Psychological Research Scientific Method Reliability Validity

The scientific method is an essential component in conducting psychological research. The goal with psychological research is to produce findings that have credibility in the scientific community. The terms often used for credibility are validity and reliability. Validity means the study actually measures what it purports to measure. Reliability is the likelihood that findings will be replicated in future studies.

The scientific method introduces confidence in the validity and reliability of studies. The steps in the scientific method in psychological research include:

Identify the problem and formulate a hypothesis Design an experiment Perform the experiment Interpret findings Communicate findings

Identify the Problem and Formulate a Hypothesis 

The first step in psychological research is to define the problem. What does the researcher want to know? Is the goal to describe a phenomenon or to explore possible relationships between variables?

The second step in study design is to base the study on a clearly defined theory and hypothesis. A hypothesis is a statement predicting the outcome of the study. Psychological research may require a simple predictive hypothesis based on the findings of descriptive studies such as surveys or interviews. Psychological research often includes correlations between pre-existing variables or by manipulating variables. This type of research typically requires a hypothesis predicting an effect between variables and a null hypothesis predicting no effect between variables.

Design an Experiment 

The second step in psychological research is to design the experiment. What would be the best type of research to conduct in order to discover what the researcher wants to know? Psychological research falls under three main types.

Descriptive – Studies emphasizing observations, case studies, and describing phenomena. Correlational – Studies examining and measuring the potential relationships that exist between two pre-existing variables. Experimental – Studies examining possible cause and effect relationships that occur after manipulating variables.

Another important part of study design is explaining the rationale for the study. Why is this study important? The rationale will include the need to define terms used in the study and explain how validity and reliability concerns will be addressed. For example, what are the sampling procedures? How will confidentiality be maintained? What instruments will be used and why?

Perform the Experiment 

The methods used in conducting the experiment need to be clearly defined and followed by researchers. A critical part of achieving reliability with the study’s findings is to follow the established protocol in gathering, managing, and reporting findings. Ethical practices are critical in the management of findings.

Interpret Findings

The type of research will dictate the type of statistics that will be required to interpret findings. The validity and reliability of findings will depend upon the use of the appropriate statistical measures. Researchers must allow the findings to speak for themselves. Alterations to findings such as trimming the mean must follow the guidelines for such practices.

Communicate Findings 

The final state in psychological research is communicating or reporting the findings. Confidentiality concerning subject identification is necessary. Findings must be reported accurately and fully. Findings should be reported with clarity to avoid confusion. Conclusions should be consistent with the findings.


Research is an important part of psychological research. The findings must have validity and reliability to be of value. The credibility of research will improve if researchers follow the scientific method.