INTERNAL VALIDITY IN RESEARCH 2

Internal Validity in Research

Internal validity ensures that there is very high confidence in the relationship of cause and
effect. When a research has high internal validity there are very few, if any, alternative causes
that explain the results or observations made thus ensuring that the principle of cause and effect
is closely adhered to (Patten & Newhart, 2017). A good experiment should have strong internal
validity so that there can be no doubt about the cause-effect relationship that it establishes. It is,
therefore, important that a researcher employs a design approach that has high internal validity.
Each of the approaches discussed has their strengths and weaknesses. As far as internal
validity is concerned I believe that the best design approach that guarantees integrity of internal
validity is experimental research. This design is arguably the most rigorous of the approaches
discussed. In the design the researcher manipulates one or more independent variables as
treatments. The researcher then randomly assigns subjects to different levels of treatment. They
then observe the results of the treatments on dependent variables or outcomes and record them
for analysis (Campbell & Stanley, 2015).
The main strength of experimental research is its ability to effectively establish causality
or internal validity. This is because it eliminates biases in subject selection which is one of the
main threats to internal validity. The threat is usually eliminated through randomization. In
experimental research, the research subjects are usually assigned randomly to different levels of
treatment. This randomization helps to strengthen internal validity. Additionally, experimental
research design also controls spurious effects of non-essential variables. The combination of
these controls and randomization enables experimental research design to have strong internal
validity in all circumstances.

INTERNAL VALIDITY IN RESEARCH 3

References

Campbell, D. T., & Stanley, J. C. (2015). Experimental and quasi-experimental designs for
research. Ravenio Books.
Patten, M. L., & Newhart, M. (2017). Understanding research methods: An overview of the
essentials. Routledge.