Jakob Nielsen is well known author that has been writing about computer usability for years. His "Top Ten Web Design Mistakes" article series is by now well known and appreciated globally.
In April 2005 he wrote a small article on Medical Software Usability, named "Medical Usability: How to Kill Patients Through Bad Design". The following was taken from that article:
"A field study identified twenty-two ways that automated hospital systems can result in the wrong medication being dispensed to patients. Most of these flaws are classic usability problems that have been understood for decades."
That article's full text is available at: http://www.useit.com/alertbox/20050411.html and the full list of Nielsen's "Alertbox" articles on usability are available at: http://www.useit.com/alertbox/