Introduction

In the late 20th century the US Food and Drug Administration (FDA) issued a new guidance for broadcast advertising of prescription drugs directly to consumers (Food and Drug Administration, 1999; Kornfield et al., 2015). According to FDA regulations, prescription drug ads cannot be false or misleading or omit facts that are material to representations made in the ad, and they must have “fair balance” in how the ads present risk and benefit information (Baylor-Henry & Drezin, 1998; US General Accounting Office, 2002). The regulations differ somewhat for advertisements in various channels. For direct-to-consumer advertising (DTCA) in print formats, the ad must include information in “brief summary” about side effects, contraindications, and effectiveness, often resulting in a detailed section presenting this information that is visually set off from the main body of the ad (Kaphingst, Rudd, DeJong, & Daltroy, 2004; Kessler & Pines, 1990). For broadcast DTCA, advertisements that mention the name and use of a specific prescription drug and include claims about efficacy and safety (called product-specific ads) must include a “major statement” of the main adverse effects and contraindications (Bradley & Zito, 1997; Food and Drug Administration, 1999). Broadcast DTC ads must also include either the brief summary or “adequate provision” for dissemination of the approved product labeling for that prescription drug (Bradley & Zito, 1997; Nordenberg, 1998).

In their guidance, the FDA suggested that broadcast DTC ads could meet the adequate provision requirement by referring consumers to physicians and pharmacists and to more detailed product information available through a website, toll-free telephone number, and a concurrently running DTC print ad (Food and Drug Administration, 1999; Talley, 1997). Because of the time requirements of a broadcast ad, ads generally have relied on this adequate provision requirement rather than including an entire brief summary. These regulatory changes led to a massive increase in direct-to-consumer advertising (DTCA) of prescription drugs, from $985 million in 1996 to $4.3 billion in 2010 (Arnold & Oakley, 2013).

DTCA comprises a relatively small proportion of total spending on promotion of prescription drugs, less than 20% of total spending between 2001 and 2010 (Donohue, Cevasco, & Rosenthal, 2007; Kornfield, Donohue, Berndt, & Alexander, 2013). Despite this, DTCA has been shown to have an impact on health-care utilization (Frosch, Grande, Tarn, & Kravitz, 2010), including increases in physician visits and requests for prescription drugs (Gellad & Lyles, 2007; Myers, Royne, & Deitz, 2011). DTCA may also affect physician prescribing practices and drug prices, although results from prior research to examine these issues have been somewhat inconsistent (Calfee, Winston, & Stempski, 2002; Capella, Taylor, Campbell, & Longwell, 2009; Donohue, Berndt, Rosenthal, Epstein, & Frank, 2004; Kalyanaram & Phelan, 2011; Kornfield et al., 2015). In a previous study, a time series analysis showed that for every million dollars spent on DTCA for a particular type of prescription drug (i.e., aromatase inhibitors), there was an associated 0.15% increase three months later in the proportion of new prescriptions for that drug (Abel et al., 2013).

While the majority of DTCA has been conducted via television, print has also been an important medium for this advertising, with relatively little use of Internet (Kornfield et al., 2013). Recent studies indicate that DTCA exposure may have peaked in about 2006 or 2007 (Arnold & Oakley, 2013; Kornfield et al., 2015; Kornfield et al., 2013), and that use of this type of advertising on television may be lower as consumers increasingly use online media channels (Kornfield et al., 2015; Liang & Mackey, 2011a; Liang & Mackey, 2011b). Despite these trends, exposure to DTCA is still quite common in US households, and this advertising continues to be an important source of information about prescription drugs. One estimate based on 2011 data was that households in the United States viewed an average of 111 television direct-to-consumer (DTC) advertisements each month (Kornfield et al., 2015). Strikingly, the scope of the DTCA phenomenon is almost unique to the U.S.; no other industrialized nation, with the exception of New Zealand, permits television advertisements for branded prescription drugs (Brouneus, Macleod, Maclennan, Parkin, & Paul, 2012). Liang and Mackey (2011a) have noted that online DTCA may reach consumers in countries where DTCA is not permitted. However, because research on DTCA conducted in countries outside of the United States is quite limited, this chapter will focus on research conducted in the United States.

DTCA has been controversial and hotly debated in the years since the changes in FDA interpretation of the relevant regulations (Frosch et al., 2010). As shown in Table 1, supporters of DTCA have argued that this advertising helps educate and empower consumers, allowing them to be active participants in their own health care, a critical aspect of trends in medicine toward a patient-centered care system (Deshpande, Menon, Perri, & Zinkhan, 2004; Rubin, 2001). Supporters have also argued that DTCA provides the necessary tools to enhance communication between providers and patients (Kontos & Viswanath, 2011). Critics of DTCA have responded that the promotional interests of the pharmaceutical industry might not correspond with the best interests of patients (Kontos & Viswanath, 2011). Critics have also argued that since the main goals of DTCA are building brand recognition and influencing purchasing behavior, the advertisements have limited educational value and the information presented is often not balanced between risks and benefits (Frosch, Krueger, Hornik, Cronholm, & Barg, 2007; Kaphingst & DeJong, 2004; Williams-Jones, 2006).

