Summary: | Background. Gap between number of radiologists and the need of radiology
services causes teleradiology might be a promising method in the future. One of
important issues in teleradiology is image quality. American College of Radiology
standard for teleradiology provided minimum digital image size 512 x 512 matrix size, 8
bit pixel depth, equals to 250 kilobyte (kb). In Indonesia internet connection problems
caused image transmission consumes more time. Size of the file affects transmission
speed. So far, there is no minimum standard of the file (image) size and display size for
each type of imaging in teleradiology.
Objective. To compare error rate, sensitivity, specificity and diagnostic accuracy
of bone fracture on transmitted digital image in different size which were interpreted with
different display size. Also to compare impact of image size and display size on error
rate, sensitivity, specificity and diagnostic accuracy of bone fracture.
Method. Study type was diagnostic test, comparing error rate, sensitivity,
specificity and diagnostic accuracy of bone fracture between transmitted digitized
medical image result from reproduction of hard copy image in different file size (kb and
pixel density). Also compared error rate, sensitivity, specificity and diagnostic accuracy
between small, medium dan large display size. There were 44 samples consist of 22
fractures and 22 normal bones. Result. There was significant different number of file
which subject�s identity were clearly read between small, medium and large file image
and also between small, medium and large display size (0% vs 21,5% vs 78,5%) and
(25% vs 40,3% vs 34,7%) (p<0,05). Error rate, sensitivity, specificity and diagnostic
accuracy between small, medium and large file size digital image were significantly
different (p<0,05) while those were equal between small, medium and large display size.
File size had higher impact on error rate, sensitivity, specificity and diagnostic accuracy
compared with display size.
Conclusion. File size (kb and pixel dimension) significantly affected error rate,
sensitivity, specificity and diagnostic accuracy of digital image. Small, medium and large
display size had error rate, sensitivity, specificity and diagnostic accuracy in equal term.
File size (kb and pixels) had higher impact than display size on error rate, sensitivity,
specificity and diagnostic accuracy of bone fracture in digital image.
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