Preliminary, please do not cite
The Impact of DTC Print and
Television Advertising on
Antidepressant Use
Kosali Simon
Associate Professor
Department of Policy Analysis and Management
Cornell University, and NBER
Coauthors:
Rosemary Avery, Cornell University
Matt Eisenberg, Cornell University
Presentation copyright purchased from Cartoonbank.com
Summary
• Questions:
– 1) How does DTCA affect use of antidepressants?
• Effect on self diagnosis
– 2) Does impact depend on medium (magazines vs. TV)?
– 3) Does impact differ for men vs. women?
– 4) Interactive effect of print and TV ad exposure?
• Data:
– Simmons National Consumer Survey (NCS) 2001-2004, merged
with databases of print and TV advertising.
• Method:
– controls for other determinants (including characteristics used by
marketers in targeting advertising)
• Findings:
1)
2)
3)
4)
Use affected just for women
Self diagnosis affected for men and women
Print and TV exposure both affect use; only print affects self
diagnosis
No interactive effect
Importance of Questions
• Anti-depressants treat a prevalent and serious condition
– Depression affects 15 Million Americans a year
– Depression is #1 cause of disability in US and worldwide
– Women are twice as likely to be diagnosed as depressed as men
• DTC advertising increased heavily following 1997
reinterpretation of advertising regulations
– $ spent increased from <.5B in 1997 to 5 billion in 2005; increase
mostly TV
• Knowing how advertising DTC affects use of medications, &
among whom, important for ongoing debate about regulation of
DTCA
– US & New Zealand only two countries to allow DTCA
– DTCA -induced use potentially good or bad
• Has potential to reach populations in ways that could reduce health disparities,
depression is under treated
• Could lead physicians to over-treat or lead to over diagnosis
Study Design-Data
• Simmons National Consumer Survey (2001-2004,
N=85,188), use of
– antidepressants (past 12 months) of those who suffered from
depression in the last 12 months
– print and TV media
• If read list in past yr; if so, which issues, fractions, of last 4 issues
• viewing for ~400 broadcast & ~400 cable programs (~ 85% all TV ads)
– asked viewing by time slot of a typical weekday and typical weekend
– demographic & SES used by marketers in targeting advertising
• Cornell University archive of print advertising
– All ads in top 26 consumer magazines (represents 57.5% of all
magazine readership)
• Purchased archive of TV ads (TNS Media Intelligence)
– Tells us which ads appeared on which shows at which times in which media
market
Study Design-Method
Y=α+ βAds+δX+ε
Y=self diagnosis, product use
Problem: Ads not exogenously assigned
1)
2)
Marketers place AD ads where & when they are likely to get the most demand response
Individuals who are most severely depressed may both see more ads (because they see more
TV) and use more medications
Solution:
NCS contains the characteristics used by marketers
X includes: f.e. for magazines category, TV programs, intensity of viewing and
readership, age, race, gender, education, household income, region, marital
status, employment characteristics, health insurance status
Variation in exposure comes from very similar people reading two different
magazines of same magazine category (eg Vogue vs People), watching
two different episodes of shows in same category—one happens to contain
more DTCA than the other
Placing Our Study Design in Context
• Studies of impact of DTC have been mostly at national
aggregate level
– Rosenthal et al, 2003, Calfee et al (2002)
• Some use national level DTC and individual level use
– Donohue et al 2004, Iizuka and Jin (2005b)
• Some studies have used market level aggregates rather than
national aggregates
– Wonsinska (2005) , Bradford et al (2006)
• Only one prior published study has examined individual
response to individual exposure (Avery, Kenkel, Lillard,
Mathios, Journal of Political Economy, 2007)
– Our study uses the same study design, but newer data, adds TV
data and focuses on antidepressants market
Results
• Y=α+ β1LowAds + β2HighAds+δX+ε
Results: Effect of Ads on Use of
Antidepressants
Men
Women
Print
TV
Print
TV
Low
High
-0.02
-0.06
-0.12
-0.06
0.03
0.05*
0.10**
0.14**
Notes: “High” means above mean for women/men, “Low” mean above zero but
below mean, omitted is 0 ads
OLS coefficients
*** at p=0.01, ** 0.05, * 0.10
Means: Number of Antidepressant Ads
Print sample N=6,286, TV sample N=4,053
– Results are qualitatively similar
with both in together
– No evidence of interactive effect
last 12 months
Men
Print
Mean
7.7
TV
387.8
Women
Print
16.6
TV
445.6
Results (continued)
Results: Effect of Ads on Self Diagnosis of
Depression
Print
Low
High
N=85,188
TV
0.004
-.0086
.0144***
-0.005
Robustness Checks
• If effects are causal, we should see no impact
from including a measure for irrelevant ads
– When we include statin ads, the main results do
not change much, and statin ads show no effect
• Results are not changed by
– choice of estimation method (OLS/probit/logit)
– specific measure of Ad exposure (log, level,
quadratic)
Caveats
1.
2.
Population: Usage only among those who report being depressed
Exposure:
a)Magazines in our data represents only 57.5% of all readership, our TV ads data
merged into NCS contains only 85% of all ads aired during this time period
– Our exposure measure is an underestimate, but no reason to expect that this is
systematic in ways that would affect results
b)We don’t know that they actually examined the ad or just flipped past it in
magazine, or channel surfed on TV during ads
– This means our measures may be over-estimates of true exposure, no reason to
expect systematic;
3.
Timing: We assume the ads you see during the last 12 months impact
your use of antidepressants during the last 12 months
(Still, a vast improvement over prior data & methods )
4.
Given non clinical nature of study, we cant tell if those whose use
increased ad the ones for whom treatment is beneficial or excessive
Contribution to the Literature
• First study to consider impact of individual
DTC exposure of antidepressant ads on
individual use of medications
• Considers effect of both TV and print
• Robust research design, accounts for targeting