Health and risk communication research can inform many of these controversial issues, assisting physicians, policymakers, and the public in understanding how consumers respond to DTCA. In the case of DTCA, how the information is presented in the ads is heavily shaped by existing regulations. For example, as described above, prescription drug ads must have fair balance in the presentation of risk and benefit information (Baylor-Henry & Drezin, 1998; US General Accounting Office, 2002). In addition, print DTCA must include brief summary information about side effects, contraindications, and effectiveness (Kaphingst, Rudd, DeJong, & Daltroy, 2004; Kessler & Pines, 1990), and broadcast DTCA that is product-specific must include a major statement of the main adverse effects and contraindications (Bradley & Zito, 1997; Food and Drug Administration, 1999) and either the brief summary or adequate provision for dissemination of the approved product labeling (Bradley & Zito, 1997; Nordenberg, 1998). Therefore, broadcast ads with incomplete risk information were allowed under FDA guidance if the ads met the adequate provision requirement (Kaphingst & DeJong, 2004). For these reasons, it is important to consider how consumers process DTCA presented in different channels, since the different types of DTC ads—particularly broadcast and print ads—are explicitly linked by regulatory guidance.

Because of the ubiquitous nature of DTCA in the United States, it is critical to understand how consumers process the information from the advertisements and the effects on their perceptions, attitudes, and behaviors. This article will focus on prior research that has examined four major topics: (1) the content of DTCA in different channels; (2) consumers’ perceptions of and responses to DTCA; (3) individual-level factors that affect how consumers respond to DTCA; and (4) message factors that impact consumers’ responses. The article concludes with a discussion of the state of the prior literature and will identify gaps in the research to address in future studies.

Content of Direct-to-Consumer Advertisements

A number of prior content analyses have examined the information presented in broadcast and print DTCA. This section will describe the findings from studies that illustrate key content features of DTCA in these channels. Kaphingst, DeJong, Rudd, and Daltroy (2004) conducted a descriptive content analysis of 23 product-specific television DTC ads that examined content features based on McGuire’s communication/persuasion matrix (McGuire, 1985, 1989). Some of the key findings from this study were that benefits information was presented more slowly than risk information, giving consumers more time to absorb facts about benefits than facts about risks. The risk information was generally (83% of ads) presented in one continuous segment, and few ads set off the risk information with a change in speed, tone, volume, or announcer. During the portion of the ad that presented risk information, only positive or neutral visual images were shown, never negative visual images. In terms of the language used to present information, the majority of ads (65%) conveyed information about the severity and frequency of side effects in qualitative terms (57%); few (4%) described the frequency of side effects in quantitative terms. Only text was used to refer to the additional sources of product information (i.e., website, print DTC ad, toll-free number) required to meet the adequate provision requirement.

In a follow-up study, Kaphingst et al. (2004) also conducted an analysis of the supplemental print sources of information to which the 23 television ads referred. For each television DTC ad, they assessed the associated website, magazine DTC ad, and brochure obtained by calling a toll-free telephone number. For all materials, the brief summary section containing information about side effects, contraindications, and effectiveness was assessed separately from the main body of the magazine ad, website, or brochure. The study showed that all of the materials except one had reading grade levels for both the main body section and the brief summary section that exceeded the maximum eighth-grade reading level recommended for materials used with the general public (Root & Stableford, 1999). The results further showed that a college-level reading ability would be needed to read the average brief summary section.

In a separate study focused on print DTCA, Ju and Park (2015) conducted a theory-based content analysis of magazine DTCA based on Taylor’s communication strategy wheel (Taylor, 1999), which organizes the types of appeals used in advertising into six categories. The content analysis found that most DTCA uses a combination of informational and transformational message themes and creative approaches, that DTCA message themes were associated with creative strategies in alignment with Taylor’s six-segment message strategy wheel framework (Taylor, 1999), and that message themes and creative strategies varied across therapeutic categories and DTCA categories with different levels of ad spending. These findings therefore suggested that DTCA is not informational or persuasive but a combination of the two.

Although the Internet is a relatively small component of DTCA (Kornfield et al., 2013), an increasing trend for content analyses of DTCA is to focus on websites or, to a lesser extent, social media. Davis, Cross, and Crowley (2007) investigated the completeness of risk information presented on the pharmaceutical websites of 44 leading prescription drugs advertised directly to consumers. More specifically, as indicators of completeness, they examined whether the following types of risk information were presented: single highest incidence side effect, top three highest incidence side effects, and all side effects with incidence of 10% or greater. The results of the analysis were that, regardless of the specific completeness indicator used, the pharmaceutical websites were unlikely to completely present risk information. The majority (69%) presented information about the single highest incidence side effect on either the home page or an interior page. Just over half (54%) presented the three highest incidence side effects or all top three side effects, and 55% fully reported all side effects with at least 10% incidence. Of note, the analysis also indicated that the greater the number of high incidence side effects, the less likely consumers were to be fully informed of all of the side effects.

