Exploring the Persuasive Effects of a Commercial For a Pharmaceutical Product: the Elderly Vs. Young Adults

ABSTRACT - This paper explores the persuasive effects of different commercials for an analgesic on members of different age groups. Commercial content was manipulated to be either of (a) factual or (b) evaluative. The impact of these two contents was assessed on members of two different age groups: young adults (i.e. people between 20 and 40 years old) and the elderly (i.e. people over 55 years old). Results show that unaided recall is lower amongst the elderly whereas commercials with largely evaluative content result in higher miscomprehension amongst them. As compared to young adults, seniors developed more positive attitudes towards the commercials and generated more positive affective responses towards the product regardless of the commercial content, though their overall attitudes tend to be consistently neutral. Involvement towards the product plays an important mediating role, to such an extent that it blurs the effect of age group on attitude towards the product.

Citation:

Jean Perrien, Jean Roy, Denis Guiot, and Etienne Bastin (1998) ,"Exploring the Persuasive Effects of a Commercial For a Pharmaceutical Product: the Elderly Vs. Young Adults", in NA - Advances in Consumer Research Volume 25, eds. Joseph W. Alba & J. Wesley Hutchinson, Provo, UT : Association for Consumer Research, Pages: 513-517.

Advances in Consumer Research Volume 25, 1998      Pages 513-517

EXPLORING THE PERSUASIVE EFFECTS OF A COMMERCIAL FOR A PHARMACEUTICAL PRODUCT: THE ELDERLY VS. YOUNG ADULTS

Jean Perrien, University of Quebec, Montreal

Jean Roy, University of Quebec, Chicoutimi

Denis Guiot, IUT Paris XII

Etienne Bastin, University of Sherbrooke

ABSTRACT -

This paper explores the persuasive effects of different commercials for an analgesic on members of different age groups. Commercial content was manipulated to be either of (a) factual or (b) evaluative. The impact of these two contents was assessed on members of two different age groups: young adults (i.e. people between 20 and 40 years old) and the elderly (i.e. people over 55 years old). Results show that unaided recall is lower amongst the elderly whereas commercials with largely evaluative content result in higher miscomprehension amongst them. As compared to young adults, seniors developed more positive attitudes towards the commercials and generated more positive affective responses towards the product regardless of the commercial content, though their overall attitudes tend to be consistently neutral. Involvement towards the product plays an important mediating role, to such an extent that it blurs the effect of age group on attitude towards the product.

When a segment is expanding, it attracts the attention of many marketers. Such is the case of the elderly. It has been documented that the elderly population, as a demographic segment, is expanding twice as fast as the rest of the American population (Gorn et al., 1991). Furthermore, when one looks at current levels of education, disposable income and health, some well established myths abot the elderly (e.g. that they are marginal individuals with low disposable incomes in poor health) have to be debunked (Burnett, 1991; Stone and Fletcher, 1986). But this does not mean that this segment is without problems. For example, the over-consumption of pharmaceutical products by the elderly remains a serious issue, Lumpkin et al. (1991) point out that these customers have the greatest risk from misuse of over-the-counter (OTC) drugs. Hence, investigation of persuasive effects of advertising for OTC on the elderly becomes a real social issue. This research tackles that problem.

Several consumer behaviour studies have been conducted on the elderly. A significant body of research has focused on the persuasive effects of advertising on this group (e.g. Smith and Moschis, 1984; Burnett, 1991; Johnson and Cobb-Walgren, 1994). This paper fits into this stream of research. Specifically, we investigate the differences between the elderly and young adults in their persuasive reactions to commercials for an analgesic.

BEHAVIOR OF THE ELDERLY: SOME CONTRIBUTIONS

Several conceptual frameworks from biology, psychology and sociology have been suggested to model the behaviour of the elderly (Moschis, 1992). Despite their differences, each of these emphasizes mass media behavior as a way to counter their social disengagement. In gerontology, the literature stresses the impact of cognitive aging on the processing of advertising stimuli. An important consideration, memory deficits have an impact on the information retrieval process and the elderly experience some difficulty in linking a new piece of information to what has been stocked in memory (John and Cole, 1986; Light, 1991; Hess and Tate, 1991). This difficulty increases with age. To counter these effects of aging, Cole and Gaeth (1990) suggest the provision of individuals with instructions that facilitate the linking of new information with that in memory.

