Validity and Reliability Handbook

The Validity and Reliability Handbook is a guide that helps ensure the tools and methods used in research or assessments are accurate and dependable. Validity checks whether a test measures what it’s supposed to measure, while reliability ensures the results are consistent over time and across different situations. Together, these concepts help researchers and practitioners trust that their findings are meaningful and not due to chance or errors. The handbook provides guidelines, standards, and best practices to develop, evaluate, and improve the quality of assessments and research instruments, ensuring they produce trustworthy and valid results.