15283-B-Blokker

58 Chapter 4 Sevenstudiesexaminedtheaccuracyofnon-invasiveautopsymethods, andninestudies the accuracy of various minimally invasive methods. In twelve studies a conventional autopsy (reference standard) was performed on all cases within the examined group. 57,80,102,105-112,114 In only eight studies the description of the comparison between new method and reference standard could be interpreted as blind. 57,59,80,105,106,110,111,114 Complete 2x2 tables for cause of death were extracted from two articles, 103,107 for overall findings from another article, 57 and for new major findings and cultures from yet another article. 107 In addition, partial 2x2 tables could be extracted from eleven studies. 59,80,104-106,108-112,114 For each available agreement percentage and sensitivity for cause of death in table 3, we calculated the exact binomial confidence interval. We plotted these confidence intervals in forest plots (see figure 2). They were often very wide, due to small study groups. We plotted both agreement and sensitivity in a funnel plot (see figure 3), and could not detect any signs of publication bias. Agreement and accuracy of non-invasive autopsy methods As a potential alternative to the conventional autopsy, the earliest two studies examined the use of magnetic resonance imaging (MRI). 110,111 Three other studies used (multi detector) computed tomography, (MD)CT. 59,103,104 The two most recent studies performed both MRI and CT, 102,114 but only one of them combined the results to define a cause of death. 102 This latter study included more cases than all other non-invasive studies together. The results of these studies, except Puranik et al., 114 suggest that the non-invasive autopsies using CT perform somewhat better than those using MRI. The highest sensitivity achieved with CT was 70.8%. 104 The one study combining MRI and CT achieved an agreement of 70% in cause of death. 102 Other outcomes, such as sensitivity for major findings, could only be extracted from three studies. These outcomes could not be compared, due to the heterogeneity in study methods. The criteria for case selection were various, and studies with similar patient groups investigated different imaging methods.