The theory of planned behaviour and binge drinking: Assessing the moderating role of past behaviour within the theory of planned behaviour

A sample of 398 undergraduate students completed questionnaires assessing the main constructs of the theory of planned behaviour (TPB) in relation to binge drinking, as well as past binge drinking behaviour. Of these, 273 were followed up at 1 week. Regression analyses revealed attitude, self‐efficacy, and perceived control (negative relationship) to be predictive of binge drinking intentions. Intention and self‐efficacy were, in turn, predictive of binge drinking at 1‐week follow‐up. Past behaviour was found to explain additional variance in intention and behaviour. In addition, past behaviour was found to moderate the attitude–intention and intention–behaviour relationships, such that weaker relationships were observed with increasing frequency of past behaviour. The results are discussed in relation to the need to develop and test alternative measures of habit. The implications of the findings for interventions to encourage more appropriate drinking behaviour are outlined.     

Promoting exercise behaviour: An integration of persuasion theories and the theory of planned behaviour

Objectives: The purpose of this study was to examine the effectiveness of a theoretical integrated persuasive message on exercise motivation in college students. Method: Four hundred and fifty introductory psychology students (M age = 20.02 years;SD = 3.94) were randomly assigned to reading positively or negatively framed strong messages advocating exercise. The messages were attributed to a credible source, a non‐credible source or to a no‐source control condition. Theory of planned behaviour (TPB) constructs (i.e. attitude, subjective norm, perceived behavioural control) and cognitive responses (i.e. thought listing) were measured immediately and 2 weeks following the delivery of the intervention. Results: Unfortunately, the results did not corroborate previous research, as we did not find any significant effects between experimental groups on any psychological or behavioural variable. Conclusions: There may be several potential explanations for the lack of effects, including the interaction between the type of persuasive information (TPB implications) and sources of persuasion and how these persuasive messages are processed (elaboration likelihood model/cognitive response implications). The theoretical implications of this research are discussed with a view towards future directions for exercise promotion initiatives using theoretically driven interventions.     

The role of perceived need within the theory of planned behaviour: A comparison of exercise and healthy eating

Objectives: This study examined the effect of perceived need on exercise and healthy eating using the theory of planned behaviour (TPB). In addition, it investigated the determinants of perceived need. Method: Participants completed a questionnaire measuring components of TPB and perceived need. A follow‐up questionnaire 1 week later measured behaviour. The questionnaires were completed by e‐mail. The initial questionnaire was completed by 331 adults, and 286 follow‐up questionnaires were returned. Results: Perceived behavioural control was the main predictor of exercise intention and affective attitude was the main predictor of healthy eating intention. Perceived need significantly contributed to the prediction of healthy eating intention but not to exercise intention. Intention and perceived behavioural control predicted actual behaviour but perceived need did not. Reasons reported for the perception of needing to engage in both behaviours mainly focused on physical health and weight control. Conclusions: Reasons reported for low perceived need suggest that the concept of perceived need may be rather ambiguous, particularly in the case of exercise. Therefore, further research is needed to elucidate the role of perceived need in relation to a variety of health behaviours.     

Integrating the theory of planned behaviour and self‐determination theory in health behaviour: A meta‐analysis

Purpose A meta‐analysis of studies integrating the theory of planned behaviour (TPB) and self‐determination theory (SDT) in health contexts is presented. The analysis aimed to provide cumulative empirical support for a motivational sequence in which self‐determined motivation from SDT predicts the proximal predictors of intentions and behaviour from the TPB. Methods A literature search identified 36 integrated studies providing 45 tests of effects between TPB and SDT variables. Hunter and Schmidt's (1994) methods of meta‐analysis were used to correct the effect sizes across the studies for statistical artifacts. Age (old versus young), publication status (published versus unpublished), study design (correlational versus experimental/intervention), and behaviour type (physical activity versus other health‐related behaviours) were evaluated as moderators of the effects. A path‐analysis using the meta‐analytically derived correlations was conducted to examine the proposed motivational sequence. Results Statistically significant corrected correlations were evident among the perceived autonomy support and self‐determined motivation constructs from SDT and the attitude, subjective norms, perceived behavioural control, intention, and health‐related behaviour constructs from the TPB. Only six of the 28 effect sizes were moderated by the proposed moderators. Path analysis revealed that the significant effects of self‐determined motivation on intentions and behaviour were partially mediated by the proximal predictors from the TPB. Conclusions Evidence from this synthesis supported the theoretical integration and proposed motivational sequence. Results are discussed with reference to the complementary aspects of the TPB and SDT and the need for integrated experimental or intervention studies on a broader range of health behaviours.     

