AbstractThe Test of Language Development‐Primary is a recently published, comprehensive measure of young children's general language development. The manual provides much information on test development and standardization of the scale relevant to traditional normative interpretation, but says little about the statistical basis for profile analysis of the various subtest scaled scores. The present paper provides the necessary information for determining statistically reliable strengths and weaknesses in the performance of a single individual on each subtest, as compared to the mean level of performance across all subtests. Provided at each of five age levels are the standard errors of the difference between each score and the mean of all scores and the differences required for statistical significance at .05 and .01 significance level