INFLUENCE OF DIFFERENT SOURCES OF THERAPEUTIC INFORMATION ON PRESCRIBING BY GENERAL PRACTITIONERS

Usage of Information Sources by General Practitioners1

Questionnaires were sent to approximately 500 general practioners in five areas of one National Health Service Region; there was a 52% response. Certain characteristics of each general practitioner, which were collected from the questionnaire and medical lists, were used to assess how information was used by different ‘types’ of general practitioner. Generally, sources of information emanating from the pharmaceutical industry are used more to introduce the new product, while the ‘professional’ sources such as medical journals are used more to evaluate it. Younger doctors used Drug and Therapeutics Bulletin more than did their colleagues, and single-practice doctors found the representative to be more useful than did joint-practice doctors.

Drug promotion — A source of information about drugs?

In this paper we attempt to assess whether, or not, drug promotion is an acceptable source of drug information. Both National Health Service hospital doctors and general practi tioners are exposed to an average of $ 1000 of pharmaceuti cal prbmotion (per doctor) each year. Representatives account for 44% of this cost, and the average general practi tioner sees at least one representative per week. Very little is known about the information that representatives provide to doctors, although there are guidelines concerning conduct in the Medicines Act of 1968, and in the Voluntary Code of Practice of the Association of the British Pharmaceutical Industry (ABPI). Surveys show that doctors consider inform ation provided by representatives to be important for learn ing about both product existence and efficacy. Surveys also suggest that journal advertisements are a poor source of information, and are not used extensively to learn about product efficacy.

The importance of drug promotion as a source of drug information can be attributed to its easy availability. However, there is a lack of any alternative source which pro vides all the drug information that doctors would like to have easily available. Drug promotion does not appear to fulfil the information needs of the prescribing doctor.

Drug advertising in medical journals

One hundred different drug advertisements from each of seven leading medical journals have been assessed. Information about drug interactions, adverse reactions, mode of action, absorption, distribution, metabolism, excretion and cost was seldom provided in UK journals. A requirement should exist that drug advertisements include such clinically important information. Only a few pharmaceutical companies are attempting to educate doctors through their marketing and promotional material in advertisements in medical journals.

Patient Age as a Factor in Drug Prescribing Practices

Cette étude, qui repose sur les données tirées du sondage national effectué aux Etats-Unis en 1985 sur les soins médicaux ambulatoires, examine le rapport entre l'âge du patient et la prescription de médicaments, mesurée selon la nature inappropriée des ordonnances et leur volume. On a substitué l'expression “ordonnance potentiellement indésirable” à l'expression “ordonnance inappropriée” parce que le fait de disposer de renseignements d'ordre médico-social limités sur le patient, et done d'une connaissance insuffisante de ses antécédents risque, au moment de prescrire un médicament, de rendre le jugement indûment simplifié et critique. Les catégories suivantes ont été établies en ce qui concerne la prescription potentiellement indésirable: 1) plus d'un médicament appartenant à la même catégorie, 2) des catégories de médicaments à ne pas combiner, 3) des medicaments n'assurant qu'un traitement suboptimal et 4) des médicaments et des diagnostics incompatibles. Sur 67 médicaments génériques represéntant 13 catégories de médicaments étudiées, 242 produits ont été prescrits à un échantillon de 33 574 patients âgés de 45 ans ou plus. On a constaté que l'ordonnance potentiellement indésirable était un problème courant quelle que soit la discipline médicale et le sexe du patient, mais qu'il existait un rapport avec l'âge du patient. La consultation d'un médicin généraliste a un effet défavorable plus marque chez les patients âgés, et il en est de même pour la consultation d'un medecin dans les régions non métropolitaines pour ce groupe de personnes.

[Explanatory variables of avoidable cost produced by not prescribing a cheaper equivalent drug]

OBJECTIVE

To identify the explanatory variables of avoidable cost produced by not prescribing a cheaper equivalent drug.

