<strong><span style="font-family: TimesNewRomanPS-BoldMT;"><font face="TimesNewRomanPS-BoldMT"><p align="left"> </p></font></span><p align="left"><span style="font-size: x-small; font-family: TimesNewRomanPS-BoldMT;"><span style="font-size: x-small; font-family: TimesNewRomanPS-BoldMT;">ABSTRACT</span></span></p></strong><span style="font-size: x-small; font-family: TimesNewRomanPSMT;"><span style="font-size: x-small; font-family: TimesNewRomanPSMT;"><p align="left">Much of our knowledge of drugs originates from clinical trials of drug efficacy performed on stringently</p><p align="left">selected patient groups, often without multiple concurrent diseases. However, the effectiveness of treatment</p><p align="left">under conditions of use in ordinary clinical practice may be very different to conditions in the</p><p align="left">randomised clinical trial. Use of large computerised data bases and record linkage has thus become</p><p align="left">increasingly common in pharmacoepidemiologic research. The greatest advantages of using routinely</p><p align="left">collected data are the minimisation of study costs and time required to complete a study, considerations</p><p align="left">that are particularly relevant for longitudinal studies. The advantages of using data bases also include the</p><p align="left">possibility of obtaining large sample sizes and to retrospectively study long-term outcomes. The risk for</p><p align="left">recall bias, a significant problem in interviews and questionnaires, is also reduced. However, computerised</p><p align="left">data bases also have some potentially serious disadvantages, primarily in the areas of data validity</p><p align="left">and data availability. The Tierp study, including individually based data bases of prescription drug use,</p><p align="left">will be used here as an example of research. In this paper an example of a comprehensive data base study</p><p align="left">concerning health care and drug utilisation in depressed patients is presented. Methodological considerations</p><p align="left">in data base research are discussed in relation to experiences from the antidepressant study. A well</p><p align="left">planned and research oriented computerised data base on prescription drugs represents an important tool</p><p>in the study of the outcome of drug treatment in real world clinical practice.</p></span></span>
Computerised data bases on prescription drug use and health care in the community of Tierp, Sweden: Experiences and challenges from a study of antidepressant-treated patients