Determination of the Reliability of Guidewires' Visibility Measurement

In this study, the repeatability (variation in measurements) and reproducibility (precision between measuring persons) of a measuring method, developed by us, for quantifying the visibility of guidewires was investigated. Visibility was determined on a percentage scale against the background. The measuring method was tested by two persons with three repeats using X-ray images. Images were made from ten guidewires with the same material and type. X-ray images were made with the same settings on different days. Coefficients of variation (standard deviation as a proportion of the mean) for three repeats did not exceed 0.10 in measurement. Therefore, our method was repeatable. The average difference between the persons was 4 %, therefore our method was reproducible. Coefficients of variation for the mean of the ten images were under 0.10. Therefore, the images made with the same settings on different days could be averaged in case of the same samples. Significantly, there was a difference (p = 0.04) between the three tests by the first person. There were no significant differences in case of the second person (p = 0.74), and between the three-three test (p = 0.21). Using this method, available guidewires can be tested under laboratory conditions, so they may become comparable based on their visibility.