Djurre Zijsling

How physicians choose drugs.

A drug choice model which includes the physicians attitudes, norms and personal experiences with drugs, was tested. One hundred and sixty-nine physicians were asked to estimate the models components for the treatment of irritable bowel syndrome (IBS) and of renal colic. Given three drugs for both indications, the physicians gave their expectancies about the treatment outcomes, professional acceptability, patient demand and their personal experiences with the drugs. They also stated the value they assign to each of these components when choosing a drug for IBS and for renal colic. The influence of patient demand on the choice of a specific drug appeared to be negligible. The combined effect of the other three elements of the model predicted the stated drug of first choice correctly in 74% (for IBS) and 78% (for renal colic) of the cases, but further analysis showed that only the drug choices for renal colic were as reasoned as the model assumed. Expectancies and values about treatment outcomes determined the drug choice only in part. For choosing a drug for renal colic, the professional environment was more important. Moreover it was found that drug preferences were more related to expectancies about efficacy than to expectancies about side effects for both disorders. The findings can be useful when trying to change prescribing behaviour. Only a limited effect can be expected from the provision of technical drug information. Especially information about costs is unlikely to change prescribing easily, unless values and norms are changed as well. The importance of the professional environment implies that educational programmes in groups might be more effective than individual approaches.

IMPACT OF A DRUG BULLETIN ON THE KNOWLEDGE, PERCEPTION OF DRUG UTILITY, AND PRESCRIBING BEHAVIOR OF PHYSICIANS

The impact of a drug bulletin was tested in a randomized controlled trial that included 186 family physicians. The length of the trial was six months. It was hypothesized that printed information, such as in drug bulletins, influences physician prescribing behavior by changing their knowledge of drug efficacy and adverse effects and their perceptions of drug utility. Therefore, the impact of a drug bulletin was evaluated on these domains of influence. Interview data were used to assess changes in knowledge, perceived drug utility, and stated prescribing. Health insurance funds’ records were used to collect actual prescribing data. Information in the bulletin on the treatment of renal colic changed physicians’ knowledge as well as perceived utility of drugs used for renal colic (p<0.05). Significant changes in stated prescribing were also found. On the other hand, advice in the same bulletin on the treatment of the irritable bowel syndrome (IBS) had no impact at all. It did not even improve the knowledge of the physicians about the drugs used for IBS. Apparently, the message about the treatment of IBS failed to gain the attention of the physicians. It is suggested that some messages are sufficiently transmitted through written information, and others that are seen as less relevant or too difficult to implement need more intensive strategies.