How to evaluate the validity of a questionnaire survey?

Questionnaire validity assesses whether a survey instrument accurately measures its intended constructs. Validity can be empirically evaluated through specific statistical methods and expert judgments. Key aspects include content validity, determined via expert review to confirm item relevance and coverage. Criterion validity examines correlations with established external measures. Construct validity is paramount, assessed through factor analysis to verify that items load on their hypothesized latent factors, convergent/discriminant validity testing, and internal consistency evaluation. Adequate sample size is essential for reliable statistical testing. Attention must also be paid to wording clarity and cultural appropriateness. To evaluate validity, first perform expert review during design. Subsequently, conduct a pilot study to collect data. Analyze this data statistically: calculate internal consistency reliability (e.g., Cronbach's alpha), perform exploratory or confirmatory factor analysis to examine dimensionality, and test convergent/discriminant validity using correlations or multi-trait multi-method matrices. This process ensures measurement accuracy, enhances research credibility, and supports sound conclusions based on survey findings.