Many published medical papers are available on the Internet in a PDF format, but ordinarily can't be stored by multiple-subject topics, the American Roentgen Ray Society said in a news release.

"For radiologists, these electronic papers provide richer information (through cases, reviews and images) than conventional textbooks and can be easily found and downloaded for further reading via online databases. However, managing PDF files is troublesome and it is difficult to find software designed for organizing them," said Dr. Li Jun Qian, who led the team of researchers from Renji Hospital and Shanghai Jiaotong University School of Medicine in China.

Study authors found iTunes can address the multi-subject filing question because of its search and sort functions, its ability to remember user favorites and its capability to support customized shortcuts.

"One day I just happened to drag and drop a PDF into iTunes and was surprised to find that it was supported by iTunes. This means that you can search, describe, and rate PDFs just like you do the music files," Qian said.