Having Casual Sex: Additive and Interactive Effects of Alcohol and Condom Availability on the Determinants of Intentions

The impact of alcohol, condom availability, and gender on intentions to engage in casual sex and its antecedents was investigated. Students ( N = 384) who were or were not intoxicated with alcohol completed measures based on the theory of planned behavior (TPB) in relation to having casual sex in a scenario. The scenario described sex between 2 individuals not in a relationship and manipulated the consumption of alcohol of the sexual partners and availability of condoms. The data were supportive of the TPB: Intentions were predictable from attitudes, subjective norms, and perceived behavioral control (PBC). Results also support the inclusion of measures of past behavior and anticipated affective reactions, but not self-identity or moral norms as predictors of intentions. Alcohol in the scenario and condom availability increased intentions to have sex. There were also several interaction effects. Implications for using the TPB to understand sexual behaviors under the influence of alcohol are discussed.     

Antecedents of children's physical activity intentions and behaviour: Predictive validity and longitudinal effects

Abstract

This study examined the predictive validity and time-lagged relationships in a model of children's physical activity intentions, attitudes, perceived behavioural control (PBC), behaviour and past behaviour using the Theory of Planned Behaviour (TPB; Ajzen, 1985) as a framework. In Study 1, 386 children aged 12–14 years completed measures of intentions, attitudes, subjective norm, PBC and past behaviour. Their physical activity behaviour was assessed one week later. Structural equation analyses supported the construct and predictive validity of the TPB with the exception of subjective norms which did not predict intentions. In Study 2,70 children completed measures of their physical activity attitudes, intentions, PBC and past behaviour. Attitudes, intentions, PBC and recent behaviour were re-assessed five weeks later. The cognitions demonstrated a moderate degree of stability over time and there were some cross-lagged effects between attitudes and PBC. Past behaviour demonstrated additive rather than attenuating effects. These results support the use of the TPB cognitions and past behaviour as a framework to examine children's physical activity behaviour.     

Interaction Effects in the Theory of Planned Behavior: The Interplay of Self-Identity and Past Behavior

This research used a revised theory of planned behavior (TPB) model, which incorporated self-identity and past behavior—and the interaction between these constructs—in order to improve the model's predictive power in relation to consumer behavior (purchasing one's preferred beer). At Time 1, respondents ( N  = 108) completed measures of attitudes, perceived behavioral control, subjective norm, self-identity, past behavior, and intentions. Behavior was assessed 1 week later. All predictors were positively related to intentions. Self-identity and past behavior interacted to influence intentions: Self-identity had a stronger influence on intentions at low, rather than high, levels of past behavior. Intentions and past behavior were predictive of Time 2 behavior. These findings emphasize the need to consider identity issues in the TPB.     

To Be a Donor or Not to Be? Applying an Extended Theory of Planned Behavior to Predict Posthumous Organ Donation Intentions

Using a theory of planned behavior (TPB) perspective, individual intentions to register and discuss the decision of organ donation with significant others were examined. In addition to standard TPB variables (attitude, subjective norm, and perceived behavioral control [PBC]), self-identity and moral norm were incorporated into the TPB as predictors. Australian university students ( N  = 303) completed a survey comprising standard and additional TPB constructs. Separate analyses were conducted for both registered and nonregistered participants. In general, results provide support for the extended TPB model in predicting intentions to register and discuss the donation decision, with the exceptions that self-identity did not predict discussion intentions for either registered or nonregistered participants, and PBC did not predict discussion intentions for nonregistered participants.     

Extending the Theory of Planned Behavior: A Review and Avenues for Further Research

This paper describes and reviews the theory of planned behavior (TPB). The focus is on evidence supporting the further extension of the TPB in various ways. Empirical and theoretical evidence to support the addition of 6 variables to the TPB is reviewed: belief salience measures, past behavior/habit, perceived behavioral control (PBC) vs. self-efficacy, moral norms, self-identity, and affective beliefs. In each case there appears to be growing empirical evidence to support their addition to the TPB and some understanding of the processes by which they may be related to other TPB variables, intentions, and behavior. Two avenues for expansion of the TPB are presented. First, the possibility of incorporating the TPB into a dual-process model of attitude–behavior relationships is reviewed. Second, the expansion of the TPB to include consideration of the volitional processes determining how goal intentions may lead to goal achievement is discussed.     

