SUPPORT Summaries
Evidence of the effects of health system interventions
for low- and middle-income countries
Evidence of the effects of health system interventions
for low- and middle-income countries
December, 2010 - SUPPORT Summary of a systematic review | print this article |
Direct to consumer advertising is increasingly used by the pharmaceutical industry and its merits have been extensively debated. Regulations related to such advertising vary: in New Zealand and the United States of America (USA), for example, regulations do not explicitly prohibit such advertising and its use has grown. In other countries, however, the practice has been banned and heavy lobbying by the pharmaceutical industry has been resisted.
- The value of policies that allow for the increased use of direct to consumer advertising is uncertain at best; and
- Rigorous monitoring and evaluation are warranted when such policies are implemented
People making decisions concerning the regulation of direct to consumer advertising.
Gilbody S, Wilson P, Watt I. Benefits and harms of direct to consumer advertising: a systematic review. Qual Saf Health Care 2005;14:246-50. See in PubMed
A summary of studies addressing a clearly formulated question that uses systematic and explicit methods to identify, select, and critically appraise the relevant research, and to collect and analyse data from the included studies.
SUPPORT – was an international project to support the use of policy relevant reviews and trials to inform decisions about maternal and child health in low- and middle-income countries, funded by the European Commission (FP6) and the Canadian Institutes of Health Research.
The promotion of prescription-only medicines using direct to consumer advertising is used increasingly by the pharmaceutical industry. Proponents of direct to consumer advertising argue that it increases the use of effective treatments for under-treated conditions. Opponents, however, suggest that it drives up demand for newer, higher-cost drugs that may have marginal benefits and unknown safety profiles.
This summary is based on a review published in 2005 by Gilbody and colleagues, on the effects of direct to consumer advertising.
| Review Objectives: To examine the benefits and harms of direct to consumer advertising of prescription-only medicines | ||
| / | What the review authors searched for | What the review authors found |
|---|---|---|
| Interventions | Randomised controlled trials, controlled clinical trials, controlled before-and-after studies, interrupted time series analyses, and cross-sectional studies with a control group |
3 interrupted time series analyses, 1 comparative cross sectional survey |
| Participants | Not pre-specified |
Patients and physicians in primary care (4 studies) |
| Settings | Not pre-specified |
USA (2 studies), USA and Canada (1), Netherlands (1) |
| Outcomes | Health seeking behaviours of patients at the point of access to care; requests for prescription only medicines; patient-doctor communication and satisfaction with care; prescribing patterns; costs |
Requests for prescription only medicines (4 studies); prescription volume (4 studies); patient-doctor communication and satisfaction with care (1 study) |
| Date of most recent search: October 2004 | ||
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Limitations: A good quality systematic review with only minor limitations |
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Gilbody S, Wilson P, Watt I. Benefits and harms of direct to consumer advertising: a systematic review. Qual Saf Health Care 2005;14:246-50. See in PubMed
High: This research provides a very good indication of the likely effect. The likelihood that the effect will be substantially different† is low.
Moderate: This research provides a good indication of the likely effect. The likelihood that effect will be substantially different† is moderate.
Low: This research provides some indication of the likely effect. Howevver, the likelihood that it will be substantially different† is high.
Very low: This research does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different† is very high.
* This is sometimes referred to as 'quality of evidence' or 'confidence in the estimate'.
† Substantially different = a large enough difference that it might affect a decision.
See last page for more information.
The review identified 2,853 publications from which 6 publications (of 4 studies) met the inclusion criteria. Three studies were interrupted time series: of these, 2 were conducted in the USA and 1 in the Netherlands. The fourth study was a cross-sectional survey comparing the impact of direct to consumer advertising in the USA and Canada.
A synthesis of the four studies showed that:
Direct to consumer advertising |
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| Patient or population: Patients and clinicians Settings: Primary care in USA (2), USA and Canada (1), and Netherlands (1) Intervention: Direct to consumer advertising Comparison: No intervention |
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| Outcomes | Impact |
Number of participants |
Quality of the evidence (GRADE) |
|
Prescriptions
Prescriptions |
DTCA was consistently associated with increased numbers of patient requests and/or increased prescription volume for the advertised medicines |
(4 studies) |
Grade Quality=High] |
| Health outcomes |
No studies examined the impact of DTCA on patient satis-faction with care, or the impact of DTCA and altered pre-scribing on actual health outcomes |
[0] (No study) |
|
|
Costs |
No studies examined the cost effectiveness of DTCA by combining health outcomes, or the economic costs of al-tered prescribing |
[0] (No study) |
|
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GRADE: GRADE Working Group grades of evidence (see above and last page) |
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| Findings | Interpretation* |
|---|---|
| APPLICABILITY | |
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| EQUITY | |
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| ECONOMIC CONSIDERATIONS | |
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| MONITORING & EVALUATION | |
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*Judgements made by the authors of this summary, not necessarily those of the review authors, based on the findings of the review and consultation with researchers and policymakers in low- and middle-income countries. For additional details about how these judgements were made see: http://www.support-collaboration.org/summaries/methods.htm |
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Related literature
Frosch DL, Grande D, Tarn DM, Kravitz RL. A decade of controversy: bal-ancing policy with evidence in the regulation of prescription drug advertising. Am J Public Health 2010;100:24-32.
Mintzes B, Morgan S, Wright JM. Twelve years' experience with direct-to-consumer advertising of prescription drugs in Canada: a cautionary tale. PLoS One 2009;4(5):e5699.
Atherly A, Rubin PH. The cost-effectiveness of direct-to-consumer advertising for prescription drugs. Med Care Res Rev 2009;66:639-57.
Norey E, Simone TM, Mousa SA. The impact of direct-to-consumer adver-tised drugs on drug sales in the US and New Zealand. Appl Health Econ Health Policy 2008;6:93-102.
Law MR, Majumdar SR, Soumerai SB. Effect of illicit direct to consumer advertising on use of etanercept, mometasone, and tegaserod in Canada: controlled longitudinal study. BMJ 2008;337:a1055.
Hoffman JR, Wilkes M. Direct to consumer advertising of prescription drugs.BMJ 1999;318:1301–2
Mintzes B. Direct-to-consumer advertising of prescription drugs in Canada. What are the public health implications? Health Council of Canada. January 2006.
This summary was prepared by
Charles Shey Wiysonge, School of Child and Adolescent Health, University of Cape Town, Cape Town, South Africa
Conflict of interest
None. For details, see: Conflicts of Interest
Acknowledgements
This summary has been peer reviewed by: Simon Gilbody, UK; Joel Lexchin, Canada
This summary should be cited as
Wiysonge CS. What are the benefits and harms of direct to consumer advertis-ing? A SUPPORT Summary of a systematic review. December 2010.
This summary was prepared with additional support from:
The University of Cape Town (UCT), South Africa. UCT aspires to become a premier aca-demic meeting point between South Africa, the rest of Africa, and the world. Taking advantage of expanding global networks and our distinct vantage point in Africa, we are committed, through innovative research and scholarship, to grapple with the key issues of our natural and social worlds.
www.uct.ac.za