Cognitive age also affects encoding processes, comparisons and reactions to new stimuli (John and Cole, 1986; Cole and Houston, 1987; Salthouse, 1991). Specifically, information processing is affected by a lower level of selective attention resulting from aging. The elderly demonstrate a lower capacity to extract salient attributes when relevant and irrelevant stimuli are similar or when explicit information is hard to understand (Phillips and Sternthal, 1977; Cole and Gaeth, 1990; Gorn et al., 1991; Boujon, 1992; Henderson, 1995). Finally, we wish to emphasize that the elderly are more likely to be distracted when exposed to a stimuli and that such a situation has a negative impact on their information processing (Schonfeld, 1974; Gorn et al., 1991; Henderson, 1995).

These observation raise questions about the persuasive effects of advertising content, which may be either factual or evaluative. Factual content has been defined as "logical, objectively verifiable descriptions of tangible product features", while evaluative content has been defined as "emotional, subjective impressions of intangible aspects of the product" (Holbrook, 1978, p. 547). This dichotomy has been frequently used in both the advertising and the consumer behavior literature (e.g. Shimp and Preston, 1981; Perrien, Paul and Dussart, 1985; Venkatreman et al., 1990). As far as the elderly as a specific segment is concerned, understanding of the persuasive effects of these different types of advertising content is low and raises the following questions: how do they react to different advertising content, and are their reactions different from those of younger adults? Knowing that some researchers have pointed out that the elderly tend to generate fewer counter-arguments and suffer from cognitive deficits in the processing of information when exposed to persuasive stimuli, we may also question their capacity to discriminate between factual and evaluative advertising content (Salthouse, 1991; Moschis, 1992). This could e considered a social problem when the advertising in question is for pharmaceutical products. Up until now the relationships between aging and the persuasive effects of advertising have been investigated only with cognitive responses, providing for only a limited body of knowledge (Johnson and Cobb-Walgren, 1994; Henderson, 1995).

With these issues in mind, the objective of this research is to investigate the persuasive effects of different advertising content (factual vs. evaluative) on members of different age groups (the elderly vs. young adults). Persuasive effects will be generated by commercials for an analgesic. It has frequently been suggested that advertising is one of the many factors which might explain the over-consumption of drugs by the elderly (Dunnette, 1975; Petersen et al., 1979; Lumpkin et al., 1990), so this research is relevant from a social as well as a behavioral standpoint.

THE RESEARCH

The Conceptual Framework

Given the above stated research objective, the advertising content will be manipulated to be either factual or evaluative. Persuasive effects will be assessed in terms of unaided recall, comprehension-miscomprehension and attitude. The comprehension/miscomprehension of an advertising message was initially investigated by Jacoby, Hoyer and Sheluga (1980), but since then has received little attention. Yet, comprehension/miscomprehension is highly relevant to our research because it may vary significantly between the elderly and young adults due to differences in their cognitive skills. Moreover, a high level of miscomprehension may have negative social consequences, especially if it involves a pharmaceutical product. With regards to attitude, we will investigate both attitude towards the advertising message and attitude towards the product.

Several variables may moderate the persuasive effects of an advertising message. First, socio-demographic variables may alter the persuasion process. Smith and Moschis (1984) concluded that not only biological but also cognitive age (the age that I feel) and state of health may intervene as moderators. French and Crask (1977) suggest occupation as a moderator of elderly behavior and their attitudes towards advertising, having an impact greater than that of biological age. Level of education is another important variable in understanding certain elderly behaviour, such as their media habits (e.g. Dawson and Spangenberg, 1986). Finally, gender must also be taken into account, according to Sherman and Shiffman (1982), because women tend to suffer more than men from mental disorders.

It was decided to include these six variables in the design of this research. In addition, we decided to include involvement with the advertised product and media habits as well. Involvement towards the product has been documented as an important moderator of both attitude formation and persuasion (e.g. Greenwald and Leavitt, 1984; Petty and Cacioppo, 1983). For a pharmaceutical product, such as the analgesic used in this research, involvement may vary significantly between individuals. Finally, media habits cannot be overlooked in advertising research! And it has been demonstrated that this important variable is subject to some variance depending upon the age of consumers (Burnett, 1991; Schiffman, 1971).

The Design.