In a content analysis study of website DTCA that was focused specifically on stigma, Kang and An (2013) examined whether 88 DTC prescription drug websites for 15 different stigmatized conditions contained stigma-reducing components related to onset controllability (i.e., perceptions of the controllability of the cause of a disease), offset controllability (i.e., perceptions of whether people make an effort to overcome a condition), and recategorization (i.e., combining two groups into one inclusive group). The first two components were based on attribution theory, more specifically, perceptions of controllability (Weiner, 1986). The findings showed that on the homepages of the websites, the three stigma-reducing components were rarely included through either visual or textual cues. On the second-level pages, onset controllability and recategorization were the most prevalent in terms of textual cues, with less frequent inclusion of textual cues for offset controllability components. No visual cues were found on the second-level pages for the stigma-reducing components. In addition, about one-third of the homepages did not contain a direct link to detailed disease information. The authors commented that more balanced educational information is needed in DTCA for stigmatized conditions so that individuals with these conditions are motivated and able to seek out possible treatments.

Tyrawski and DeAndrea (2015) examined DTCA in a relatively new channel: social media. The authors conducted content analyses of: (1) the social media content on the Facebook, Twitter, and YouTube accounts of the top 15 pharmaceutical companies in the world and (2) the content generated by searching on Facebook, Twitter, and YouTube for the top 20 prescription drugs purchased in the United States. The analyses revealed that drug product claims were present in only 2% of social media posts by pharmaceutical companies. A substantial proportion of posts by pharmaceutical companies (41%) were similar to help-seeking DTC ads, in which the availability of treatment for a specific condition is mentioned without a specific product being named. In contrast, in posts related to specific prescription drugs, the majority (69%) contained product claims about the drug; more claims mentioned only benefits (45%) than only risks (27%). About 25% of posts on Twitter and YouTube were presented as personal testimonials. This study showed that while pharmaceutical companies generally do not make product claims about prescription drugs on their social media accounts, these product claims are frequently found while directly searching for the name of a prescription drug and that individuals searching social media for information about specific prescription drugs are much more likely to find benefits information than risk information.

Content analyses of DTCA across channels have generally revealed a lack of balance between presentation of risk information and benefits information, calling into question whether these advertisements are achieving the required fair balance. Important information about risk is often not presented or is presented in language that is too difficult for many consumers to understand. The advertisements combine both informational and persuasive elements, suggesting that these ads cannot be viewed as completely educational. Better balance in the advertisements may help consumers (particularly those with stigmatized conditions) seek more information about treatments, although this is yet to be studied. Interestingly, pharmaceutical companies are less likely to make product claims about prescription drugs than their consumers, and the effects of interactive social media and user-generated content related to prescription drugs have not been examined. In addition, there is a need to examine DTCA across channels. With few exceptions, these studies have focused on DTCA in a single channel. How consumers process and respond to exposure to DTCA in multiple channels has yet to be systematically investigated.

Consumers’ Perceptions of and Responses to DTCA

A major theme in the existing research on DTCA is to examine consumers’ perceptions and attitudes toward this type of advertising, often using data from cross-sectional surveys. In one such study, Beltramini (2006) examined the believability of DTCA among a national sample of 2,563 consumers. About 32% of the survey respondents reported reading or listening to most DTCA; about 46% overall reported that they liked the ads, while only 26% reported that they understood the ads. Overall, respondents did not have strong perceptions that DTCA was believable. Approximately 39% thought that DTCA provided believable information about their current medical condition, 35% about other medical conditions with which they had little experience, and 29% about new prescription drug treatment options. In terms of risk and benefits information, 31% perceived DTCA to provide believable information about risks and side effects and 28% about potential benefits. About 45% thought that the ads gave enough believable information to decide whether the drug was right for them, and 29% that there was enough believable information to discuss with their health-care provider. However, despite the perceived limited believability of DTCA, 52% of respondents reported planning to ask their doctor for a prescription drug based on this advertising.

In another study, Atkin and Beltramini (2007) examined factors that might affect perceptions of an ad’s believability. They found that, among 101 survey respondents, the average believability score across six media (i.e., television, magazine, radio, websites, direct mail, other print) was 3.0 out of 5. This result indicated that respondents had a neutral perception of the believability of DTCA and that respondents neither believed nor disbelieved the advertising overall. Examining differences in perceptions of believability across media, television DTCA was thought to be the most believable of the six media with a mean score of 3.6 on the five-point scale. When asked what factors might affect the believability of DTCA, respondents identified listing the side effects of a drug (70%), the credibility of the pharmaceutical company (60%), and provider recommendation (55%).

Sullivan and Campbell (2015) assessed consumers’ perceptions of DTCA based on survey data collected from a nationally representative sample of nearly 4,000 US adults who responded to the 2011 Health Information National Trends Survey. The findings from the survey revealed that 46% of respondents did not think that DTCA included enough information about the benefits of a drug and 52% did not think that DTCA included enough information about risks. Overall, only 23% of consumers believed that DTCA included enough information about both benefits and risks. Interestingly, these results were similar to the findings from the Health Information National Trends Survey conducted in 2002, suggesting that these perceptions of DTCA have been fairly stable over time. The study also showed that consumers with higher educational attainment and higher income were less likely to agree that DTCA provided them with enough information about the benefits and risks of prescription drugs. In addition, consumers who did not purchase prescription drugs were more likely to agree that DTCA gives them enough information about benefits and risks compared with those who purchased prescription drugs.