METHODS

We conducted a cross-sectional study of 1,500 primary care physicians in Galicia (northwest Spain). The sample consisted of 405 primary care physicians. The following independent variables were collected through a postal questionnaire physicians' training and specialty, physicians' perception of the quality of available drug information sources, type of practice, and number of patients. The environmental characteristics of the practice were obtained from secondary sources. Multiple regression models were constructed using as dependent variables two indicators based on unnecessary cost produced by not prescribing cheaper equivalents.

RESULTS

The response rate was 77,4%. No association was found between prescription efficiency and the level of the physician's training, or with the variables of utilization or the quality of commercial and institutional information. The variable of health model was not significant. The only statistically significant variables were the number of identification cards and the percentage of pensioners' identification cards.

CONCLUSIONS

The results of this study suggest that physicians attach little importance to prescription efficiency. Thus, to decrease avoidable cost produced by not prescribing a cheaper equivalent drug, the medical curriculum should be modified to ensure that is contents reflect national health priorities and current resources.

Randomized clinical trial on the use of antispasmodic drugs in barium enema: impact on radiological practice

PURPOSE

To assess the willingness of radiologists to change their practice when the results of a randomized clinical trial (RCT) on the use of antispasmodic drugs in barium enema are presented.

MATERIALS AND METHODS

During the years 1994 and 1995 two postal questionnaires were sent to 481 practicing radiologists who were all members of the Netherlands Society of Radiology. In the first questionnaire the respondents were asked to give the characteristics of their practices in performing daily barium enema. The data from this questionnaire was used as a reference. The second questionnaire was sent to the respondents together with an abstract on the randomized clinical trial supporting the use of antispasmodic drugs in barium enema. We also indicated a preference for Buscopan over Glucagon as the antispasmodic drug. The willingness to change prescription habits was measured by comparing the data of the two questionnaires.

RESULTS

Of 481 practicing radiologists, 312 responded to the first questionnaire and gave information of their prescription habits (response rate 64%). These 312 responders were sent an abstract of the RCT and were asked to fill out a second questionnaire to determine their willingness to change their practice. Two hundred and sixty-seven radiologists responded (response rate 86%). A significant number of 119 (51%) were willing to increase the use of antispasmodic drugs. A significant number of 128 (55%) chose to increase the use of Buscopan, while a significant number of 81 (32%) were willing to decrease the use of Glucagon.

CONCLUSION

Direct exposure to the results of an RCT recommending the use of antispasmodic drugs in barium enema, especially Buscopan, is likely to increase its use by practicing radiologists.

[Advertising of drugs: risk or benefits?]

It is obvious how important is the role of the physicians on drugs consumption. On account of their intermediary in the procurement and consumption of medicines, the prescriber is the main focus of manufacturers' promotional activities aiming at increasing sales and profits although these activities often are disguised as a means of education or information. Many reports have been issued emphasizing the influence of commercial sources upon the prescription. This text reviews two of them -advertisements in medical journals and the representatives- arriving to the conclusion that first ones display informations that are biased and incomplete while the representative in fact acts as a sales agent. The professional sources of information for prescribers are also described being evaluated how far-reaching the sources referred can be.