It was decided to use an experimental design to test the causal relationship between advertising content and its persuasive effects on the elderly and young adults. The elderly were defined as people of age 55 and above, and young adults were defined as people of ages 20 to 40. Advertisements for a fictitious brand of analgesic were designed by a professional team and were used as experimental stimuli. Analgesics are the most widely sold non-prescription pharmaeutical product (used by 92% of the overall population, according to the information we were provided by a professional association of pharmacists). The four leading advertisers who market analgesics (Bristol Myers, American Home Products, Johnson and Johnson, Sterling Drug) allocate over 80% of their media budgets to television so it was decided that the advertisements would be television commercials. A semantic analysis the brand names of analgesics marketed by the four above-mentioned companies led us to develop a brand name which would incorporate two syllabi and six letters and which would have some connotation with aspirin and acetaminophen. Consequently, we branded our analgesic "Cedrin", a name never previously used for an analgesic.

To develop the commercials’ content, a content analysis, based on the Resnick and Stern (1977) grid, was conducted on 11 commercials and revealed that the "typical" commercial focused on four points: (1) the product is new, (2) the product contains some specific ingredients, (3) the product works quickly, and (4) a visual demonstration of this. Based on these parameters, two 30 second commercials were produced. The first one was factual whereas the second one was evaluative. The factual commercial was produced first. In a second step, an advertising copy-writer was asked to develop an evaluative version of this factual commercial, with this paper’s authors ensuring that the content was fully evaluative. Three iterations were necessary to develop a final version of the evaluative commercial. Two pharmacists and one physician tested and confirmed the plausibility of the two commercials.

The two commercials were inserted into a 13 minute documentary about the city where the experiment took place. Two other commercials were also inserted which were selected at random. One advertised gum whereas the second promoted an insurance company. For validity purposes, the same interviewer conducted all the experimental sessions and the purpose of the experiment was disguised. Participants were told that the objective of the research was to better understand their media habits and their consumption patterns.

The data collection process entailed the following 5 steps:

1) Introduction and presentation of the purpose of the experiment.

2) Measurement of media habits, involvement towards the product, and socio-demographic characteristics.

3) Presentation of the experimental material (length: 15 minutes).

4) Measure of unaided recall

5) Forced exposure to the manipulated commercial.

6) Measurement of comprehension/miscomprehension, attitude towards the advertisement, and attitude towards the product.

The Experimental Units

180 consumers acted as experimental units: 90 young adults (with ages ranging from 20 to 40, mean=30) and 90 elderly people (with ages ranging from 55 to 85, mean=69). Within each of the two groups of consumers (elderly and young adults), participants were randomly assigned to one of the two commercials, resulting in 45 experimental units per cell. Elderly consumers came from a local senior citizen’s association which had no other membership restrictions (in terms of religion, past experience, education, sex, etc.). Young adults came from a local college where they were enrolled on a part-time basis. Although experimental units were randomly assigned to experimental manipulations, we also checked for any subsequent statistical differences between manipulation assignments within each of the two groups of consumers (i.e. young adults vs. the elderly). For both age and sex, the random assignment process worked ell as no statistical differences were indicated by chi-squared tests.

Measures

Unaided recall was measured with an open question, asking to identify advertised products. Comprehension/miscomprehension measures were based on Jacoby and Hoyer’s scale: a set of five "yes or no" questions related to the explicit content of manipulated commercials. For attitude we used a three dimensional model (cognitive/affective/behavioral measures) for attitude towards the product and a two dimensional model (cognitive/affective measures) for attitude towards the advertisement (Aad). A behavioral measure would have been redundant here. Attitudinal items were measured on a seven-point scale, with results also presented on such a scale. Reliability coefficients ranged from 0.76 to 0.95 for the five measures. To measure involvement we used the Personal Involvement Inventory developed by Zaichkowsky (1985). The set of 20 items resulted in a high level of reliability (0.94). To measure media habits, because the experiment involved only television advertising, we used the number of hours per day devoted to watching television. Finally, cognitive age was measured on a "feel age" scale (widely used in gerontology) where participants were asked to report "I feel like someone who is xx years old."

RESULTS

Because the ultimate objective of this research is to assess differences resulting from two stimuli on two different age groups, we relied on means comparisons.

Effects on Unaided Recall.

Manipulated content of commercials did not significantly influence unaided recall (sum of squares=0, F=0, df.= 1, 176, p=1) whereas age group resulted in a significant effect (sum of squares=5, F=33.96, df=1, p=0.0001). The magnitude of this effect was strong as it explained 17% of total variance (eta-squared measure). Interaction was not significant (sum of squares= 0.20, F=1.36, df=1, 176, p= .24). At no surprise, unaided recall was lower among the elderly (mean=0.61 vs 0.94 for young adults). Hence, cognitive deficits among senior customers started with perceptual processes.

