Question

What is the relationship between reliability and validity: Is it possible for a measure to be reliable and invalid? Conversely, is it possible for a measure to be unreliable and valid?

Answer 1

Reliability is the consistency of the measure and validity is the accuracy of the measure that is used. Reliability and validity are the most important part that should be used to conduct a research study. The tool for the data collection used for the research should be compulsory reliable and valid.

It is possible to measure reliable but not valid. The instrument or tool use for the data collection may be reliable that is getting the same score in repeated checking but it does not mean that it measures what is suppose to be measured for the data collection.

All the validity of measurement is present then usually the measurement also will be reliable. So it is not possible that valid measurement but not reliable.