Social pharmacology: unresolved critical issues

This article describes and analyzes decision-making by patients, physicians, and drug information providers about registered medical drugs. Based on a cognitive psychology perspective, cognitive variables (the individual's mediating system) are assumed to be critical factors determining both patient and physician behavior. The individual's psychological functioning is seen as a continuous reciprocal interaction between behavioral, cognitive, and environmental influences; i.e., an interactional paradigm is applied. The importance of research models including cognitive and situation variables to guide the search for appropriate research methods is stressed. An intensive research strategy with a small sample of respondents will often be necessary. Also, respondents should be asked to describe their reactions to specific medical situations. The drug information sender has to select a set of goals for disseminating information to patients. Among the goals most often selected are: message comprehension, receiver satisfaction, changes in knowledge, attitudes, and drug behavior, as well as health effects. More research is needed on how the patient's mediating system, the actual situation, and the perceived situation steer his search for the use of new drug information. A different set of factors influence the patient's decision to start a medicinal or drug treatment than the factors that influence his decision to continue a treatment. The latter factors include forgetfulness, misunderstandings, and the patient's interpretation of physiological signs. More cognitive-oriented research about drug compliance must be undertaken. In such studies the mediating systems of a group of patients could be considered before and after intervention. There are a great number of types of inappropriate (irrational) prescribing. However, a physician may prescribe rationally in one area but irrationally in another. Face-to-face education of physicians has been shown to be effective in reducing inappropriate prescribing in a number of studies. "Overprescribing" of benzodiazepine has been an issue of intensive professional debate during the last decades. The two groups who criticize and defend the existing use of benzodiazepines build their views on different assumptions about the interaction between mind and brain as well as making different value assumptions regarding the use of a psychotropic drug. There is a need for prescription studies where a cognitive and interactional perspective is combined with an information-processing and a normative perspective. The benzodiazepines dependency problem has provoked lively discussion among professionals and the general public. Long-term benzodiazepine use and personality disorders increase the risk of the patient becoming dependent. A great number of research models have been suggested for the analysis of prescription drug dependency and as guides to the treatment of dependency.(ABSTRACT TRUNCATED AT 400 WORDS)

Patterns of preference for information sources in the adoption of new drugs by specialists

The present study investigated the adoption of new prescription drugs by specialists who treat serious disorders using relatively high risk drugs with potentially serious side effects. One-hundred and fifty-six specialists, primarily practicing in medical specialties, evaluated a number of drug information sources and reported their use of these sources both in their general drug adoption procedures and in the adoption of one of a number of target drugs. As predicted, the pattern of drug adoption among specialists is substantially different from that generally reported in earlier studies, which are usually based on samples of general practitioners or of general practitioners and specialists combined. Professional sources of information predominate throughout the process, both in adoption procedures generally used and in the adoption of target drugs. The majority of specialists reported contact with commercial sources at some stage in the adoption process for the target drugs, but these sources were not, as is often reported in the literature, the main sources of first news of a new drug, nor did they exert much influence at the prescribing stage. It is clear from these results that in future research on drug innovation, different classes of medical practitioners, such as specialists vs general practitioners, will need to be distinguished.

Doctors and detailers: therapeutic education or pharmaceutical promotion?

Pharmaceutical companies in industrialized countries generally view detailers as the most crucial element in the promotion of their products, with the result that over 50 percent of expenditures on promotion are devoted to detailers. Publicly the companies make claims for the scientific knowledge of detailers and for their role in passing on information to physicians, but the main purpose of detailers is to sell their company's products. This emphasis on sales is evident from statements of detailers themselves, from advertisements for detailers, from company documents, and by looking at the groups of physicians that companies specially target for visits by detailers. A variety of explanations are offered as to why physicians see detailers, but on examination none of the reasons is justifiable. Studies from a number of industrialized countries have shown that over 90 percent of physicians see detailers and a substantial percentage rely heavily on detailers as sources of information about therapeutics. Detailers are highly successful in altering physicians' prescribing habits, but almost all the literature available shows that the more reliant doctors are on commercial sources of information, the less appropriate they are as prescribers. Widespread use of DES (diethylstilbestrol) and the Dalkon Shield was encouraged by detailers. Although detailers have received the endorsement of both physicians' groups and government bodies, seeing detailers is detrimental to the practice of good medicine, and the best interests of doctors and their patients would be served if physicians had nothing further to do with detailers.

Canadian Psychiatric Association guidelines in relating to the pharmaceutical industry

This paper was prepared for the Professional Standards and Practice Council, then chaired by Dr. Nady el-Guebaly and now chaired by Dr. Werner Pankratz, and approved in principle by the Board of Directors of the Canadian Psychiatric Association in October 1984. Final approval by the Executive on May 21st, 1986.

