Studies that evaluated the accuracy of DW-MRI for diagnosis of malignant hepatic lesions and that reported sufficient data to construct a 2x2 table of test performance were eligible for inclusion. Inclusion criteria were not defined in terms of reference standard, but studies were required to report details of the reference standard used in the methods section.
Included studies were conducted in Japan, France, Netherlands, Germany, Turkey, Greece, Belgium, UK and USA. All studies used 1.5 Tesla scanner systems. Where reported, thresholds on DW-MRI ranged from 1.47 to 5.5 x103mm/s2. Reference standards consisted of combinations of surgical specimens/resection, biopsy, follow-up imaging, pathology and clinical follow-up.
Two reviewers independently selected studies for inclusion; disagreements were resolved through consensus.