Relationship of the nine most commonly advertised drugs to drug memory of the first year residents at King Chulalongkorn Memorial Hospital: a cross-sectional analytical study by questionnaire.

Abstract

Background : There are several studies about the effect of the pharmaceutical company advertisements. In Thailand, although there are data about physicians’ opinions of drug advertisement on prescribing decisions, there is no data representing physicians’memory on drugs and there prescribing that actually happen.

Objective : To compare the memory ability of trade and generic names between of the most advertised drugs and non-advertised drugs, among general practitioners.

Materials and Methods : This is designed as a cross-sectional analytical study. One hundred and forty participants are randomly selected from the first year residents in training at King Chulalongkorn Memorial Hospital to be representatives of the general practitioner. Each is interviewed by using two-part questionnaire: the first part is on the characteristic data, and the second part is on the recognition about the trade name and generic name of two drug groups consisted of thirty-six questions. Eighteen questions are matching of the generic and trade names of the nine most advertised drugs, and the other eighteen questions are about nine non-advertised drugs. This includes the actual prescription of each the drugs used under generic or trade names.

Results : One hundred and three first year residents in training were recruited into the study. Thirty-seven were excluded under the exclusion criteria (5 did not have any experience in real community,: 26 previously studied in specific wards,: 3 were not willing to participate in the research,: 3 are not in the residency program). Among the nine most commonly advertised drugs, the mean difference between the number of correct answers (known both generic and trade name groups) and incorrect answers (known only trade name group) is –1.74 ± 3.67. In contrast, among the nine non-advertised drugs, it is 3.50 ± 3.78. The mean difference of advertised group and non-advertised group is – 5.24 ± 3.67 (p <0.001). The percentage of participants who gave the correct name more than incorrect answers in the advertised group that is superior to non-advertised group is only 5%. The percentage of participants who gave the correct answers more than incorrect answers in non-advertised group that is superior to advertised group is 93%. The difference is statistically significant (p <0.001). Therefore, the advertisement influences the memorizing of only the trade names. In subgroup analysis, using univariable analysis, factors affecting physicians’drug memory were bachelor’s degree in medicine from Chulalongkorn University, no experience of practice in private hospital and the number of Wongkarnpat’s journals that read in the last year. Although, using multivariable analysis, only the bachelor’s degree in medicine from Chulalongkorn University was statistically significant (p = 0.006).

Conclusion : Advertisement associates general practitioners’drug memory especially only the trade names.