Adherence to Hormone Replacement Therapy: A Longitudinal Study Using the Theory of Planned Behaviour

The aim of this longitudinal study was to assess the stability and determinants of the intention to adopt HRT over a one-year period using the Theory of Planned Behaviour. At baseline, a total of 644 middle-aged premenopausal women who had never used HRT, were recruited. At follow-up, 417 women completed an interview to assess any change in their reproductive status and in their behavioural intention. Among women who stayed premenopausal (n = 172) and among those who became perimenopausal (n = 209), the intention to adopt HRT was quite stable over the one-year period. However, being perimenopausal had a significant effect on the intention to adopt HRT at follow-up, as did subjective norm, perceived behavioural control and moral norm measured at baseline. Attitude towards HRT did not have a significant effect on the intention to adopt HRT one year later. Therefore, interventions to support women's decision-making about HRT should be tailored to their menopausal status and take into account their perception of social pressure to perform, control over this behaviour and moral obligation.     

Application of the Theory of Planned Behaviour in Behaviour Change Interventions: A Systematic Review

This paper reviews studies explicitly applying the Theory of Planned Behaviour (TPB) to behaviour change interventions. A systematic and multiple search strategy identified 30 papers, describing 24 distinct interventions. Studies were rarely explicit about use of the TPB. The TPB was mainly used to measure process and outcome variables and to predict intention and behaviour, and less commonly to develop the intervention. Behaviour change methods were mostly persuasion and information, with increasing skills, goal setting, and rehearsal of skills used less often. When reported, half of the interventions were effective in changing intention, and two-thirds in changing behaviour, with generally small effect sizes, where calculable. Effectiveness was unrelated to use of the theory to develop interventions. Evidence about mediation of effects by TPB components was sparse. The TPB may have potential for developing behaviour change interventions, but more comprehensive studies are needed that compare the utility of the TPB with other social cognition models and behavioural techniques.     

Accounting for the Theory of Planned Behaviour in departure time choice

Motivating people to change their departure time could play a key role in reducing peak-hour congestion, which remains one of the most prevalent transport problems in large urban areas. To achieve this behavioural change, it is necessary to better understand the factors that influence departure time choice. So far departure time choice modelling focussed mainly on objective factors, such as time and costs as main behavioural determinants. In this study, we derived psychological factors based on the Theory of Planned Behaviour, estimated them based on structural equation modelling, and included them into a discrete choice model. The psychological factors were measured based on an online questionnaire addressed to car commuters to the city centre of Copenhagen (N = 286). The questionnaire additionally included a travel diary and a stated preference experiment with nine departure time choice scenarios. All psychological factors had a significant effect on departure time choice and could improve the model as compared to a basic discrete choice model without latent constructs. As expected, the effects of the psychological factors were different depending on framework conditions: for people with fixed starting times at work, the intention to arrive at work on time (as estimated by subjective norm, attitude, perceived behavioural control) had the strongest effect; for people with flexible working hours, the attitude towards short travel time was most relevant. Limitations, the inclusion of additional psychological factors and their possible interactions are discussed.     

Affective and cognitive attitudes,uncertainty avoidance and intention to obtain genetic testing: An extension of the Theory of Planned Behaviour

To ensure successful implementation of genetic screening and counselling according to patients best interests, the attitudes and motives of the public are important to consider. The aim of this study was to apply a theoretical framework in order to investigate which individual and disease characteristics might facilitate the uptake of genetic testing. A questionnaire using an extended version of the Theory of Planned Behaviour was developed to assess the predictive value of affective and cognitive expected outcomes, subjective norms, perceived control and uncertainty avoidance on the intention to undergo genetic testing. In addition to these individual characteristics, the predictive power of two disease characteristics was investigated by systematically varying the diseases fatality and penetrance (i.e. the probability of getting ill in case one is a mutation carrier). This resulted in four versions of the questionnaire which was mailed to a random sample of 2400 Norwegians. Results showed genetic test interest to be quite high, and to vary depending on the characteristics of the disease, with participants preferring tests for highly penetrant diseases. The most important individual predictor was uncertainty avoidance.     