The role of self-efficacy in predicting rule-following behaviors in shelters for homeless youth: a test of the theory of planned behavior

Through a prospective study of 70 youths staying at homeless-youth shelters, the authors tested the utility of I. Ajzen's (1991) theory of planned behavior (TPB), by comparing the constructs of self-efficacy with perceived behavioral control (PBC), in predicting people's rule-following behavior during shelter stays. They performed the 1st wave of data collection through a questionnaire assessing the standard TPB components of attitudes, subjective norms, PBC, and behavioral intentions in relation to following the set rules at youth shelters. Further, they distinguished between items assessing PBC (or perceived control) and those reflecting self-efficacy (or perceived difficulty). At the completion of each youth's stay at the shelter, shelter staff rated the rule adherence for that participant. Regression analyses revealed some support for the TPB in that subjective norm was a significant predictor of intentions. However, self-efficacy emerged as the strongest predictor of intentions and was the only significant predictor of rule-following behavior. Thus, the results of the present study indicate the possibility that self-efficacy is integral to predicting rule adherence within this context and reaffirm the importance of incorporating notions of people's perceived ease or difficulty in performing actions in models of attitude-behavior prediction.     

To share or not to share: A theoretically guided investigation of factors predicting intentions to use fully automated shared passenger shuttles

This study applied the Theory of Planned Behaviour (TPB) to assess individuals’ intentions to use fully automated shared passenger shuttles when they become publicly available. In addition, perceived trust was assessed to examine the extent to which this variable could account for additional variance in intentions above the TPB constructs of attitudes, subjective norms, and perceived behavioural control (PBC). Further, and also guided by the TPB, the study explored the differences in behavioural, normative, and control beliefs between individuals who reported high intentions to use automated passenger shuttles in the future (high intenders) and individuals who reported low intentions to use fully automated shared passenger shuttles in the future (low intenders). Participants (N = 438; 64% female) aged between 17 and 84 years (Mage = 35.42 years) were asked to complete an online questionnaire which took approximately 15 min. The findings revealed that attitudes, subjective norms, and PBC were significant positive predictors of intentions to use fully automated shared passenger shuttles when they become publicly available. When perceived trust was added to the hierarchical regression, this variable was shown to account for additional significant variance in intentions above the TPB constructs and was shown to be a significant positive predictor of intentions. Further, the results revealed significant differences in beliefs held by high and low intenders. Specifically, high intenders held significantly more positive beliefs towards fully automated shared passenger shuttles than low intenders. In turn, low intenders held significantly more negative beliefs towards these vehicles than high intenders. Overall, these findings provide support for the utility of the TPB in examining individuals’ intentions to use fully automated shared passenger shuttles when they become publicly available.     

Application of the theory of planned behaviour to the prediction of objectively assessed breaking of posted speed limits

In two studies the Theory of Planned Behaviour (TPB) including moral norms, anticipated regret and past behaviour was applied to predicting intention to exceed the posted speed limit across different roads and objectively assessed speeding behaviour. All measures except behaviour were taken by self‐report questionnaires referring to different driving scenarios. The behaviour measures were based on performance in a simulator (Study 1) or unobtrusive on‐road speed camera assessment taken without driver awareness (Study 2) across roads with varying posted speed limits. Results are reported averaged across road types in both studies. In Study 1 (N = 83), 82% of the variance in intentions to speed was explained, with attitudes, subjective norms, perceived behavioural control (PBC), moral norms, anticipated regret and past behaviour being significant predictors. A total of 35% of the variance in speed as assessed on a driving simulator was accounted for with intentions, PBC, moral norms and previous accidents being significant predictors. In Study 2 (N = 303), 76% of the variance in intentions to speed was explained with attitudes, moral norms, anticipated regret and past behaviour being significant predictors. A total of 17% of the variance in speed as assessed on‐road was accounted for with intentions and moral norms being significant. Practical implications of the findings for road safety are discussed.     

Predictors of Young People's Charitable Intentions to Donate Money: An Extended Theory of Planned Behavior Perspective

An extended theory of planned behavior (TPB) was used to predict young people's intentions to donate money to charities in the future. Students (N = 210; 18–24 years) completed a questionnaire assessing their attitude, subjective norm, perceived behavioral control (PBC), moral obligation, past behavior, and intentions toward donating money. Regression analyses revealed that the extended TPB explained 61% of the variance in intentions to donate money. Attitude, PBC, moral norm, and past behavior predicted intentions, representing future targets for charitable‐giving interventions.     