Effects on Comprehension/Miscomprehension.

Neither the advertising content (factual vs. evaluative) nor the age group (elderly vs. young adults) resulted in significant effects on this dependent variable (content: sum of squares=2.06, F=2.46, df=1, 176, p=0.118; age group: sum of squares=0.99, F=1.18, df=1, 176, p=0.278). The interaction was significant (sum of squares=5.71, F=6.80, df=1, 176, p=0.01) although its magnitude was weak (eta-squared=4%). Looking at the means by cells provides us with an explanation. For the elderly, comprehension rate (as measured by the number of right answers) increased from 2.27 for the evaluative content to 2.84 for the factual content, whereas it did not change amongst the young adults (evaluative: 2.48; factual: 2.33). The elderly have a better comprehension of a factual message, although the magnitude of this effect tends to be weak.

Effects on Attitude Towards the Message (Aad).

A multivariate analysis of variance was conducted on the two dimensions of Aad (cognitive\affective). Advertising content did not produce any significant effect (Wilk’s Lambda=0.9845, F=1.37, df=2, 175, p=0.257), nor did the interaction, but age group did result in a significant multivariate effect (Wilk’s lambda=0.943, F=5.24, df=2, 175, p=0.006). The magnitude of this effect is 5.7% (1-0.943). To better understand this multivariate effect, a stepwise discriminant analysis was conducted, with the two groups as criteria and the wo dimensions defined as predictors (the stepwise procedure is intended to control for multicollinearity). Only the cognitive dimension accounted for the observed significant effect (F=9.12, df=1, 178, p=0.0029). Results were straightforward: regardless of advertisement content, the elderly developed a more positive cognitive reaction to the commercials than the young adults (means of the two groups: elderly=3.06, young adults=2.82). This conclusion challenges some previous research which emphasizes the negative attitude of the elderly towards advertising (Burnett, 1991; Burnett and Wilkes, 1986).

Effects on Attitude Toward the Product.

Results of the MANOVA conducted on the three dimensions of attitude towards the product were similar to those just presented for attitude towards the message. The overall multivariate effect was significant when age group was the source of variance (Wilk’s lambda=0.9357, F=3.98, df=3, 174, p=0.0089, magnitude=6.4%). Neither advertising content (Wilk’s lambda=0.9941, F=0.341, df=3, 174, p=0.79) nor the interaction (Wilk’s lambda=0.96, F=2.11, df=3, 174, p=0.10) were significant. Two dimensions of attitude towards the product explained this multivariate effect when a stepwise discriminant analysis was conducted on the two age groups with the cognitive, affective and behavioral dimensions as predictors. First, the cognitive dimension was significantly affected by age (F=4.77, df=1, 178, p=0.03). Cognition towards the product was higher for young adults (mean=3.11) than for the elderly (mean=2.94). However, on the second significant dimension which was the affective reaction to the advertised analgesic ( F=6.91, df=1, 177, p=0.0093), the elderly were more positively inclined than their younger counterparts (means: 2.93 and 2.06 respectively).

Effects of Covariates.

Recall that our set of covariates included six individual characteristics, a measure of involvement towards analgesics, as well as the number of hours spent daily watching television. The impact of this set of covariates was assessed for each of the three persuasive effects individually.

In the ANCOVA conducted on recall the manipulated content still had no effect (sum of squares=.115, F=.88, df=1, 169, p=.3505) nor did the interaction. However the effect of the age group disappeared (sum of squares=.021, F=.16, df=1, 169, p=.6876). Two covariates explained this result: "feel age" and involvement. The correlation between the former and unaided recall was substantive enough: -.4702, p=.0001, which meant that the younger the respondents felt, the higher their recall was. As far as involvement is concerned, the correlation with unaided recall was .227, p=.0022, which meant the higher the involvement was, the higher their recall of the advertised product.

The ANCOVA conducted on comprehension did not change the direct effects (age: sum of squares=.0138, df=1, 169, F=0.899, content: sum of squares=1.815, df=1, 169, p=0.14;) nor the interaction. No individual covariate had a significant effect.

