Suitability of indexing terms in the MEDLINE bibliographic database on drug-related problems.

There was a very good direct exponential trend of the overall scientific output retrieved with the terms associated with DRPs, although the progression of the five descriptors separately did not show a growth model conforming to expectations. There was a moderate agreement between the objective of the study and the definition of each of the five descriptors used and a low relationship between the objective of the study and the concept of DRPs used for this investigation. It is essential to have a descriptor that unifies the terminological diffusion that has existed up till now, since process (causes) and effects (outcomes) have been mixed together under the various definitions and classifications of DRPs found in the studies.