Rather than doing a new study, the researchers searched the medical literature from January 1983 through January 2003. They found 78 studies that involved patients with suspected DVT or PE who had a d-dimer blood test. d-Dimer tests that were studied included enzyme-linked immunosorbent assays (ELISA), quantitative latex agglutination assays, semi-quantitative agglutination assays, and whole-blood agglutination assays. All of the patients in the studies also had standard tests for DVT or PE, such as venography, compression ultrasonography, lung scans, or pulmonary angiography. The researchers combined the findings of the studies to see which of the d-dimer tests were most helpful in detecting DVT or PE that was confirmed with standard tests.