[Discarding medical images and its evaluation].
Following a survey of our filing system, the period of storage of medical images was generally limited to ten years, a system which was put into execution in 1990. Film jackets older than ten years are discarded every year, except for those registered for permanent storage. Fourteen thousand jackets (6.5% of total) have been registered for permanent storage. A follow-up survey has been performed to evaluate this system. The survey focused mainly on the frequency of re-issue of film jackets, and the rate of access to jackets. Discarded jackets now number about 50,000, a reduction of 20%. A total of 405 jackets were re-issued in a year due to the re-examination of patients whose jackets had been discarded. The annual number of re-called jackets from the repository outside our hospital was about 2,200 (about 500 of them were for research work), which corresponded to 1.5% of the patients re-examined in the radiology department. The new filing system has been well integrated into the hospital daily routine. Information cost was calculated as a function of access rate to the stored information, and the concept of "cost-of-information" was proposed as a measure of cost analysis of an information system.
Imamura
K
K
Department of Radiology St. Marianna University.
Oyama
Y
Y
Ishikawa
T
T
Nemoto
Y
Y
Morita
S
S
D003365:Costs and Cost Analysis; D005371:Filing / Q000191:economics / Q000379:methods*; D006801:Humans; D007564:Japan; D011872:Radiology Department, Hospital / Q000458:organization & administration*; D011873:Radiology Information Systems / Q000458:organization & administration*