This paper describes an investigation on the impact of selecting a specific defect type in software inspection. We conducted a controlled experiment concerning the effect of selecting a defect type on software inspection. In the experiment, 32 practitioners were randomly assigned to three groups performing (a) inspection without a selected defect type, (b) inspection with a selected defect type determined at the beginning of inspection, and (c) inspection with a selected defect type determined at the beginning of inspection and at every defect detection, verification of whether the detected defect is categorized as the selected defect type. The results of the experiment show that specifying the selected defect type increases the proportion of defects detected of the selected type to other detected defects. The difference between the results of groups (a) and (b) indicates that in ordinary inspections, the procedure employed by group (b) should provide higher efficiency.