This study was a prospective observational study of doctor-pharmaceutical representatives' encounters. It was conducted from 15/8/07 to 15/4/2009 (20 months). Doctors in primary care settings in Australia and Malaysia, who met pharmaceutical representatives in their regular practice and were practicing at least 25 hours per week during the study period, were invited to participate. This study was approved by the Human Research Ethics Committee of the University of South Australia, the Universiti Sains Malaysia (USM) and the Universiti Kebangsaan Malaysia (UKM).
Doctors were asked to monitor four to ten encounters with pharmaceutical representatives. A doctor-pharmaceutical representative encounter was defined as one meeting between doctor(s) and pharmaceutical representative(s) which happened at the doctor's surgery.
Both one-on-one and group presentations were assessed. The meeting was based on an appointment and had to be longer than one minute. "Corridor" meetings with pharmaceutical representatives were not considered suitable for this study. Doctors were encouraged to see as many pharmaceutical representatives during the study period as usual.
Sample size calculation
La Revue Prescrire, which organised a pharmaceutical representatives' monitoring network in France for 15 years, reported that on average, adverse effects were mentioned in 32% of sales representatives' promotional presentations [27]. In this study, an absolute difference between pharmaceutical sales detailing in Malaysia and Australia of 20% in the availability of information on particular adverse effects was considered a substantive difference. A sample size of 66 encounters per study arm would detect this degree of difference with 80% power at α = 0.05.
In Canada, it has been reported that doctors received a mean of 5.6 visits per month from sales representatives (range 0-28) and a mean of 2.2 products per visit [28]. This study assumed a similar situation in Australia and Malaysia. If doctors recorded information on four presentations, a sample size of 20 doctors per study arm would provide 80 observations. Data collection could be completed within four to five weeks per physician.
Recruitment of general practitioners
Australia
Two mechanisms were employed to recruit doctors in Australia.
Eleven divisions of general practices in different states of Australia contacted general practitioners on our behalf. These organizations are members of the network of Australian Divisions of General Practice and funded by the Australian Government Department of Health and Ageing [29].
Doctors who were Healthy Skepticism [21] subscribers (HSS) were invited to participate in the study and to nominate two doctors who could also be willing to participate. The nominated doctors were also invited to participate. Healthy Skepticism is an international non-profit organisation aiming to improve health by reducing harm from misleading drug promotion [21]. This organisation uses research, education and advocacy to improve drug promotion by the pharmaceutical industry. Healthy Skepticism subscribers have an interest in research on pharmaceutical promotion and were considered more likely to participate in the study.
Malaysia
In Malaysia, primary care treatment to the public is provided by three different types of doctors. These are general practitioners in private clinics, family medicine doctors who are undergoing specialist training in teaching hospitals, and family medicine specialists in teaching hospitals or private clinics. All types of primary care providers were included in this study.
Doctors from family medicine departments in two teaching hospitals in Malaysia, Universiti Sains Malaysia, Kota Bharu (USM), Universiti Kebangsaan Malaysia, Kuala Lumpur (UKM), general practitioners in private practices in Kota Bharu and Kuala Lumpur were invited to participate in this study.
Doctors who agreed to participate were asked to nominate two general practitioners from private practice who could also be willing to participate in this study. The nominated doctors were also invited to participate in the study.
The Malaysian Medical Association (MMA) [30] invited its members in rural and urban areas to participate in the study. MMA is a professional body representing Malaysian doctors, which focuses its activities on enhancing healthcare in Malaysia.
All doctors from the Australian and Malaysian lists were invited to participate in this study by a letter or an email. We invited 3038 doctors in Australia and 819 doctors in Malaysia.
Of 3038 Australian doctors that were invited, 2955 were contacted by general practitioner divisions, 70 by Healthy Skepticism and 13 via nominations from general practitioners. In Malaysia, 119 general practitioners were invited from family medicine departments, while 694 were contacted via MMA and six were invited based on recommendations from general practitioners. A reply letter with a prepaid envelope was attached to the invitation letter. A follow up letter or email was sent if no reply was received within two weeks. In Australia, we posted a brief advertisement in the newsletter provided by the South Australia Divisions of General Practice Inc. to 1738 general practitioners in the divisions.
An information sheet was sent to doctors who had agreed to participate in the study. Participating doctors were asked to provide personal details on gender, age, years in practice, postgraduate qualifications, number of doctors in practice and average number of pharmaceutical representatives met every week. Each doctor was assigned an identifying code. Pharmaceutical representatives were made aware of the study and were asked for consent to participate. Only doctors were allowed to get written consent from pharmaceutical representatives.
Following a pharmaceutical representative's visit, doctors filled out a questionnaire focusing on the main product and claims discussed during the encounter. The main product refers to the product that was approved by the authorities to be marketed and was given most attention by the pharmaceutical representative in a single encounter. Doctors were required to report their own assessment of the prescribing frequency of the products promoted. The questionnaire focused on provision of product information, including indications, adverse effects, precautions, contraindications and the provision of information on the listing of a medicine on the Pharmaceutical Benefit Scheme (PBS), the Australian public insurance scheme [31]. "New medicine" was defined as a medicine that general practitioners believed would be marketed soon or had been marketed recently. "Old medicine" referred to a medicine that general practitioners believed had been marketed for a period of time.
Doctors were asked to keep the completed questionnaires in a secure place and send them to the researchers every two weeks in a prepaid reply envelope. The questionnaire was based for its major part on questionnaires developed in previous studies [4, 7, 32]. The face validity of the questionnaire was assessed by six experts in the field of study and doctors in Australia, Malaysia and Canada. The questionnaire was then modified based on their comments.
Data entry was undertaken using SPSS database version 17.0. Chi-square analysis was used to assess differences in the provision of product information given by pharmaceutical representatives to doctors in Australia and Malaysia. As there were multiple observations for each general practitioner, additional clustered linear regression was conducted with STATA 10 to assess if doctors reported information provided to them differently. The Bonferroni correction for multiple comparisons was applied.