How do you randomly assign participants to groups? When do you use random assignment? Can you use a between- and within-subjects design in the same study? What are the pros and cons of a between-subjects design?

Advantages: Prevents carryover effects of learning and fatigue. Shorter study duration. Disadvantages: Needs larger samples for high power.

Uses more resources to recruit participants, administer sessions, cover costs, etc. Individual differences may be an alternative explanation for results.

What are the pros and cons of a within-subjects design? Advantages: Only requires small samples, Statistically powerful, Removes the effects of individual differences on the outcomes. Disadvantages: Internal validity threats reduce the likelihood of establishing a direct relationship between variables, Time-related effects, such as growth, can influence the outcomes, Carryover effects mean that the specific order of different treatments affect the outcomes. What is a factorial design?

What are the types of extraneous variables? Experimenter effects : unintentional actions by researchers that influence study outcomes. What are the requirements for a controlled experiment? Controlled experiments require: A control group that receives a standard treatment, a fake treatment, or no treatment. Random assignment of participants to ensure the groups are equivalent.

What are explanatory and response variables? The difference between explanatory and response variables is simple: An explanatory variable is the expected cause, and it explains the results. A response variable is the expected effect, and it responds to other variables. How do explanatory variables differ from independent variables? How do you plot explanatory and response variables on a graph?

If you have quantitative variables , use a scatterplot or a line graph. If your response variable is categorical, use a scatterplot or a line graph. If your explanatory variable is categorical, use a bar graph. Is random error or systematic error worse? How do you avoid measurement errors? What is a correlation? A positive correlation means that both variables change in the same direction. A negative correlation means that the variables change in opposite directions.

What is correlational research? What is a correlation coefficient? How many variables are in a correlation? In an experimental design , you manipulate an independent variable and measure its effect on a dependent variable. In a correlational design , you measure variables without manipulating any of them. How do you order a questionnaire? How do you administer questionnaires?

What is a research design? What do I need to include in my research design? Why is research design important? What are the main types of research design? Quantitative research designs can be divided into two main categories: Correlational and descriptive designs are used to investigate characteristics, averages, trends, and associations between variables.

Experimental and quasi-experimental designs are used to test causal relationships. What are the assumptions of the Pearson correlation coefficient? Developing strong research questions Research questions give your project a clear focus.

They should be specific and feasible, but complex enough to merit a detailed answer. How to create a research design The research design is a strategy for answering your research questions. It determines how you will collect and analyze your data.

A step-by-step guide to data collection Data collection is the systematic process of gathering observations or measurements in research. It can be qualitative or quantitative. A guide to ethical considerations in research A guide to ethnography A guide to experimental design A guide to operationalization A quick guide to textual analysis A step-by-step guide to data collection An introduction to cluster sampling An introduction to correlational research An introduction to mixed methods research An introduction to multistage sampling An introduction to qualitative research An introduction to quantitative research An introduction to quasi-experimental designs An introduction to sampling methods An introduction to simple random sampling Constructing a conceptual framework Control groups in scientific research Control variables explained Correlation vs causation Descriptive research Designing a questionnaire Designing and analyzing Likert scales Explanatory and response variables How do you incorporate an interview into a dissertation?

How to create a research design How to do a case study How to do survey research How to do thematic analysis How to perform systematic sampling How to transcribe an interview How to use stratified sampling How to write a hypothesis Independent and dependent variables Inductive vs. Qualitative vs. Sampling bias: What is it and why does it matter?

The four types of validity The main types of research compared Types of reliability and how to measure them Understanding confounding variables Understanding external validity Understanding extraneous variables Understanding internal validity Understanding types of variables What is a between-subjects design?

What is a controlled experiment? What is a cross-sectional study? What is a double-blind study? What is a longitudinal study? What is a within-subjects design? What is content analysis and how can you use it in your research? What is discourse analysis? What is your plagiarism score? Scribbr Plagiarism Checker. Flexible — you can often adjust your methods as you go to develop new knowledge. Can be conducted with small samples. Difficult to standardize research. Can be used to systematically describe large collections of things.

Generates reproducible knowledge. Requires statistical training to analyze data. Requires larger samples. Can be collected to answer your specific research question. You have control over the sampling and measurement methods. As with interviews, you can decide to use closed or open questions, and can also offer respondents multiple choice questions from which to choose the statement which most nearly describes their response to a statement or item.

Their layout is an art form in itself because in poorly laid out questionnaires respondents tend, for example, to repeat their ticking of boxes in the same pattern. If given a choice of response on a scale , they will usually opt for the middle point, and often tend to miss out subsections to questions. You need to take expert advice in setting up a questionnaire, ensure that all the information about the respondents which you need is included and filled in, and ensure that you actually get them returned.

Expecting people to pay to return postal questionnaires is sheer folly, and drawing up a really lengthy questionnaire will also inhibit response rates. You will need to ensure that questions are clear, and that you have reliable ways of collecting and managing the data. Setting up a questionnaire that can be read by an optical mark reader is an excellent idea if you wish to collect large numbers of responses and analyse them statistically rather than reading each questionnaire and entering data manually.

You would find it useful to consult the range of full and excellent research books available. These will deal in much greater depth with the reasons for, processes of holding, and processes of analysing data from the variety of research methods available to you.

Gina Wisker. Find out more. Home Improve your study skills Research methods Choosing appropriate research methodologies. Choosing appropriate research methodologies Choosing qualitative or quantitative research methodologies Your research will dictate the kinds of research methodologies you use to underpin your work and methods you use in order to collect data.

Interviews Interviews enable face to face discussion with human subjects. If you decide to use interviews: Identify your sample. One particular method could be better suited to your research goal than others, because the data you collect from different methods will be different in quality and quantity. For instance, surveys are usually designed to produce relatively short answers, rather than the extensive responses expected in qualitative interviews.

What other factors should I consider when choosing one method over another? Time for data collection and analysis is something you want to consider. An observation or interview method, so-called qualitative approach, helps you collect richer information, but it takes time. Using a survey helps you collect more data quickly, yet it may lack details.