Some prior studies have examined consumers’ learning from DTCA using measures of recall or comprehension. Kaphingst, Rudd, DeJong, and Daltroy (2005) directly assessed comprehension of three actual television DTC ads among a sample of 50 adults with limited literacy recruited from adult basic education centers. On average, participants correctly answered 59% of true/false questions assessing their comprehension of the information presented in the advertisements. The study showed that participants were less likely to answer questions about risk information correctly than questions about other types of information. Participants were also less likely to answer a comprehension question correctly if the information was given in text, with or without accompanying audio, rather than in audio only.

A larger body of prior research has examined consumers’ behavioral and health information seeking responses to DTCA, using primarily observational study designs. Lee, Salmon, and Paek (2007) examined nationally representative survey data related to consumers’ responses to DTCA collected from 3,000 adults. This study was based on the consumer socialization theoretical framework, a framework of the processes by which young people acquire skills, knowledge, and attitudes relevant to their functioning as consumers in the marketplace (Moschis & Churchill, 1978). In this framework, individuals’ attitudes and behaviors can be influenced by both personal (cognitive-psychological) and environmental (social stimuli) (Rouse, 1990), often represented by interpersonal and mass-mediated communications. The study found that consumers who relied more on mass media and interpersonal channels for health information formed more positive attitudes toward DTCA advertising. Consumers who relied more on interpersonal channels for health information discussed the advertised drug more with their providers, while those who relied more on mass media for health information did not. In addition, consumers who held more positive attitudes toward DTC advertising were more likely to have discussed an advertised prescription drug with their providers.

In a cancer-focused study, Abel, Burstein, Hevelone, and Weeks (2009) used patient questionnaires to examine awareness of cancer-related DTCA, perceptions of such DTCA, and subsequent behaviors among 348 patients in active treatment for breast and hematologic malignancies. They found higher levels of awareness (86%) of cancer-related DTCA among these patients, most frequently from television DTCA (78%). A majority of the patients had positive perceptions of cancer-related DTCA: 62% thought it increased awareness of other treatments; 65% that it provided information in a balanced way; and 57% that it allowed them to have better discussions with their providers. Each of these perceptions was significantly more favorable toward DTCA among those with lower educational attainment (i.e., less than a college degree). Only 11% thought that cancer-related DTCA made them less confident in their providers’ judgment. Of those with awareness of cancer-related DTCA, a relatively low proportion, about 17%, reported talking with their provider about an advertised medication.

Although many observational studies related to DTCA have relied on cross-sectional survey data collected at a single time point, there are some previous studies that have utilized longitudinal designs. For example, Tan (2014) examined data from colorectal, breast, or prostate cancer patients who were randomly sampled from the Pennsylvania Cancer Registry. Using a longitudinal design, the study showed that exposure to cancer-related DTCA was associated with increased health information seeking. More specifically, exposure to cancer-related DTCA since diagnosis was related to increased levels of subsequent patient-provider information engagement and marginally related to health information seeking from other sources than providers.

Wood and Cronley (2014) examined changes in attitudes and communication with health care providers about DTCA, comparing two rounds of cross-sectional survey data collected in 2003 and 2012. The study revealed changes in attitudes and communication behaviors over this period. More specifically, attitudes toward DTCA were significantly more negative in 2012 compared to 2003. In 2012, consumers reported talking significantly less about the names of advertised prescription drugs, comparing the advertised drug with their current medication and sharing general information than consumers in 2003. In this study, of those who specifically requested a prescription, the proportion of patients who received the prescription was significantly lower in 2012 than in 2003. The authors suggest that these findings indicate that providers and patients may be adjusting their responses to DTCA over time.

The prior research on consumers’ perceptions and responses has therefore indicated that consumers have a neutral or slightly negative view of the believability of DTCA, on average, although perceptions of this advertising may be somewhat more positive in specific patient populations such as cancer patients. In addition, many US adults do not believe that they receive enough information about the benefits and risks of prescription drugs from DTCA, and comprehension of risk information presented in the advertisements may be lower than comprehension of benefits information. Results from prior observational studies have also indicated that exposure to DTCA may impact consumers’ behaviors related to health information seeking and discussions of advertised drugs with providers.

Individual-Level Factors Affecting Responses to Direct-to-Consumer Advertising

Kontos and Viswanath (2011) have highlighted the importance of examining differences in social groups in responses to DTCA (e.g., accessing, seeking, attending, processing, acting on information). This section will describe previous research related to how individual-level factors might affect how consumers respond to DTCA. A number of studies have investigated how age affects responses to this type of advertising. DeLorme, Huh, and Reid (2006) examined age differences in responses to DTCA, more specifically, inquiring about a prescription drug and requesting a prescription drug. The authors conducted a survey of a random sample of adults living in a northeast Georgia metro area, with analyses conducted among those respondents who reported exposure to DTCA relevant to their health within the past six months. The study found that age was generally not predictive of behaviors prompted by DTCA, although older respondents were more likely to talk to a pharmacist than younger age groups. The results of the study did show that consumers were generally more likely to inquire about a prescription drug than to ask for a prescription drug from a provider following exposure to DTCA.