With regards to attitude towards the message, involvement resulted in a significant effect (Wilk’s lambda=0.9230 F=7.00, df=2, 168, p= 0.0012). Feel age had a marginal but interesting effect (Wilk’s Lambda=.9763, F=2.039, df=2, 168, p=.13) Furthermore, these effects were powerful enough to eliminate the effect of age group (Wilk’s lambda=0.9914, F=0.72, df=2, 168, p=0.4844). Yet, the advertising content factor became significant (Wilk’s Lambda=.9598, F=.7279, df=2, 168, p=.0321). The factual message resulted in more positive attitudes on both the cognitive and affective dimensions. The interaction remained insignificant (Wilk’s lambda=0.9764, F=2.03, df=2, 168, p=0.1355). To better understand the role of covariates on attitude, once again we relied upon correlation coefficients. Involvement was once again significantly crrelated with the affective dimension of attitude towards the product (r=0.2272, p=0.0022). Feel age, although its effect was border-lined, was significantly correlated with both the cognitive dimension (r=.2264, p=.0022) and its affective counterpart (r=.2516, p=.0007). Hence, for attitudes toward a message, age did not play a major role, whereas the content directly contributed to reaction when feel age and involvement were taken into account. It emphasized the key role of psychological dimensions in attitudinal responses toward the ad.

As far as attitude toward the product was concerned, involvement played the same role. Indeed it was the sole covariate which resulted in a significant effect (Wilk’s Lambda=.892, F=6.70, df=3, 176, p=.0004). Furthermore this effect was powerful enough to eliminate the effect of age group (Wilk’s Lambda=.986, F=.771, df=3, 167, p=.511) Both the advertising content factor and the interaction remained insignificant. Involvement was once again significantly correlated with the affective dimension of attitude towards the product (r=.28257, p=.0001) and, to a lesser degree, with the behavioral dimension (r=.2025, p=.0064). The correlation between involvement and the cognitive dimension was not significant (r=.0552, p=.4618).

CONCLUSION

The main objective of this research was to investigate the impact of age on the persuasive effects of a commercial. On all of (1) unaided recall (2) comprehension/miscomprehension, (3) attitude towards the commercial, and (4) attitude towards the product, this variable had an effect. Interestingly enough, though biological age had an effect, cognitive age as measured by "feel age" did not affect the results, with the exception of recall, and to a lesser degree attitude toward the ad, which challenges the large body of research emphasizing the predictive power of cognitive age over biological age, although this conclusion is constrained by the characteristics of our sample. As stated earlier, we relied on homogenous sub-samples (young adults enrolled in evening courses and members of an senior citizen’s association) so their could have been a lower variance of the gap between cognitive age and biological age than in the overall population. This homogeneity was required by the purpose of the investigation as well as our desire to ensure internal validity. Our results suggest that biological age sheds light on differences in the persuasive effects of advertising.

When one looks at attitudinal scores, it must be acknowledged that the results coming from the elderly are closer to a neutral position than anything else, a conclusion already reached by Phillips and Sternthal (1977). Actually, these result may mean that the elderly are either reluctant to reveal their attitudes or that the latter may not result in a mere exposition to one persuasive message. The former is a measurement issue, the latter is a substantive one.

The magnitude of the experimental results was in the 4% to 6% range, which is far from being unusual in both consumer research and experimental psychology. So the elderly’s higher miscomprehension rate when exposed to an evaluative message as well as their more positive affective reaction towards an advertised pharmaceutical product does raise some ethical as well as social questions. Undoubtedly, there is a need to explore the effects of advertising on the elderly’s consumption patterns for pharmaceutical products.

The lack of an effect of advertising content on attitudinal measures means that the distinction between commercial content which is factual or evaluative does not affect attitude formation with the exception of attitude toward the ad when covariates and more precisely involvement and feel age are considered. This is a striking conclusion when one realizes that the commercials in question advertised a pharmaceutical product. It deserves additional investigation: why do the elderly not discriminate between factual ad evaluative commercials when they involve a product such as an analgesic? Involvement towards the product plays an important moderating role. It has no impact on miscomprehension, but its impact on the affective attitude towards an advertisement is significant, as well as the affective and behavioral reactions toward the product. Its impact is however powerful enough to cancel the effect of age on attitude towards the product.

Given these findings, it can be argued that socio-demographic characteristics such as age, although they have some value for explaining behavior, cannot be used without also taking into account important psychological variables such as involvement. Returning to a point made at the beginning of this paper, the behavior of a segment cannot be predicted based solely upon its socio-demographic profile. Despite the excitement generated by the size and rate of growth of the elderly segment of the population, advertisers and marketers must also consider psychological features (e.g. involvement) if they are to generate an accurate picture of their behavior.

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