1. Examining the Utility of the Theory of Planned Behavior
Psychosocial Factors Associated with Tobacco Use Intentions Among Youth:
Examining the Utility of the Theory of Planned Behavior
Brian N. Smith1, Ilene S. Speizer2, Karen S. Mitchell1, Melanie K. Bean1, Elizabeth A. Fries1
1Department of Psychology, 2Department of Preventive Medicine and Community Health, Virginia Commonwealth University, Richmond, VA, USA
Method
Tobacco-related behaviors and characteristics of students from three high schools were assessed at two time points – pre- and post-intervention. The present research involves only the baseline data.
Procedure and Participants
Participants completed a 16-page baseline survey just before the beginning of tobacco-related interventions (approximate completion time was minutes).
Upon completion of the instrument…
participants placed their survey in a blank envelope and sealed it
turned sealed envelopes over to instructor
instructors then returned sealed envelopes to the YTEP
Surveys were returned from 99% of the eligible participants (1002 out of 1117) for the present analysis
Due to missing data issues (i.e., incomplete surveys), the final sample was Demographic characteristics of participants are shown in Table 1.
Results
Smoking Intentions by Grade
Figure 1 summarizes the responses for intentions to try smoking in the next 6 months by grade.
Grade in school did not have a significant effect on behavioral intentions to try smoking
Psychosocial Predictors of Smoking Intentions
Table 2 and Figure 2 summarize the results for the logistic regression model used to predict intentions to try smoking among the non-smokers (N=730). All predictor variables were entered simultaneously.
The following covariates were included in the model, but did not yield significant effects:
Ethnicity, grade in school, whether a mother or female guardian is present in the home, and sex.
Whether a male guardian is present in the home was the only significant covariate, such that having a male guardian is associated with decreased odds of having intentions to try smoking
Results of Logistic Analysis
Attitudes: more positive attitudes toward remaining “tobacco-free” are associated with a significantly decreased odds of having intentions to try smoking
Perceived Risk (long-term consequences): not significant
Subjective Norms: marginally significant finding (p=.07)indicates that perceiving that friends’ do not want individual to smoke is associated with decreased odds of having intentions to try smoking
Smoking Among Friends: higher perceived proportion of friends who smoke is associated with a significantly increased odds of having intentions to smoke
Perceived Prevalence in community among age-group: not significant
Perceived Behavior Control to Quit Smoking: greater perceptions of control to quit are associated with significantly increased odds of having intentions to try smoking
Perceived Behavioral Control to Avoid Smoking: not significant
Discussion
Findings & Conclusions
11% of non-smoking youth indicated intentions to try smoking within 6 months
22% of all youth surveyed either currently smoke or intend to try it in the next 6 months
Smoking intentions did not vary significantly by grade
Findings regarding the roles of the TPB constructs are consistent with theory
attitudes and perceived behavioral control were significant predictors of smoking intentions, and subjective norms was marginally significant
Consistent with prior research, (Smith & Stasson, 2000), perceived behavioral control was the strongest independent predictor of intentions to engage in health-related behavior.
Limitations
Missing data, though response rates were good overall
Correlational design – causality cannot be inferred
Implications
One approach to reducing the incidence of adolescent tobacco use may be to facilitate positive attitudes with regards to remaining tobacco-free
Further research examining social influence processes may provide insight regarding how to address peer use, and the role of normative influence on tobacco use and other risky behaviors
Teaching adolescents to be appreciative of the addictive properties of nicotine may decrease inclinations to experiment with smoking.
Overview
As part of the Youth Tobacco Evaluation Project’s (YTEP) assessment of state-wide tobacco-prevention programming in Virginia, participants from three high schools in rural Virginia were surveyed using a comprehensive instrument to assess smoking-related characteristics and behaviors at baseline.
Guided by the Theory of Planned Behavior (TPB; Ajzen, 1985, 1991), the focus of the present research was to examine the roles of attitudes, subjective norms (and other normative factors), and perceived behavioral control in explaining adolescents’ behavioral intentions to try smoking.
Background
Tobacco use is cited as the most preventable cause of death in the United States.
Most adult smokers began smoking during adolescence, making tobacco prevention among youth an especially important mission in health research.
In the U.S., 28.5% of high school students currently smoke cigarettes; and, 13.8% are frequent current smokers, defined as having smoked on at least 20 of the 30 days preceding the survey (MMWR, 2002)
Given the robust addictive properties of nicotine, it is important to identify factors that may be related to, and predictive of, adolescents’ intentions to try smoking.
According to the TPB, an individual’s behavioral intention represents the most immediate influence on behavior; further, intentions are dependent on three sets of variables: attitudes toward the behavior, subjective norms regarding the behavior, and perceived behavioral control.
Table 2. Odds Ratios and Confidence Intervals for
Predictors of Behavioral Intentions to Try Smoking
Psychosocial Predictor
Intentions to Try Smoking
Odds Ratio % C.I.
Attitudes (Tobacco-Free)*
Perceived Risks (Long-Term)
Subjective Norms
Smoking Among Friends*
Perceived Prevalence
PBC to Quit Smoking**
PBC to Avoid Smoking
Father or Male Guardian*
Present
*p<.05, **p<.001
Table 1. Participant Characteristics
Characteristics of Sample
Percentage in Group
Total N = 940
Grade In School
9th
10th
11th
12th
23.3
21.4
29.5
25.9
Sex
Girl
Boy
53.2
46.8
Ethnicity
African American
Caucasian
Hispanic/other
12.9
71.6
5.1
Intend to Try Smoking Within the Next 6 Months No
Yes
Already Smokes
68.9
8.7
13.3
Intend to Try Smoking Within the Next 30 Days
71.0
6.7
Current Research
Key Variables (from the TPB):
Attitudes toward remaining tobacco free
7-item index on 5-pt continuum
Subjective Norms regarding tobacco use
single item index on 5-pt continuum
Perceived behavioral control to quit smoking
among non-smokers; single item index on 5-pt continuum
Perceived behavioral control to avoid smoking
once deciding not to smoke; single item index on 5-pt continuum
Intentions to try smoking in the next 6 months
among non- smokers; single item index on 5-pt continuum
The following variables were also assessed to expand on the TPB constructs:
Attitudes / Perceived Risks regarding long-term consequences of smoking
4-item index on 5-pt continuum
Proportion of friends that smoke
Single-item index on 5-pt continuum: “none-few-half-most-all”
Perceived prevalence of smoking among age group
References
Ajzen, I. (1985). From intentions to actions: A Theory of Planned Behavior. In J. Kuhl & J. Beckman (Eds.) Action-control: From cognition to behavior (pp ). Heidelber, Germany: Springer.
Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50,
Fishbein, M., & Ajzen, I. (1975). Belief, attitude, intention, and behavior: An introduction to theory and research. Reading, MA: Addison-Wesley.
MMWR – Trends in Cigarette Smoking Among High School Students – United States, , 51 (19). May 17, 2002.
Smith, B.N., & Stasson, M.F. (2000). A comparison of health-behavior constructs: Social Psychological Predictors of Aids-Preventive Behavioral Intentions. Journal of Applied Social Psychology, 30,
Acknowledgements: Funding for this project was provided by the Virginia Tobacco Settlement Foundation (VTSF)