Do you know what a research design is? Surely you relate it to the classes of statistics, experimental psychology… However, it is a tool that is used in many types of research and in many fields of study.

This is a set of techniques that allow a researcher to prepare his experiment or research. In this article we will know exactly what it consists of, what types exist and how some variables influence its design.

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What is research design?

Before explaining how these designs work and what types exist, let’s see what a research design is, or how it is defined. This is a set of techniques and methods chosen by a researcher to carry out an experiment or a research project . It is a series of steps that serve as a guide for the researcher.

Thus, in other words, research design is a structured and specific plan of action, aimed at designing and implementing an experiment. It encompasses a set of rules or concrete steps that allow the researcher to reach his objective, in this case, to develop an experiment (whether observational, experimental, quasi-experimental…).

In other words, they make it possible to create research projects; they establish the steps necessary to reach them.

Scientific method

The research design is part of the scientific method, which consists of a general procedure characterized by systematization and control. The scientific method (and therefore the research design) is divided into two: quantitative and qualitative.

1. Quantitative design

In the design or quantitative method, the phenomena are events determined by causes independent of human will, and therefore are objective. In this case, this type of research can be carried out when it is important for the researcher to obtain statistical conclusions that will help him to gather information for his investigation. In other words, it is based on calculation and numbers

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2. Qualitative design

In the qualitative, on the other hand, reality is considered as a subjective construction, in which many constructions of the same reality are possible; moreover, in this case the subject and the object of knowledge are interdependent.

In addition, qualitative research allows relationships to be established between the data collected; on the other hand, the different theories that relate to natural phenomena can be checked (refuted or proven) through this design and the corresponding mathematical calculations. Many times this type of design aims to answer open questions, such as: “why?

Methodology

What methodology is used to develop a research design? It can be of different types: deductive, inductive and hypothetical-deductive. Deductive methodology is that which goes from the general to the particular (emphasizing the theory); inductive methodology is that which goes from the particular to the general (emphasizing the data), and finally hypothetical-deductive methodology is that which combines the two previous ones.

Degree of control

In addition, depending on the degree of control we want to have in our experiment, the research design can be of 4 types . We will detail them below.

1. Experimental design

The experimental research design is the one with the maximum degree of control (by the researcher); that is, there is manipulation of the variables. In addition, it allows causal relationships to be established between variables.

2. Comparative design

The comparative design, in turn, is divided into two more: the correlational design (when there is a degree of relationship between the variables; it does not allow causal relationships to be established) and the comparative design itself (where the independent variable is one of selection; that is, the subject comes with its “place” value [for example, race or gender]).

On the other hand, through the proper comparative design, quasi-causality relationships can be established. In both types of comparative designs the degree of control by the experimenter is intermediate.

3. Observational / survey design

This type of research design has a minimal degree of control by the researcher; that is, there is no manipulation, it is simply observed. As in the case of the correlational design, this type of design does not allow for the establishment of causal relationships between variables.

An example of observational research design is surveys.

Type of handling

Closely related to the previous section, we ask ourselves: What kind of manipulation can be done in a research design?

Logically, it will depend on the type of design and experiment. There are basically three types of research designs depending on the type of manipulation applied to the independent variables.

1. Experimental research

This first research design involves an intentional manipulation of the independent variables. In addition, there is randomization of these variables.

2. Quasi-experimental research

In this second type, the manipulation is selective, not intentional (that is, it is about variables or values that the subject already possesses; for example, sex). In this case there is no randomization of the variables (in fact, this is the main difference between an experimental and quasi-experimental research design).

3. Non-experimental research

Finally, in non-experimental research there is no manipulation of variables or randomization of variables.

The variables in the research

Another important concept that we must know in order to understand well what research design is are the variables in research , since all of them have them. What do they consist of?

A psychological variable is a psychological construct that can be measured with mutually exclusive values (e.g. gender, anxiety level, degree of well-being, weight, height, etc.). Variables can be of different types (according to different classifications). One of the most important is the one that divides them into:

1. Dependent variables

The dependent variable, usually expressed by “Y”, is the effect produced by the independent variable. For example, it can be the degree of anxiety (which increases or decreases depending on a treatment).

2. Independent variables

The independent variables, however, are represented by “X”, and are the cause of the effects. That is, following the previous example, it would be the psychological treatments (independent variable), for example, that influence the degree of anxiety (dependent variable).

Meta-analysis

Finally, another interesting concept to know in relation to research designs is the meta-analysis; it is a technique to evaluate the quantitative results of a set of empirical studies. Through it, a summary or synthesis of the significant effects of the variables studied is reached.

This is a type of methodology consisting of the systematic review of different studies and results; through it, a series of statistical techniques are applied with the aim of analysing these results, mainly in a quantitative way.

Bibliographic references:

  • Anguera, M.T., Arnau, J., Ato, M. et. al. (1998). Research methods in psychology. Madrid: Síntesis.

  • Fontes de Gracia, S., García, C. and Quintanilla, L. (2010). Fundamentals of research in psychology. Madrid: UNED.

  • Kazdin, A.E. (2002). Research methods in clinical psychology. Mexico: Prentice Hall.