Autonomy and control: augmenting the validity of the theory of planned behaviour in predicting exercise

This study examined the utility of the theory of planned behaviour (TPB) along with additional constructs in predicting exercise, and explored the motivational antecedents of exercise intentions. Participants included 162 Canadian University College students (61% females). Measures of TPB, autonomous and controlling intention, perceived autonomy support and core autonomous intention were completed during phase 1 of data collection. Two and three weeks later behaviour was assessed. Hierarchical regression analyses revealed that: (a) attitude and perceived behavioural control significantly predicted TPB intention and core autonomous intention; (b) subjective norm predicted controlling intention; and (c) perceived autonomy support predicted autonomous and core autonomous intention. TPB intention significantly predicted behaviour. TPB is a fairly useful model for predicting behaviour and important information can be gained when other measures of intention are explored.     

Predicting breakfast consumption: An application of the theory of planned behaviour and the investigation of past behaviour and executive function

Objectives . The objective of the current study is to examine the determinants of breakfast consumption with the application of the Theory of Planned Behaviour (TPB; 1991) and investigate the additional variables of past behaviour and executive function. Design . A prospective 1‐week study investigating the predictive ability of TPB variables, past behaviour and executive function was utilized. Methods . Ninety‐six participants were administered two measures of executive function (response inhibition and planning) and completed self‐report questionnaires regarding their attitudes, subjective norms, perceived control, intentions and past behaviour of breakfast consumption. One week later, participants returned a follow‐up questionnaire on their behaviour. Results . The result of the study showed that the TPB significantly predicted intentions and prospective behaviour of breakfast consumption, however, past behaviour was found to be the strongest predictor of future behaviour. Considering executive function, response inhibition was not found to predict behaviour, however, planning ability explained unique variance in behaviour and moderated the association between intention and behaviour. Conclusions . The findings support the use of the TPB in explaining breakfast eating habits, and suggest that executive function of planning may be somewhat useful to predict this behaviour. The significance of past behaviour also suggests that breakfast consumption may commonly be a stable, habitual behaviour that may undermine the need for self‐regulation. Implications for creating behavioural‐change interventions are discussed.     

Young adults' social drinking as explained by an augmented theory of planned behaviour: The roles of prototypes,willingness, and gender

Objective. This study focused on young adults' alcohol consumption in social contexts. A dual‐process model (including reasoned action and social reaction) was applied by combining the theory of planned behaviour (TPB) and the prototype/willingness model. A key question was whether willingness and actor and abstainer prototype variables would augment the TPB by increasing explained variance. Design. Participants completed questionnaires prior to spending an evening socializing over the weekend (Time 1). Behavioural data were obtained by telephone interviews a few days after the social drinking occasion (Time 2). Method. N =300 people (mean age 25 years) took part in the study. The outcome measure of pure alcohol in grams was calculated based on participants' reports about their consumed drinks. Multigroup path analyses were conducted because of sex differences on behavioural and psychological variables. Results. The TPB explained 35% of the variance in men's and 41% in women's alcohol consumption. Augmentation with prototype perception and willingness contributed significantly to the prediction of intention (ΔR²=.07) and alcohol consumption for men (ΔR²=.14). A significant interaction implied that willingness led to heavy drinking particularly among those men who made negative evaluations of the abstainer prototype. Conclusion. Women's alcohol consumption is explained by TPB variables via a more controlled reasoned‐action path only, whereas additional processes (e.g., pursuing the actor image intentionally, rejecting the abstainer image more intuitively) are important for men. The moderating role of gender is discussed in light of traditional gender roles and recent trends in alcohol consumption.     

Use of mental simulations to change theory of planned behaviour variables

Objectives The predictive validity of the theory of planned behaviour is well established, but much less is known about: (a) whether there are causal relationships between key components of the model and (b) how to go about changing the theory of planned behaviour variables. This study tested the ability of outcome and process simulations to change variables specified in the theory of planned behaviour in relation to blood donation. Design Participants (N = 146) were randomized to one of four conditions: outcome simulation only, process simulation only, process‐plus‐outcome simulation and a distractor control condition. The dependent variables were state anxiety, and intention attitude, subjective norm and perceived control from the theory of planned behaviour. Methods Participants were asked to empty their mind and visualize themselves: (a) after donating blood (outcome manipulation), (b) preparing to donate blood (process manipulation), (c) both preparing to donate blood and after having donated blood (process‐plus‐outcome manipulation) or (d) both preparing to get a high mark and after having got a high mark on their course (control condition). Following mental rehearsal, participants completed the dependent variables. Results There were no main effects of outcome simulation, but process simulation successfully increased intention, subjective norm and perceived control. There was also a significant outcome simulation × process simulation interaction for attitude. The effect of the process manipulation on intention was mediated by subjective norm and perceived control. Conclusions The findings show promise for the use of mental simulations in changing cognitions and further research is required to extend the present findings to other health behaviours.     

