What is the most critical issue that a professional should consider when selecting an intelligence testing instrument

When selecting an intelligence testing instrument, the most critical issue a professional should consider is validity. Validity refers to how well a given test accurately measures what it is intended to measure (Weiten, 2020). It is essential for professionals to choose tests that are valid and reliable in order to ensure accurate assessments of their clients’ cognitive abilities. A valid intelligence testing instrument must be based on sound psychometric principles and provide results that reflect an individual’s true level of intellectual functioning (Kurzweil, 2015).