Organ donation intentions and behaviors: application and extension of the theory of planned behavior

Organ donation intentions and behaviors were investigated using a traditional and extended theory of planned behavior (TPB). In study 1, attitudes, subjective norms, and perceived behavioral control were associated with intentions to engage in donation behaviors in a student sample (all p ≤ .02), and intentions significantly predicted behavior 2 months later (p < .001). Study 2 utilized a community sample of Catholic, Jewish, and Muslim individuals. Measures of affect and religious attitudes were added to the traditional TPB, increasing the variance in intentions accounted for by the model, F(7, 181) = 6.94, p < .001. The studies support the use of an extended TPB in predicting donation‐related intentions and behaviors and suggest potential targets of interventions to promote donation.     

Staying grounded? Applying the theory of planned behaviour to explore motivations to reduce air travel

Air travel has been highlighted as a key environmental behaviour contributing to climate change. Given this, there is a surprising lack of theory-based research aimed at identifying factors that underpin motivation to reduce the number of flights taken. This study explored whether an extended theory of planned behaviour (TPB) model could be usefully applied to identify significant predictors of intentions to reduce the number of flights taken for leisure, holidays or to visit family or friends. Results supported the predictive utility of the TPB; the extended model was able to account for 52% of the variance in intentions over and above past behaviour and socio-demographic variables. Attitudes, subjective norms and behaviour-specific self-identity emerged as significant linear predictors. Findings support the utility of applying the TPB to air travel and suggest key variables which could be targeted in interventions to promote motivation to reduce the number of flights taken.     

Group processes in food choices: The role of ethnic identity and perceived ethnic norms upon intentions to purchase ethnical food products

A study tested an extended Theory of Planned Behaviour (TPB) model, inclusive of measures of ethnical identification and perceived ethnic group norms, in the ethnical food purchasing domain. One hundred and thirty‐five Jamaicans, living in the Brixton neighbourhood, London, were administered a self‐reported questionnaire measuring the classical TPB components (attitudes, subjective norms, perceived behavioural control, behavioural intentions) plus three additional components: identification with the Jamaican group, perceived norms of the Jamaican group and past behaviour. Results of hierarchical multiple regressions showed that past behaviour, ethnical identification and perceived group norms explain an additional proportion of variance in intentions, independently of attitudes, subjective norms and perceived control. A two‐way interaction, between ethnical identification and perceived group norms, was detected. A stronger relation between group norms and intentions emerged among high ethnical identifiers. Theoretical and practical implications are discussed. Copyright © 2008 John Wiley & Sons, Ltd.     

Distinguishing Between Perceived Behavioral Control and Self-Efficacy in the Domain of Academic Achievement Intentions and Behaviors

We examined whether perceived behavioral control (PBC) and self-efficacy (S-E) can be distinguished empirically, and whether they make different contributions to the prediction of intentions and behavior. The behavioral criterion was performance in 3 high-school examinations. Measures of attitude, subjective norm, PBC, S-E, and intention were taken before the examinations. Grade achieved served as the behavioral measure. Factor analysis of items intended to measure PBC and S-E extracted 2 factors: confidence in ability to achieve the behavioral outcome, and belief that the outcome can be influenced by own efforts. Scores on these factors were labeled S-E and perceived control, respectively. Behavior was predicted better by S-E than by intentions, and intentions were more closely related to S-E than to attitudes, subjective norms, or perceived control.     

Assessing the feasibility of the theory of planned behaviour in predicting drivers’ intentions to operate conditional and full automated vehicles

