Dissertations and research projects

Reliability and validity

It is important that you show rigour within your research. This means demonstrating that you have given careful consideration to how you can enhance the quality of your research project. Within quantitative research this is achieved through examining reliability and validity.

• Reliability – is a measure of how consistent, dependable and repeatable something is.
• Validity – is the extent to which research measures the concept that it was designed to measure.

For example, if you had some scales that were always weighed an object as 5kg lighter than it actually is, this would be an example of a measure that was very reliable but not valid: the scales will always give you a consistent measure of weight, but this measure is not accurate.
 

There are several different types of reliability and validity that you should consider when planning, conducting and writing up your research project. For more information on the different types of reliability and validity have a look at the recommendations below:

• Designing and Doing Survey Research (Andres, 2012) – see Chapter 7.
• Quantitative Health Research Issues and Methods (Curtis & Drennan, 2013) – see Chapter 16.
• Research Methods in Psychology (Howitt & Cramer, 2017) – see Chapter 16.