Non-Experimental and Experimental Research: Research Study Design
A research design is important for ensuring the research objectives are met by properly structuring data collection and analyzing it.
Understand Research Design
What is Research Design?
A research design, also called study design, is the plan and structure specifying the methods and procedures for collecting and analyzing data to answer research questions and meet the study’s objectives.
Guide or Approaches to Research Design
By plan, we mean the overall scheme or program of research, a plan that describes how, when, and where the data are to be collected and analyzed.
By structure, we mean the conceptual framework used to specify the relationships among the study variables and answer the research questions.
The nature and objectives of a study determine, to a large extent, the research design to be employed to conduct a study.
The design of a study defines the study type (e.g., descriptive, correlational, pre-experimental, truly experimental, or quasi-experimental), research problem, hypothesis, data collection methods, and analysis plan.
Questions Research Design Must Answer
A research design will answer – what technique or techniques will be used to gather data.
This question raises the issue of whether a survey, an experiment or any other method will be employed to conduct a study.
Properties of a Good Research Design
We enumerate below a few desirable properties of good research design. These are as follows:
- A good research design is an ethical research design.
- A good research design can obtain the most reliable and valid data.
- A good research design can measure any odd events in any circumstances.
- A good research design helps an investigator avoid making mistaken conclusions.
- A good research design can adequately control the various threats to validity, both internal and external.
Guidelines for Selecting a Good Research Design
The researchers often encounter problems in selecting an appropriate research design. Here are some guidelines one can follow when choosing a research design for his or her study.
- Try to create experimental and control groups by assigning cases randomly from a single population study group.
- When a random assignment is not possible, try to find a comparison group nearly equivalent to the experimental group.
- When neither a randomly assigned control group nor a similar comparison group is available, try to use a time-series design that can provide information on trends before and after a program intervention (X)
- If a time series design cannot be used, as a minimum, and before a program starts, try to obtain baseline (pretest) information that can be compared against post-program information (a pretest-posttest design).
- If baseline (pretest) information is unavailable, be aware that we will be limited in the type of analysis we can conduct. We should consider using multivariate analytic techniques.
- Always keep in mind the issue of validity. Are the measurements true? Do they do what they are supposed to do? Are there possible threats to validity (history, selection testing, maturation, mortality, or instrumentation) that might explain the results?
The experimenter must consider ethical, practical, administrative, and technical issues in all cases.
Types of Research Design
Although no simple classification of research design covers the variations found in practice, several classifications of the research designs are possible depending on the type of studies adopted.
From the standpoint of research strategies, two broad classifications of research designs are infrequent.
Non-Experimental Study
A non-experimental study is one in which the researcher just describes and analyzes researchable problems without manipulating or intervening in the situations.
Non-experimental studies include, among others, the following types of studies:
- Exploratory studies.
- Descriptive studies.
- Causal studies.
Exploratory Studies / Exploratory Research
An exploratory study(also called exploratory research) is a small-scale study of relatively short duration, undertaken when little is known about a situation or problem. An exploratory study helps a researcher to
- Diagnose a problem;
- Search for alternatives;
- Discover new ideas;
- Develop and sharpen his concepts more clearly;
- Establish priority among several alternatives;
- Identify variables of interest;
- Set research questions and objectives;
- Formulate hypotheses;
- Develop an operational definition of variables;
- Improve his final research design.
The exploratory study helps to save time and money. If the problem appears not as important at first sight, a research project may be abandoned at the initial stage.
Exploratory study progressively narrows the scope of the research topic and transforms the undefined problems into defined ones, incorporating specific research objectives.
An exploratory study ends when the researcher is fully convinced that he has established the major dimension of the research, and no additional research is needed to conduct the larger study.
Descriptive Studies / Descriptive Research
The objective of a descriptive study is to focus on ‘who,’ ‘what,’ ‘when,’ and ‘how’ questions. The simplest descriptive study aims at
- Describing phenomena or characteristics associated with a population by univariate questions;
- Estimating the proportions of a population that has the characteristics outlined above and
- Discovering association (but not causation) among different variables.
Descriptive studies may be carried out on a small or large scale. Such a study may often be completed within a few months or weeks or even within a few hours.
Causal Studies / Causal Research
A causal research/study, also called an explanatory or analytical study, attempts to establish causes or risk factors for certain problems.
Our concern in causal studies is to examine how one variable ‘affects’ or is ‘responsible for changes in another variable. The first variable is the independent variable, and the latter is the dependent variable.
Experimental Research / Experimental Study
An experimental study/experimental research design is one in which the researcher manipulates the situation and measures the outcome of his manipulation. This contrasts with a correlational study, which has very little control over the research environment.
The experimental study exercises considerable control over the environment. This control over the research process allows the experimenter to attempt to establish causation rather than mere correlation. Thus, the establishment of causation is the usual goal of the experiment.
FAQs
What are the two main classifications of research designs based on research strategies?
The two main classifications of research strategies based on research strategies are non-experimental and experimental designs.
What is a non-experimental study?
A non-experimental study is one where the researcher describes and analyzes researchable problems without manipulating or intervening in the situations. It includes exploratory studies, descriptive studies, and causal studies.
What is the purpose of an exploratory study?
An exploratory study, also called exploratory research, is a small-scale study undertaken when little is known about a situation or problem. It helps diagnose problems, search for alternatives, discover new ideas, establish research priorities, identify variables of interest, and improve the final research design.
How does a descriptive study differ from a causal study?
Descriptive research describes the characteristics of a population or phenomena, focusing on ‘who,’ ‘what,’ ‘when,’ and ‘how’ questions. In contrast, a causal study, also known as an explanatory or analytical study, attempts to establish causes or risk factors for certain problems by examining how one variable affects another.
What is an experimental research design?
An experimental research design is one where the researcher manipulates the situation and measures the outcome of this manipulation. It exercises considerable control over the research environment, allowing the experimenter to attempt to establish causation rather than mere correlation.
What are some properties of a good research design?
A good research design should be ethical, obtain the most reliable and valid data, measure any odd events in any circumstances, help avoid making mistaken conclusions, and adequately control various threats to both internal and external validity.