Guided by the Theory of Planned Behaviour (TPB), this study examined the beliefs underpinning, and feasibility of the factors in predicting, individuals’ intentions to use a conditional (Level 3) automated vehicle (AV) and a full (Level 5) AV. Australian drivers (N = 505) aged 17–81 years (Mean age = 33.69, SD = 18.79) were recruited and completed a 20 min online survey which featured both quantitative and qualitative items. For the quantitative data, two linear regressions revealed that the TPB standard constructs of attitudes, subjective norm, and perceived behavioural control (PBC) accounted for 66% of the variance in intentions to use a conditional AV and 68% of the variance in intentions to use a full AV. Of the TPB constructs, attitudes and subjective norms were significant positive predictors of future intentions to use conditional and full AVs. For the qualitative data, some differences emerged for the underlying behavioural beliefs that underpinned intentions to use conditional and full AVs. For example, having beliefs about control over the conditional AV was identified by many participants as an advantage, while not being in full control of the full AV was identified as a disadvantage. For underlying control beliefs, participants identified similar barriers for both vehicle types, including; high costs, lack of trust, lack of control over the vehicle, lack of current legislation to support the mainstream introduction of these vehicles, and concerns of safety for self and for other road users when operating AVs. Overall, these findings provide some support for applying the TPB to understand drivers’ intended use of AVs. However, while the current study showed that the constructs of attitudes and subjective norms might reflect intended use of AVs, more research is required to further examine the role of PBC. Additionally, the findings provide initial insights into the underlying behavioural and control beliefs that may motivate drivers to use AVs and highlight the similarities and differences in drivers’ perceptions towards two levels of vehicle automation.     

A test of theory of planned behavior in Korea: participation in alcohol-related social gatherings

Two studies are reported using the theory of planned behavior (TPB) to predict and explain joining and not joining alcohol-related social gatherings among Korean undergraduates in various engineering majors. Specifically, considering that the attitudinal component of TPB is behavioral-outcome-based, the current study investigated whether the outcomes of engaging in a behavior and of not engaging in a behavior would similarly predict intentions to engage in a behavior and intentions to not engage in a behavior. The current study also examined whether intentions to engage and intentions to not engage would be significantly related to self-reported behavior a week later. Participants in Study 1 reported TPB components (attitudes toward behavior, subjective norms, perceived behavioral control, and behavioral intentions) concerning joining alcohol-related social gatherings. Participants in Study 2 reported TPB components concerning not joining alcohol-related social gatherings. Additionally, a week later, the participants in both studies reported their participation in alcohol-related social gatherings from the past week. Generally, the results showed that the TPB components were significantly associated with undergraduates' intentions to join and intentions to not join. Specifically, conversation-related attitudes and senior-junior relationship-related attitudes were significantly related to intentions to join, and only group-related attitudes were significantly related to intentions to not join. Intentions to join and intentions to not join were not significantly related to self-reported behavior of joining alcohol-related social gatherings a week later. The findings from the current research provide some evidence that joining or not joining alcohol-related social gatherings may not be mere behavioral opposites, predictable by the presence or absence of the same behavioral outcomes. These two aspects of the behavior may require assessment of different behavioral outcomes or different assessments of the same behavioral outcomes.     

Predicting the Use of Complementary Medicine: A Test of the Theories of Reasoned Action and Planned Behavior1

The present study employed the theory of reasoned action (TRA) and its extension, the theory of planned behavior (TPB), to investigate the factors underlying intentions and actual use of homeopathy over a 1‐month period. The study was prospective in design; 349 respondents completed a TPB questionnaire during the first phase of data collection, and 139 respondents were contacted (by telephone) in Phase 2 to provide information regarding their use of homeopathy. The findings provided support for the TPB as a predictor of intentions and use of homeopathy, and demonstrated that the model significantly enhanced the predictive utility of the TRA. Attitudes, subjective norms, and perceived control emerged as significant predictors of intention (R²= .49), while intention predicted behavior (R²= .56). In addition, past behavior significantly contributed to the prediction of intention and behavior.     

Studying, Practicing, and Mastering: A Test of the Model of Goal-Directed Behavior (MGB) in the Software Learning Domain

The present study tested the model of goal-directed behavior (MGB). The model proposes that behavioral intentions to perform instrumental behaviors are primarily motivated by desires to perform the acts. In turn, desires mediate the effects of attitudes, subjective norms, perceived control, and anticipated emotions on intentions. Construct validity for MGB variables is assessed, and the predictive utility of the MGB is compared with that of the theory of planned behavior (TPB). College students ( N = 102) provided measures for MGB and TPB variables while participating in a training program to use statistical software. We focused on two goal-related instrumental behaviors: studying handbooks and practicing with the package. The results show that the MGB accounts for a greater proportion of variance in intentions and instrumental behaviors than does TPB. Although desires mediate most of the effects of other predictors on intentions to perform the instrumental behaviors, it is proposed that when the behavior is normatively relevant, or when self-efficacy appraisals play a major role, subjective norms and perceived behavioral control may directly affect intentions.