Use of the transtheoretical model in the medication use process

To review articles published during the past 10 years relating to the transtheoretical model (TTM) and the medication use process, focusing on prescribing, dispensing, and using prescription and nonprescription medications for legitimate purposes.

MEDLINE, Cochrane database, PsychINFO, International Pharmaceutical Abstracts, and PubMed were searched from 1995 to August 2004 using the key terms models, psychological; prescriptions, drug; drugs, nonprescription; models, theoretical; self medication; patient compliance; medication compliance; decision making; drug therapy and behavior change. Additional searches included the following terms: pharmacists, community; TTM; transtheoretical model, pharmacy services, new practice patterns and physician practice patterns.

Studies with empirical application of any aspect of TTM were included. Abstracts were reviewed by both authors, and data were independently abstracted including, for example, specific aspects of TTM used or tested, context for model use or setting, and results and authors' suggestions for future use of TTM. The reviewers came to consensus on all abstracted information.

Eleven articles were identified that contained TTM and drug use; however, only 5 were empirical applications. There were 2 types of applications of TTM in medication use: measurement of stage of change regarding adherence and prediction of adherence using TTM concepts. A 1- and 2-item measure of adherence stage of change have been validated. Medication adherence stage of change varied by type of drug. The pros and cons of taking the medicine and stage of change were useful in predicting adherence. No intervention studies to improve adherence were identified.

TTM has not been used extensively to examine the medication use process. Without further research, no clear recommendation can be provided as to the effectiveness of TTM in improving the drug use process, but it remains promising.