A test score interpretation always involves an interpretive argument, with the test score as a premise and the statements and decisions involved in the interpretation as conclusions. The inferences in the interpretative argument depend on various assumptions, which may be more-or-less credible. For example, inferences from test scores to nontest behavior involve assumptions about the relationship between test behavior and nontest behavior; inferences from test scores to theoretical constructs depend on assumptions included in the theory defining the construct. Because it is not possible to prove all of the assumptions in the interpretative argument, it is not possible to verify this interpretive argument in any absolute sense. The best that can be done is to show that the interpretive argument is highly plausible, given all available evidence.