Ball, Manika, and Stout (2016) also examined how age influenced processing of information in DTCA. Their study was based on two theoretical frameworks of how age affects information processing: cognitive theory, which involves loss of abilities with age, and socioemotional selectivity, which involves changes in motivation related to age and time horizon (Brown & Park, 2003). The study design was an online survey of 1,036 members of a web-based panel. The findings indicated that adults aged 50 years or older had greater complexity in their consideration of DTCA than younger adults less than 50 years. The study showed that trust in mediated sources of health information and trust in physicians were more relevant predictors for older adults. In addition, trust in DTCA had an inverse relationship with behavioral intentions related to further information seeking among older adults but a positive association with attention among younger adults. The study also suggested that younger adults are more open to seeking additional information following DTCA exposure but that older adults remain more ambivalent.

Ceccoli and Klotz (2013) examined a number of possible individual-level predictors of consumers’ attitudes toward DTCA using survey data. The findings indicated modest support for DTCA overall, with about 45% of respondents agreeing that the increase in DTCA was a “good thing” or “very good thing.” The analyses also showed a number of individual-level variables that were related to consumers’ attitudes toward DTCA. Those who had looked for health information on the Internet were more likely to view increased DTCA as a good thing. The study also showed that respondents with higher educational attainment and those who were white had more negative attitudes toward DTCA than those with lower educational attainment or who were non-white, respectively. In this study, age, insurance status, and gender were not significantly associated with attitudes toward DTCA. Interestingly, contrary to the authors’ hypothesis, respondents who viewed themselves as the primary health-care decision maker, rather than their doctor, were less favorable toward increased DTCA.

Using both observational and experimental study designs, a number of other studies have examined individual-level factors in addition to sociodemographic variables that impact how consumers process and respond to DTCA,. Ahn, Park, and Haley (2014) examined the effects of two other individual-level factors, optimistic bias (i.e., belief that one is at less risk of experiencing adverse reactions to prescription drugs than one’s peers) and subjective health literacy (i.e., self-reported health-related skills and knowledge), on processing of information presented in DTCA. The authors conducted a survey of a convenience sample of 404 respondents, guided by the Elaboration Likelihood Model and the Motivation-Ability-Opportunity framework (Batra & Ray, 1986; Petty, Barden, & Wheeler, 2002; Petty & Cacioppo, 1986), to examine the roles of individual motivation and ability on processing of risk information presented in DTCA. The study showed that consumers with an optimistic bias were significantly less likely to pay attention to the risk disclosure or intend to seek additional information about a drug’s health risks than those who did not have this optimistic bias. The latter relationship between optimistic bias and information seeking intentions was stronger for consumers with high subjective health literacy than those with low subjective health literacy.

The effect of subjective health literacy on processing of information presented in DTCA was also examined in a separate study of older adults. An and Muturi (2011) conducted in-person interviews of 170 older adults (i.e., aged 66 years and older). They found that that these participants perceived DTCA as having relatively low educational value. For example, only 35% of participants rated DTC ads as good or excellent in terms of information about the condition the drug is designed to treat, 31% for information about potential benefits, 30% for information about potential side effects, 21% for information about contraindications, and 8% for information about directions on how to use the drug. The study also showed that those with low subjective health literacy perceived the educational value of DTCA to be significantly lower than those with high subjective health literacy.

In sum, existing research has examined several individual-level factors that might affect how consumers process and respond to DTCA, including sociodemographic factors, optimistic bias, and subjective health literacy. More specifically, findings from prior studies have indicated that age, educational attainment, optimistic bias, and subjective health literacy may affect processing of DTCA information, although these findings have been somewhat inconsistent in terms of both direction and magnitude of the underlying relationships. Additional research is needed with both experimental and observational designs to clarify how processing and responses to DTCA may differ in population subgroups defined by different individual-level variables.

Message Factors Affecting Responses to Direct-to-Consumer Advertising

In addition to individual-level factors, prior research has examined message factors that affect how consumers process and respond to DTCA, using primarily experimental designs. In one previous study, Jalnawala and Wilkin (2007) conducted an experiment to examine how consumers process information presented in DTCA and form beliefs about medications. The study was based on inoculation theory (i.e., preexposure to counterarguments reduces the effects of subsequent counterarguments) and the theory of belief formation, which has been used to study the influence of argument structure (i.e., data, warrants, claims, backing, qualifiers, rebuttals) on the persuasiveness of an advertising message (McGuire & Demetrios, 1961; Toulmin, 1958). In the study, 263 undergraduate students were randomized to one of four groups to view a print DTC ad that varied on two factors: sidedness of the appeal (one-sided with only positive attributes vs. two-sided with both positive and negative attributes) and type of argument (causal vs. authoritative). After they viewed the ad, the participants were then presented with a negative scenario that they developed the condition (i.e., flu) despite taking the medication. Change in beliefs and intent to inquire about the drug were measured before and after the negative scenario. The study showed that the two-sided appeals resulted in less change in beliefs about the ads and change in intent to inquire about the drug than one-sided appeals, as suggested by inoculation theory. The authors suggested that the fair balance requirement requiring a balance of risk and benefit information in DTCA may actually be beneficial to pharmaceutical marketers since two-sided appeals may increase the strengths of consumers’ beliefs.

