Inspection and testing are common verification and validation (V&V) approaches for defect detection and removal in the software development processes. Testing approaches require executable code, typically available in later life-cycle phases. Software Inspection is a defect detection technique applicable to early life-cycle documents, e.g., during design. The Usage- Based Reading (UBR) technique approach is a structured method for inspection support. In this paper we introduce a testing variant, usagebased testing (UBT-i) that integrates testing scenarios and inspection techniques. UBT-i is a paper based testing approach (i.e. a desk test without the need for executable software) applicable to design specifications. We present an initial empirical study on defect detection effectiveness and efficiency with respect to several defect severity classes and defect locations (code or design). Main results of the study are (a) UBR and UBT-i perform similarly regarding both effectiveness and efficiency and (b) the approaches focus on different defect classes regarding defect severity and defect location.