Domain-referenced, or criterion-referenced, test interpretation is the concept that an examinee’s scores on a test are interpreted with reference to the particular cognitive ability being assessed rather than in comparison with the performance of a population of individuals (norm-referenced testing). For example, when examining reading ability, domain-referenced interpretation is exemplified when a neuropsychologist interprets an examinee’s performance in terms of reading mastery or how the current reading level compares to a previous level of reading. This interpretation also assists in predicting the examinee’s performance on a criterion. The benefit of this type of interpretation is that it allows the referral source, patient, caregiver, or other interested parties to understand the potential impact of a deficit in the examinee’s daily life, such as particular subjects in school, various skills on a driving test, specific job duties in the workplace, or behaviors in interpersonal encounters. Regardless of the specific area being assessed, interpretation of performance in the domain under study is meaningful only if the domain content is clearly defined with the use of very specific and observable terms. An additional concept often discussed as domain-referenced test interpretation is mastery, which is the determination of whether or not an individual has mastered a particular domain or skill. Prior to the assessment of mastery, the neuropsychologist must establish the number of items or proportion of items that must be correctly answered to demonstrate mastery.