A meta-analysis of the effects of measuring theory of planned behaviour constructs on behaviour within prospective studies

Measurement reactivity effects, such as the mere measurement effect, have been proposed as a reason for behavioural changes in a number of theory of planned behaviour intervention studies. However, it is unclear whether such changes are the result of the mere measurement effect or of other artefacts of intervention study design. The aim of this study is to determine the size and direction of changes in health behaviours from baseline to follow-up in prospective studies using the theory of planned behaviour. Electronic databases were searched for the theory of planned behaviour studies which measured health behaviours at two or more time points. Change in behaviour was calculated for all studies. Sixty-six studies were included. Mean effect sizes across all studies were small and negative (d = ?.03). Effect size was moderated by behaviour, behaviour type and follow-up length. Subgroup analyses showed significant decreases in socially undesirable behaviour (d = ?.28), binge drinking (d = ?.17), risk driving (d = ?.20), sugar snack consumption (d = ?.43) and sun-protective behaviour (d = ?.18). Measurement of intention at baseline resulted in significant decreases in undesirable behaviour. Changes in undesirable behaviours reported in other studies may be the result of the mere measurement effect.     

Applying an extended model of the theory of planned behaviour to breast self-examination

Few studies have examined the predictors of breast self-examination in younger women, where it is the primary method for the early detection of breast cancer. Female college students (N = 253, aged 17 to 50 years) completed items related to breast self-examination assessing theory of planned behaviour (TPB) constructs (intentions, attitude, subjective norm, perceived behavioural control), social influence variables of self-identity and group norm, and demographic characteristics. One month later, breast self-examination behaviour was assessed. Results supported this application of the TPB model and highlight the importance of group norms for strategies to increase breast self-examination in younger women.     

The theory of planned behaviour as predictor of exercise: the moderating influence of beliefs and personality variables

In a test of the predictive utility of the theory of planned behaviour alone and in conjunction with a number of additional variables, 114 participants completed questionnaires measuring predictor variables and, three weeks later, reported exercise. The results of the present study provide partial support for the theory. Past behaviour was the most predictive variable. Subjective norm was not a significant predictor of intention to exercise. Attitude towards exercise was also not a predictor of exercise intention. Self-monitoring acted as a moderator of the attitude-intention relationship. Perceived behavioural control was not a significant predictor of exercise behaviour, while exercise intentions were only weak predictors. The results also suggested that perceived behavioural control and perceived barriers are not equivalent, and should be treated as separate variables that contribute independently to the predictive ability of the model. The implications of the findings are discussed.     

Using past behaviour and spontaneous implementation intentions to enhance the utility of the theory of planned behaviour in predicting exercise

Objectives. This study examined the utility of the theory of planned behaviour (TPB), past behaviour, and spontaneous implementation intentions in predicting exercise behaviour. The psychological correlates of spontaneous implementation intentions and the moderating effects of intention, perceived behavioural control, past behaviour, and implementation intentions at various time points were also examined. Design. Data collection occurred over three phases with a 2‐ and 3‐week interval. The attrition rate was 35.97% leaving a total of 162 participants (63 males, 99 females). In the first wave, participants completed measures of TPB, spontaneous implementation intentions, and past behaviour. Behaviour was assessed in the second and third waves, and a follow‐up measure of spontaneous implementation intentions was completed in Phase 3. Results. Several regression analyses were conducted. Attitude towards exercise and perceived behavioural control made a significant contribution to the prediction of intention. Intention made a significant contribution to the prediction of implementation intentions. Spontaneous implementation intentions reduced the effect of intention and past behaviour for behaviour at 2 weeks and when indexed over a 5‐week period. When behaviour was measured for a 3‐week period (following an initial 2‐week period), the variance that intention and past behaviour accounted for in exercise behaviour decreased, and spontaneous implementation intentions were no longer a significant predictor of behaviour. Spontaneous implementation intentions were found to interact with past behaviour, such that implementation intentions predicted exercise behaviour only among participants who did not exercise frequently in the past. Conclusions. Implications and future research directions are discussed.     

Cognitive mediators of the social influence-exercise adherence relationship: A test of the theory of planned behavior

The purpose of this study was to examine cognitive constructs from the theory of planned behavior (i.e., attitude, perceived behavioral control, and intention) as potential mediators of the relationship between selected social influence constructs (i.e., subjective norm, social support, and cohesion) and adherence to structured exercise classes. Sixty-two participants completed self-administered questionnaires during the fourth week (social influence constructs) and eighth week (cognitive constructs) of a 12-week exercise program. Exercise adherence was monitored during weeks 9 through 12 using perceived intensity and attendance. Pearson correlations indicated that social support correlated with perceived behavioral control, whereas cohesion correlated with attitude. Path analysis supported two distinct paths from social influence to exercise adherence: (a) social support perceived behavioral control intention excersise adherence, and (b) cohesion attitude intention exercise adherence. Discussion focuses on the theoretical importance of these findings, conceptual and measurement issues regarding subjective norm, and suggestions for future research.