The Usability Pattern Inspection (UPI) is a new usability inspection method designed for the added downstream utility of producing concrete design recommendations. This paper provides first empirical evidence that UPI measures up to the established inspection method Heuristic Evaluation (HE) regarding defect identification. It is shown that there is also some potential for synergy between UPI and HE. The further research plan of measuring UPI is presented. Categories and Subject Descriptors H.5.2 [User Interfaces (e.g. HCI)]: Evaluation/methodology General Terms Measurement, Human Factors Keywords Usability Inspection, Experiment, Evaluation, Usability Patterns