The importance of request and report forms in the interpretation of therapeutic drug monitoring data.

The interpretation of therapeutic drug monitoring data depends not only on the measurements themselves but also on additional data collected on the request forms and the manner in which the results are displayed on the report forms. A study was conducted to learn how presently used request/report forms affect the interpretation of therapeutic drug level measurements. Letters were sent to 232 directors of laboratory services requesting them to forward examples of forms that they use in therapeutic drug monitoring and toxicology. Replies were received from 77 directors of whom 53 enclosed examples of their therapeutic drug monitoring request/report forms. The characteristics of the 53 request/report forms were analyzed, and the results indicate that request/report forms are not optimally configured to facilitate effective therapeutic drug monitoring. Many request forms are not designed to allow entry of even the most basic data essential to the interpretation of therapeutic drug level measurements. Many report forms do little more than provide a drug level measurement and a therapeutic range. Improved request/report forms, as well as systems to ensure their proper use through adequate numbers of qualified personnel are necessary. Data/word processing computers should prove helpful.