'At-risk' individuals' responses to direct to consumer advertising of prescription drugs: a nationally representative cross-sectional study

Neda Khalil Zadeh, Kirsten Robertson, James A Green
2017 BMJ Open  
Word count (abstract)/limit: 298/300 words Word count (text)/limit: 2990/4000 words without title page, abstract, tables, and references ABSTRACT Objectives: The factors determining individuals' behavioural responses to direct to consumer advertising of prescription medicines were explored with an emphasis on 'at risk' individuals' responses. Design: Nationally representative cross-sectional survey. Setting: Community living adults in New Zealand. Participants: 2057 adults (51% female). Primary
more » ... outcome measures: Behavioural responses to medicine advertising (asking a doctor for a prescription, asking a doctor for more information about an illness, asking a pharmacist for more information about the advertised medicine and searching the Internet for more information regarding an illness) Methods: Multivariate logistic regressions were employed to determine whether participants' behavioural responses to medicine advertising were predicted by attitudes towards advertising and pharmaceutical advertising, judgements about safety and effectiveness of advertised medicines, health status, materialism, online search behaviour, as well as demographics. Results: Poorer health, favourable attitude towards medicine advertising, and using the Internet to search for medical information were predictors of all behavioural outcomes. A lower level of education was a predictor of asking a doctor for a prescription. Older age was associated with seeking more information from a doctor or pharmacist. A lower level of income was a predictor of all behavioural responses except for searching the internet. Respondents' ethnicity also influenced the behavioural responses to medicine advertising. A higher level of materialism was a predictor of all behavioural outcomes except for asking a pharmacist for more information, and thus these ads may be appealing to individuals' consumerism rather than purely providing information regarding medicines. Conclusions: Taken together, these findings suggest individuals, especially who are 'at risk' (i.e. with poorer health status, lower education, and lower income) may make uninformed decisions. The outcomes raise significant concerns relating to the ethicality of medicine advertising and suggest a need for stricter guidelines to ensure that medicine advertisements provided by pharmaceutical companies are ethical. medicine advertising; Structural influence model of health communication; 'At risk' individuals ARTICLE SUMMARY Strengths and limitations of this study • A strength of this study is the use of large and representative sample, so that the findings can be generalized to national population in New Zealand. • This is the first study to explore the factors determining individuals' behavioural responses to direct to consumer advertising of prescription medicines in New Zealand and at a population level. • This is the first study to explore the relationship between materialism and responding to medicines advertising. • The cross-sectional study does not explore the causal relationships between dependent and independent variables. whether 'at risk' individuals (older, less educated, with lower income, lower occupational status, and poorer health) were more likely to be influenced by this advertising. Research has also focused on the role of other personal characteristics in determining responses to advertising. Positive attitudes towards medicine advertising predict behavioural intentions and responses to such advertising. 30-32 Materialism is associated with purchasing behaviour in general and lower psychological well-being, 33 but no previous research has explored the influence of being materialistic on the response to medicine advertising. People are increasingly searching for medical information on the Internet 34 but this may differ by education, income, and ethnicity. These inequalities in Internet usage may intensify health inequalities among different groups. [35][36] [37] Therefore, this study also examined the influence of attitude, being materialistic, and use of the Internet to search for medical information on behavioural responses to medicine advertising. METHODS Source of Data This study analysed a subset of pharmaceutical and health-related questions from a large online survey covering a range of attitudes, behaviour, consumption, and lifestyle questions. Data collection was performed in late 2013 by an Australasian market research company. Quota sampling was used for selecting the survey participants. The instructions were that the respondents were to be over 18 and demographically representative of the New Zealand population in terms of age, sex, education, ethnicity, and income. 2057 usable responses were retained for analysis. Since an independent panel survey was used, it was not possible to calculate a response rate (participants were signed up to complete the surveys that were sent). This study had ethics approval from the University of Otago, and all participants gave their written consent. Data Analysis Data was analysed with IBM SPSS Statistics for Windows, Version 22.0, Armonk, NY: IBM Corp. Descriptive statistics were used to calculate frequencies, mean, and standard deviation of items. Omega and alpha estimates of reliability were calculated using the 'MBESS' package in R. Multivariate binary logistic regression models were used to show how strongly independent variables were associated with behavioural responses to DTCA, and subsequently to reveal the factors determining behavioural outcomes. The association between each independent and dependent variable was examined using odds ratios (ORs). The statistical significance of each coefficient in the model was defined by the 95% confidence interval (CI). Predictive accuracy and overall appropriateness of the models were examined by non-significant (p > 0.05) Hosmer-Lemeshow tests (Hosmer et al., 2013) 45 and significant (p < 0.01) Omnibus test of model coefficients. RESULTS Sample characteristics The demographics of the sample are presented in Table 1 . Table 2 shows the means and standard deviations for non-demographic independent variables. 60% of respondents considered themselves in good health. 5.2% were completely satisfied with their overall health, 25% were dissatisfied, and only 3.4% were completely dissatisfied with their overall health. 48% had looked for medical information online. Almost a third of the sample (30.7%) believed that DTCA was helpful for consumers, 43.7% thought that only medicines that are completely safe could be advertised, and 35.3% believed that only medicines that are extremely effective could be advertised. Moreover, as a result of seeing DTCA, 11.4% of participants asked their physicians for a prescription, 15.9% asked their physicians for more
doi:10.1136/bmjopen-2017-017865 pmid:29217723 pmcid:PMC5728274 fatcat:j4zn2viojngojpqz3acj7rgrei