Coding medical concepts: a controlled experiment with a computerized coding tool.

In medicine there is a growing need to encode medical concepts with the available standard coding systems. The coding process can be time intensive and may significantly add to daily paperwork. We have developed a generic computerized encoding tool--the PADS (patient archiving and documentation system) encoder--to ensure rapid, correct and complete coding of diagnoses in daily routine. The tool is integrated into an electronic patient record system and takes full advantage of the user friendly Macintosh interface. The tool was tested in a controlled experiment by 18 clinicians who encoded a total of 666 medical concepts in each protocol (study protocol versus control). We present data demonstrating that a computerized coding tool can produce more complete data of higher quality and save time compared with the traditional approach: (a) the number of correctly encoded medical concepts was higher (99.55% versus 86.1%); (b) coding errors were lower (0% versus 10.81%); (c) more modifier codes were encoded correctly (increase by up to 43%); (d) fewer coding errors were made (decrease by up to 43%); (e) the overall rate of correctly encoded and complete main and modifier codes was increased by 31.27% (97.29% versus 66.02%); and (f) coding time was reduced by 50%.