The overclaiming technique is a novel assessment procedure that uses signal detection analysis to generate indices of knowledge accuracy (OC-accuracy) and self-enhancement (OC-bias). The technique has previously shown robustness over varied knowledge domains as well as low reactivity across administration contexts. Here we compared the OC-accuracy index with multiple choice (MC) and short answer (SA) tests in assessing knowledge of introductory psychology topics in a sample of 108 undergraduates. Results indicated that OC-accuracy was (a) comparable to MC and SA in predicting overall course grades and (b) superior to SA tests in reliability achieved per unit administration time. By including the OC-bias index, the overclaiming method also adds a unique element to scholastic testing, namely, a measure of knowledge self-enhancement. The latter index was a "negative" predictor of overall course grade, suggesting a narcissistic self-destructiveness. Because the self-enhancement index adds no extra administration time to the knowledge measure, the overclaiming approach provides a more rich and efficient information source compared with traditional methods of scholastic assessment.