A number of prior studies have focused specifically on message factors related to the presentation of quantitative information in DTCA. Ju and Park (2013) conducted two experiments to examine the persuasive effects of presenting quantitative information. In the first experiment, 184 college students were randomly assigned to read a print DTC ad that either used statistical information or broad verbal statements in presenting information on sleep disorder prevalence and a hypothetical drug’s benefits and risks. This experiment found that participants with a low level of numeracy (i.e., number-related quantitative skills) had more favorable perceptions of message effectiveness and attitudes toward the ad for the condition with quantified information than the condition with broad language. The authors then conducted a second experiment with 203 college students randomized to receive one of four print ads designed to manipulate quantification (i.e., statistical information versus broad statements) and framing (i.e., gain versus loss). In this second experiment, the study showed that when an ad used a gain frame (i.e., emphasized positive consequences of taking the drug), the ad with quantitative information was more effective than the ad with broad language; this relationship was not observed when the ad used a loss frame (i.e., focused on the negative consequences of not taking the drug).

Sullivan, O’Donoghue, Aiken, Chowdhury, Moultrie, and Rupert (2016) conducted an experiment to investigate whether visual aids assisted consumers’ recall of quantitative efficacy information in DTCA and what types of visual aids were most helpful. Over 2,500 individuals diagnosed with high cholesterol were randomized to view a hypothetical DTC ad (print or television) that had no visual aid or one of four visual aids (i.e., pie chart, bar chart, table, pictograph). The study showed that, for print ads, a bar chart or table led to more accurate recall of drug efficacy information. For television ads, any of the visual aids was better than no visual aid for recall of drug efficacy information. The study therefore indicated that presenting visual aids that showed quantitative drug efficacy information in both print and television DTCA increased recall of this efficacy information.

O’Donoghue, Sullivan, and Aikin (2014) examined the effect of adding placebo rates to DTCA, to place the rates presented in the ad into context, and framing with two studies. In the first experimental study, 2,000 members of an Internet panel with chronic pain were randomized to view print DTC ads that varied in placebo rate and framing (i.e., single, positive frame versus a mixed frame with both positive information on how many people had better outcomes and negative information on how many people did not have better health outcomes). The results from this study showed that participants who viewed placebo rates could recall them; those who viewed the single positive frame could more accurately recall quantitative information than those who viewed the mixed frame ads. Notably, however, those who saw the single, positive frame perceived the drug as more beneficial than those who saw the mixed frame. In the second study, 596 health-care providers were asked to rank DTC ads that varied in placebo rate and framing according to how well the ads conveyed the information and the perceived usefulness for their patients. In this study, providers preferred an ad with placebo rates and a single frame. The findings indicated that adding information on placebo rates may be helpful for consumers.

A number of other prior studies have focused specifically on the presentation of risk information in DTCA. Wogalter, Shaver, and Kalsher (2014) examined the effect of auditory (voice) or visual (text) presentations of risk information in television DTCA using an experimental design with 180 undergraduate students. Risk disclosures in television ads were digitally altered to include fictitious risk information, so that recall and recognition would be based only on information provided in the study. Participants were randomized to one of the following conditions: no risk disclosure; auditory risk disclosure only, visual risk disclosure only, visual and auditory risk disclosure, visual risk and auditory non-risk disclosure, and auditory risk and visual non-risk disclosure. The study showed that redundant presentations of both visual and auditory modalities led to the highest levels of recall and recognition (p<.001). The visual-only condition performed better than the auditory-only condition. Simultaneous presentation of non-risk information together with risk information led to lower recall and recognition compared to risk disclosures alone.

Aikin, O’Donoghue, Swasy, and Sullivan (2011) conducted an experimental study to examine consumers’ understanding of and preferences for four different formats for the required brief summary section of print DTCA, which contains required risk information. They randomized 300 overweight consumers to receive the following formats: traditional (i.e., plain language version of risk sections from professional labeling); question and answer (i.e., headings framed in the form of questions); highlights (i.e., summary section from revised professional labeling); and prescription drug facts box (i.e., similar to over-the-counter drug facts label). Compared to those who viewed the traditional format, consumers who viewed the drug facts format had better recall of risks. The study also showed that the drug facts format was most preferred, followed by the question-and-answer format, the traditional format, and, lastly, the highlights format. The study concluded that this experiment therefore indicated that the traditional format for the brief summary is not the best understood or most preferred by consumers.

A variety of other message factors have been explored in this literature. Shim, Cappella, and Lerman (2010) assessed the effects of cues in DTCA related to family history as a disease risk factor on consumers’ responses. This experimental study was conducted with 395 adults who were a random sample of US adults aged 18 or older. Participants were randomly assigned to one of two conditions: familial risk or control. In both conditions, the participants viewed three DTC ads and one control ad for an over-the-counter product. The control condition ads were edited to remove any mention of family history or familial risk. The findings showed that familial risk cues in DTCA strengthened both intention to purchase advertised prescription drugs and intention to engage in healthy lifestyles related to physical activity and diet, in part through enhanced self-efficacy related to health habits. The study did not find effects of family history cues on perceived genetic risk for health conditions or belief in genetic determinism. The authors suggested that cues in DTCA about family history as a risk factor can increase behavioral intentions without increasing a sense of fatalism.