The Effects of Social Identity and Perceived Autonomy Support on Health Behaviour Within the Theory of Planned Behaviour

The present study employed constructs from self-determination theory, social-identity theory, and the theory of planned behaviour to examine the combined effects that social identity and perceived autonomy support exerted on attitudes, intentions and health behaviour. A prospective design was employed measuring constructs from the theory of planned behaviour, group norms, group identification, and perceived autonomy support at baseline and physical activity behaviour 5 weeks later. Self-report questionnaires were administered to 231 pupils (male = 113, female = 118, M = 14.21 years, SD = .90). Hierarchical regression analysis demonstrated that group norms predicted participation in physical activities and attitudes, but only for participants who identified strongly with their group. Perceived autonomy support predicted attitudes, intentions and behaviour. The effects of perceived autonomy support and social-identity constructs were independent. It was concluded that both social identity and perceived autonomy support should be included in the theory of planned behaviour.     

Socioeconomic status as a moderator between social cognitions and physical activity: Systematic review and meta-analysis based on the Theory of Planned Behavior

BackgroundHealth inequalities are to a substantial degree due to socioeconomic status (SES) related differences in health behaviors such as physical activity. However, little is known about the role SES plays in the self-regulation of physical activity.PurposeThis systematic review with meta-analysis examines whether a comprehensive set of indicators of SES (income, education, occupational status) impacts on the behavioral self-regulation by moderating the relationships between social cognitions in the Theory of Planned Behavior (TPB) and physical activity.MethodsA systematic literature search identified 99 studies from 88 articles that provided information on sample SES and correlations between TPB variables and physical activity. Random-effects meta-analyses were used to pool correlations corrected for sampling and measurement error. Random-effects meta-regression was used to examine moderating effects of study-level SES on these correlations.ResultsEducation moderated the relationship between intentions and physical activity, such that studies with better educated samples reported stronger intention-physical activity relationships.ConclusionsThese results suggest that education might play a major role in the self-regulation of physical activity, with better educated samples more likely to translate intentions into behavior. This can both help to explain heterogeneity in the relation between intentions and physical activity as well as support the development of more effective interventions targeting intentions and physical activity.     

The adoption of physical activity and eating behaviors among persons with obesity and in the general population: the role of implicit attitudes within the Theory of Planned Behavior

Obesity can be prevented by the combined adoption of a regular physical activity (PA) and healthy eating behaviors (EB). Researchers mainly focused on socio-cognitive models, such as the Theory of Planned Behavior (TPB), to identify the psychological antecedents of these behaviors. However, few studies were interested in testing the potential contribution of automatic processes in the prediction of PA and EB. Thus, the main objective of this study was to explore the specific role of implicit attitudes in the pattern of prediction of self-reported PA and EB in the TPB framework, among persons with obesity and in adults from the general population. One hundred and fifty-three adults participated to this cross-sectional study among which 59 obese persons (74% women, age: 50.6 ± 12.3 years, BMI: 36.8 ± 4.03 kg m^–²) and 94 people from the general population (51% women; age: 34.7 ± 8.9 years). Implicit attitudes toward PA and EB were estimated through two Implicit Association Tests. TPB variables, PA and EB were assessed by questionnaire. Regarding to the prediction of PA, a significant contribution of implicit attitudes emerged in obese people, β = .25; 95%[CI: .01, .50]; P = .044, beyond the TPB variables, contrary to participants from the general population. The present study suggests that implicit attitudes play a specific role among persons with obesity regarding PA. Other studies are needed to examine which kind of psychological processes are specifically associated with PA and EB among obese people.     

Understanding Exercise and Diet Motivation in Overweight Women Enrolled in a Weight-Loss Program: A Prospective Study Using the Theory of Planned Behavior

The purpose of this study was to prospectively examine the utility of the theory of planned behavior (TPB) constructs for exercise and diet behavior with women enrolled in a 4-week weight-loss program. Sixty-nine females participated in group exercise 3 times a week and they consumed a low-calorie diet for 1 month. They completed baseline measures of exercise behavior, demographic variables, and the TPB constructs for exercise and diet at the start of the program. Adherence to the exercise and diet was recorded, along with pre- and post-measurements of body composition. Significant decreases in body mass index, body fat percentage, and circumference measurements occurred from pre- to post-program. Hierarchical multiple regression analyses revealed that diet adherence was predicted by intention. However, the TPB constructs failed to predict exercise adherence, exercise intention, and diet intention. These results are discussed in relationship to previous research, and recommendations for future studies with this special population are highlighted.