Reliability of the image evaluation system PGMI

TitleReliability of the image evaluation system PGMI
Publication TypeConference Paper
Year of Publication2010
AuthorsN. Meystre, R, Bulliard, J-L, Ducros, C, Guerry, E, Ledermann, D, Lepori, D, Watrin, M, Meuwly, JY
Conference NameECR 2010, 22nd European Congress of Radiology
Conference LocationVienna, Austria, March 4-8, 2010
ISBN Number1869-4101
Accession Numberserval:BIB_7F2B37446A92

Purpose: Many countries used the PGMI (P=perfect, G=good, M=moderate, I=inadequate) classification system for assessing the quality of mammograms. Limits inherent to the subjectivity of this classification have been shown. Prior to introducing this system in Switzerland, we wanted to better understand the origin of this subjectivity in order to minimize it. Our study aimed at identifying the main determinants of the variability of the PGMI system and which criteria are the most subjected to subjectivity.
Methods and Materials: A focus group composed of 2 experienced radiographers and 2 radiologists specified each PGMI criterion. Ten raters (6 radiographers and 4 radiologists) evaluated twice a panel of 40 randomly selected mammograms (20 analogic and 20 digital) according to these specified PGMI criteria. The PGMI classification was assessed and the intra- and inter-rater reliability was tested for each professional group (radiographer vs radiologist), image technology (analogic vs digital) and PGMI criterion.
Results: Some 3,200 images were assessed. The intra-rater reliability appears to be weak, particularly in respect to inter-rater variability. Subjectivity appears to be largely independent of the professional group and image technology. Aspects of the PGMI classification criteria most subjected to variability were identified.
Conclusion: Post-test discussions enabled to specify more precisely some criteria. This should reduce subjectivity when applying the PGMI classification system. A concomitant, important effort in training radiographers is also necessary.


Citation Key / SERVAL ID5239


Institute of Social and Preventive Medicine
Route de la Corniche 10, 1010 Lausanne - Switzerland
+41 21 314 72 72 |

Go to top