semi-quantitative segmental perfusion scoring in myocardial perfusion spect: visual vs. automated analysis

introduction: it is recommended that the physician apply at least a semi-quantitative segmental scoring system in myocardial perfusion spect.  we aimed to assess the agreement between automated semi-quantitative analysis using qps (quantitative perfusion spect) software and visual approach for calculation of summed stress  score (sss), summed rest score (srs) and summed difference score (sds). methods: we retrospectively studied 1782 consecutive patients who had undergone two-day stress-rest tc99m-mibi myocardial perfusion spect. based on 17-segment 5-scale scoring system, sss, srs and sds were calculated visually and using qps software. results: there was good correlation between visual analysis and qps software in calculation of sss and srs and a fair correlation for sds. however, there was statistically significant difference between two methods. by bland-altman analyses mean value of the differences (estimated bias) differs significantly from 0 on the basis of 1-sample t-test. based on bias, precision and 95% limits of agreement, discrepancies between measurements indicate no agreement equally through the range of measurements, so there is a proportional bias. based on sss, srs and sds ≤3 and sss, srs and sds >3, there was fair concordance between the visual assessment and automated qps calculation. kappa statistics was 0.41 (p