O’Donoghue et al. (2014) used an experimental design with fictitious ads to examine the effect of comparative claims in DTCA (i.e., comparing the prescription drug in the ad to another prescription drug, named or unnamed) on consumers’ perceptions and recall. In one experiment with 1,934 participants with osteoarthritis, they found that participants who viewed print ads, but not video ads, with a named competitor had significantly greater perceptions of efficacy and lower perceptions of risk than those who viewed either a noncomparative ad or an ad with an unnamed competitor. In a second experiment with 5,317 participants with high cholesterol or high body mass index, the study found that named competitors led to higher efficacy perceptions than ads with unnamed competitors or noncomparative ads for both print and video ads, and higher perceptions of risk for print ads. The authors suggested that comparative claims in DTC ads could mislead consumers about a drug’s efficacy and risks.

In one previous experimental study based on the limited capacity model of motivated mediated message processing framework (Lang, 2006), Norris, Bailey, Bolls, and Wise (2012) examined the effects of emotional tone and visual complexity on processing of health information in DTCA. The study used a 2 (emotional tone: positive/coactive) by 2 (visual complexity: high/low) by 3 (ad repetition) within-subjects repeated-measures design in which participants viewed three television prescription drug ads within each combination of emotional tone and visual complexity. The participants in the study were university faculty and staff aged 50–75 years of age. The study’s findings indicated that high visual complexity improved recognition and recall and that the ads were not visually complex enough to create a state of cognitive overload (i.e., requesting more resources than participants had available to process the message). Another study finding was that positive emotional tone yielded better recall and recognition than coactive tone. The findings suggested that defensive processing (i.e., purposeful gating out of incoming information) may have resulted from aversive activation due to both negative emotional content in coactive ads and to risk statements. In support of this interpretation, the findings indicated that risk information was least well recognized and recalled when received during coactive messages. The study suggested that a positive tone and a fairly high level of visual complexity might maximize encoding and storage of risk and benefit information in DTCA.

Bhutada, Cook, and Perry (2009) examined the influence of coupons on consumers’ responses to DTCA. They conducted an experimental study with 138 adults over the age of 35 years who were not health-care professionals. The participants were randomized to one of two ads for a fictitious cholesterol-lowering drug: an ad that contained a coupon for a free 30-day supply of the drug or a similar ad without the coupon. The study found that consumers who viewed an ad with a coupon had significantly more favorable ad- and brand-related attitudes, as well as intention to inquire about the drug to their doctor. However, perceived risk of the drug did not differ between coupon conditions. The study also showed that highly involved consumers had significantly more favorable attitudes toward the ad, the brand, and coupon, as well as more favorable drug inquiry intentions, and perceptions about the risks associated with the drug.

One prior study examined the combined effects of two ads: a DTC ad and then a corrective ad that addressed overstatements. In an experimental study with 1,057 participants conducted with fictitious advertisements, Aikin et al. (2015) examined how an advertisement that overpromised the benefits of an asthma drug (i.e., the “violative” ad) followed by a corrective advertisement to address the overstatements in the original ad affected consumers’ perceptions, understanding, and behavioral intentions. Participants were randomized to see only the violative ad that overpromised benefits and understated risks; only the corrective ad; the violative ad and then the corrective ad; or a control ad without benefits and risks information. The study found that overstating the benefits of a drug and omitting claims about risk can affect perceptions of a drug’s efficacy, risks, and benefits, and that these inflated claims increased consumers’ intentions to use the drug. In addition, the results of the study showed that a corrective ad could counteract overstatement about benefits but was less successful in counteracting omission of risk information.

A recent study compared responses to DTCA and advertising of over-the-counter drugs. Lee, King, and Reid (2015) compared consumers’ attitudinal and behavioral responses to DTCA and advertising of over-the-counter drugs based on a conceptual framework they created of the effects of this advertising. The study showed that among consumers who had been exposed to both types of drug advertising, and who had taken both prescription and over-the-counter drugs, participants were exposed to more DTCA than over-the-counter drug advertising. Also their attitudes were significantly more positive toward over-the-counter drug advertising than DTCA and that they engaged in more extensive information searches based on DTCA than over-the-counter drug ads. The study also found that those who reported being exposed to and paying more attention to both types of drug advertising, who took a greater number of over-the-counter drugs, and who were younger were more likely to use a larger number of sources when they searched for additional information about an advertised drug following exposure to DTCA or over-the-counter drug ads. In addition, consumers who were more skeptical of and more positive about DTCA engaged in more extensive information searching following DTCA.