Differences among practitioners in patterns of preference for information sources in the adoption of new drugs

The major aim of this study was to identify coherent patterns in doctors' preferences for potential sources of information about new drugs and the characteristics of the doctors who display them. One hundred twenty-four general practitioners and specialists evaluated and reported their use of a number of potential sources. Overall, commercial sources were cited more often than professional ones for providing first information about a new drug, but the reverse was the case when the doctor was actively considering prescribing it. The primary professional sources received more favourable evaluation than any of the commercial sources, but results suggest that usage does not necessarily follow the doctor's opinion of a source. Relationships between reported use and evaluation reveal two coherent patterns of source preference: 'journal' and 'commercial'. The commercial pattern is particularly sharply defined, identifying a subset of doctors who can be designated justifiably as 'commercially-oriented'. Evaluation and use of particular sources varied with age and differed between specialists and general practitioners. Results indicate that differences in patterns of preference are systematically related to characteristics of the doctor in combination with the stage of the adoption process.

Hypoglycemic therapy in patients diagnosed to have diabetes at 30 years of age or older

Treatment patterns were investigated for a population of diabetic persons diagnosed at 30 years of age or older who received primary medical care in an eleven county area in southern Wisconsin. Of the 6074 patients who met the diagnostic criteria for diabetes, 51% received their primary care from internists, 35% from general practitioners, and 14% from family practitioners. Insulin usage was more frequent in patients with a longer duration of diabetes, younger age at diagnosis and poor recent glucose control. Prescription of oral medications increased with increasing current age and age at diagnosis. A greater proportion of the patients of internists than those of general practitioners were treated with insulin. Oral hypoglycemic agents were prescribed more frequently for patients of general practitioners than for patients of internists. These differences remained after controlling for duration, age at diagnosis, and status of recent glucose control. Therefore, practitioner type is associated with treatment prescribed for diabetic patients diagnosed after 30 years of age.

Hospital consultants--an influence on G.P. prescribing? A pilot study

Ten thousand National Health Service prescriptions for drugs used in rheumatology, written by 300 general medical practitioners within one Area Health Authority area during one month were analysed. Thirty-six different preparations were prescribed. The prescriptions of three consultants in rheumatology from before the sample period were also analysed. Prescribing patterns were compared, in particular between G.P.s and the consultant to whom the G.P. usually referred his 'rheumatology' patients. Although the correlation coefficients between each consultant and each doctor-group studied were not found to be significant at the 5% level, implying little if any influence by the consultant on the prescribing of these G.P.s, a number of interesting features were noted which seem worthy of further study.

Factors influencing drug prescribing--inquiry into research strategy

This review analyzes the approaches used in published studies into doctors' prescribing habits. Sixty-four studies in English, Scandinavian languages, and Finnish, mainly from the last 15 years, are included. Some factors affecting prescribing have not been studied and there were very few studies into two potentially important factors, education and control measures. Studies which measured the effect of drug firms tend to concentrate on the conventional forms of advertising. The general limitations of each of the approaches are listed and those which seem unlikely to yield much new information are pointed out. Some novel approaches are proposed.

covering the last 15 years were searched systematically, but journals in other fields were not covered so systematically. Some earlier studies were also included. Some studies of possible importance were unobtainable.

Only those studies were included in which the objective was to determine which factors affect, or to what extent they affect, drug prescribing. Studies designed to determine physicians' opinions on the different sources of drug information were. also included. The latter, in some studies, enlarged upon their initial objective. Articles which included descriptions of drug-firms were excluded if the authors had not connected them to drug prescribing. Studies which described prescribing as such were not included.

Only studies into “non-medical” factors were included. Studies into the effects of the results of medical research or the character of disease or the result of the treatment were ignored. So were studies into the “non-medical” properties of a drug, because the drug is here considered as the object of a doctor's decision making and not as an influencer.

Studies into the process of drug adaptation (the mechanism of a doctor's decision making) were largely disregarded. But studies into the effect of a physician's personal characteristics on his prescribing habits were included because these characteristics are an important modifier of the exterior influencers.

The studies were classified according to their most significant factor. The model for classification, described in a previous paper,4 was constructed for developed Western countries. It omits some factors, such as the