Validity refers to whether a set of survey questions is measuring what it is intended to measure.
Steps for establishing the validity of an OurSCHOOL measure
- Determine a theoretical definition of the construct by reviewing literature, and by seeking expert opinion.
- Identify the questions that reflect the construct through thorough discussions with experts, as well as teachers and students in focus groups, and a review of other instruments.
Data are analyzed using two psychometric techniques: factor analysis and item response theory (IRT). The analysis provides an indication of how well the questions hold together to provide a measure of a single unified construct, and whether each question contributes to the reliable measurement of the construct.