In sum, prior experimental studies have investigated the effects of a variety of message factors on processing of and responses to DTCA, factors including: sidedness of the appeal, type of argument, framing, emotional tone, visual complexity, use of quantitative language, channel in which risk information is presented, use of visual aids, use of placebo rates, format for the print brief summary section, use of family history cues, having a named competitor, and use of coupons. The findings from these studies have suggested that: sidedness of the appeal may affect the strength of consumers’ beliefs; use of visual aids may increase recall of quantitative information; including placebo rates may help consumers; simultaneous, redundant presentations of risk information in both visual and auditory channels may boost recall and recognition; the traditional format for the brief summary may not be best for consumers; use of family history cues can increase behavioral intentions; and use of a positive tone and a fairly high level of visual complexity may increase recall and recognition. Other types of experimental studies have examined the effects of combining two ads (i.e., violative and corrective) and compared DTCA with advertising of over-the-counter drugs. This prior literature therefore has the advantage of having examined the effects of a wide range of possible message factors. However, the number of articles on the effects of any given message factor on a particular response is limited, making it more difficult to develop recommendations for policy or practice based on this empirical literature.

Discussion

Health and risk communication research have much to contribute to the understanding of how information is presented in DTCA and how consumers process and respond to this information. Among the themes that emerged from this literature review was that presentation of risk and benefits information is generally not balanced in DTCA, despite requirements for “fair balance,” likely leading at least in part to the findings from other studies that consumers have less favorable attitudes toward the risk information presented in this advertising and that they do not comprehend it as well as the benefits information. Another theme from the literature is that despite consumers’ generally somewhat negative or neutral perceptions of DTCA, this advertising does seem to affect their health information seeking and communication behaviors (e.g., discussions of advertised drugs with health-care providers). A third major theme is that a wide range of individual-level and message factors may impact how consumers process and respond to DTCA.

The existing literature therefore has some implications for the debate over the proposed advantages and disadvantages of DTCA (see Table 1).

The findings support the concerns that the presentation of risk and benefit information is not balanced in this advertising, and that this limits the potential educational values of the advertising. Experimental studies suggest possible strategies, such as use of visual aids and placebo rates and simultaneous presentations of risk information in both visual and auditory channels, that may assist consumers’ understanding of this information. In addition, the prior work of Mackert (2011) showed that advertising professionals have widely varying degrees of expertise in health literacy, suggesting that encouraging use of health literacy and plain language strategies in this advertising may improve the educational value. The literature reviewed in this chapter also suggests that DTCA may increase health information seeking or discussions with providers related to prescription drugs. These associations may vary across population subgroups, and there is at least some indication that the magnitude of these effects has moderated over time. These findings indicate that additional research on whether different provider-patient relationships are enhanced or diminished by DTCA are warranted.

Overall, however, the ability of researchers to draw general conclusions in this area is somewhat limited by the wide variability in previous research. Many prior studies are not based explicitly on health or risk communication theory, and greater use of theory would enhance both theoretical and empirical implications of future research in this area. Many different methodologies have been used to examine DTCA and its effects, including both observational and experimental designs. Greater use of longitudinal designs might help in understanding the longer-term impact of actual DTCA campaigns. Many different types of samples have been used, including samples of undergraduate students, representative samples of all consumers, and samples of consumers who meet the indications for a particular type of advertised drug. Greater attention to systematic differences in how different subgroups of consumers process and respond to DTCA would benefit the field. Future studies could also delve more deeply into understanding the effects of various message factors among different population subgroups and different health contexts. Although this article focused on consumers’ responses and views, additional research examining perspectives of advertising professionals working on pharmaceutical brands can also enhance the understanding of how message factors are used in DTCA. For example, the work of Ball and Mackert (2013) investigated how emotion is used and perspectives on consumer trust among 22 advertising professionals. Future research could examine how intended use of message factors by advertisers is or is not reflected in consumers’ responses.

This review also identifies a number of specific areas in need of future research to understand the impact of DTCA in the United States. Few studies have examined consumers’ responses to DTCA campaigns that are conducted across media channels, despite, for example, the explicit linking of information about a prescription drug presented in broadcast and print DTC channels through the adequate provision requirement. An interesting area for future research would be to examine how DTCA campaigns across media, including campaign components conducted through newer online and social media channels, impact consumers’ behavioral responses such as seeking information about the advertised drug or requesting the drug from a health-care provider. Research regarding consumers’ responses to DTCA in social media is limited and the understanding of the impact of advertising of prescription drugs would be further advanced by examining responses to user-generated content in addition to content from pharmaceutical marketers. Relatively few studies have examined comprehension of information presented in DTCA, in addition to recall and recognition, and how comprehension may or may not affect information seeking and other behaviors. In addition, few studies have examined how consumers’ responses to DTCA could impact the content of provider-patient discussions about advertised prescription drugs, and this would advance the understanding of how DTCA is impacting providers and the health-care system more generally.

DTCA is an important source of information about prescription drugs in the United States and understanding the effects of both the informational and persuasive elements of this advertising is critical. Because the presentation of information in DTCA is strongly influenced by existing FDA regulations, continuing efforts to understand how these regulations shape consumers’ responses is important to informing future policy and practice. Consumers’ responses, including how they process the information from the advertising, request prescription drugs from providers, and share information about prescription drugs, have an important impact on the effects of this advertising. The fields of health and risk communication can therefore bring theories and methodologies that are essential to better understanding the impact of DTCA.