Final answer:
A psychologist using a normative approach compares a patient's assessment scores with the established norms of the general population, rather than relying on personal judgment or previous individual scores.
Step-by-step explanation:
When considering a normative approach to interpreting a patient's score on an assessment instrument, the psychologist is interested in comparing the patient's score with norms established for the general population. Norms serve as a reference point and are not expectations but rather an aggregation of data showing what a certain group knows or how they perform on a particular assessment.
The establishment of norms comes from testing a large population to gather data, offering a means to compare individuals to a representative sample that accurately represents the general demographic of interest. This practice allows for a consistent interpretation of results over time, as seen with the Stanford-Binet Intelligence Scale.