Depression and medication adherence among breast cancer survivors: bridging the gap with the theory of planned behaviour

Evidence suggests that more depressed breast cancer patients will less likely adhere to treatment plans. This study presents evidence that the theory of planned behaviour mediates the relation between depression and intentions to adhere to treatment plans and between depression and lack of adherence to medication regime. Two hundred and thirteen women undergoing breast cancer treatment participated in this study. Measures of depressive symptoms and planned behaviour variables were collected at the first time point; measures of medication adherence were collected at the second time point. Structural equation models were utilised to fit the data to the proposed models. Depressive symptoms were significantly correlated to both intentions and medication adherence. In support of hypotheses, the relation between depressive symptoms and treatment intention was mediated by attitudes towards health maintenance plans. The relation between depressive symptoms and medication adherence was fully mediated by the planned behaviour process. Conditions under which treatment intentions and perceptions of control in adhering to treatment were most related to medication adherence were elucidated. The results point to avenues for interventions to increase medication adherence among breast cancer patients. Manipulating attitudes and perceptions of control towards treatment plans will potentially serve to increase medication adherence.     

Predicting sun-protective intentions and behaviours using the theory of planned behaviour: a systematic review and meta-analysis

Objective: To synthesise theory of planned behaviour (TPB) relationships, using meta-analysis, and test the predictive utility of the model for sun protection behaviour.

Design: Thirty-eight samples were identified via database/manual searches and academic society posts based on the criteria: measuring sun-protective intentions and/or prospective behaviour; using the TPB/theory of reasoned action as a basis of measurement; and providing bivariate correlations for at least one relevant TPB association.

Main outcome measures: Sun-protective intentions and behaviours.

Results: The sample-weighted average effects were moderate-to-strong with attitudes showing the strongest association with intention (r+ = 0.494), followed by perceived behavioural control (PBC; r+ = 0.451), and subjective norm (r+ = 0.419). Intentions showed a stronger association with prospective behaviour (r+ = 0.486) compared to PBC (r+ = 0.314). A total of 39% of variance in intentions and 25% of variance in behaviour were explained. Publication bias was not evident. Moderator analyses showed that TPB associations were stronger when measures specified the Target, Action, Context and Time; in non-student samples; and when follow-up exceeded two weeks.

Conclusion: Despite recent criticism, this review shows that the TPB explains a large amount of variance in sun protection and that TPB associations are robust across different populations.     

Sleep hygiene behaviours: An application of the theory of planned behaviour and the investigation of perceived autonomy support,past behaviour and response inhibition

This study investigated the sleep hygiene behaviour of university students within the framework of the Theory of Planned Behaviour (TPB [Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50, 179–211.]), and examined the predictive validity of additional variables including perceived autonomy support, past behaviour and response inhibition. A total of 257 undergraduate students from an Australian university were administered two online questionnaires at two time points. At time 1, participants completed the TPB questionnaire and the Go/NoGo task as a measure of response inhibition. A week later at time 2, participants completed a questionnaire measuring the performance of sleep hygiene behaviours. Multiple and hierarchical regression analyses showed that the TPB model significantly predicted intention and behaviour. Although intention and perceived behavioural control were statistically significant in predicting behaviour, past behaviour and response inhibition accounted for more variance when added to the TPB model. Subjective norm was found to be the strongest predictor of intention implying the importance of normative influences in sleep hygiene behaviours. Response inhibition was the strongest predictor of behaviour, reinforcing the argument that the performance of health protective behaviours requires self-regulatory ability. Therefore, interventions should be targeted at enhancing self-regulatory capacity.     

Predictors of physical activity among rural and small town breast cancer survivors: An application of the theory of planned behaviour

The primary objective of this study was to investigate the utility of the two-component theory of planned behaviour (TPB) in understanding physical activity intentions and behaviour in rural and small town breast cancer survivors. The secondary objective was to elicit the most common behavioural, normative and control beliefs of rural and small town survivors regarding physical activity. Using a cross-sectional survey design, 524 rural and small town breast cancer survivors completed a mailed survey that assessed physical activity and TPB variables. Physical activity intention explained 12% of the variance in physical activity behaviour (p?相似文献   

Intentions to participate in counselling among front-line,at-risk Irish government employees: an application of the theory of planned behaviour

ABSTRACT

The study set out to examine intentions to engage in counselling among at-risk Irish government employees and the differential utility of two alternative theory of planned behaviour (TPB) models of behaviour to explain intentions to participate in counselling. Individuals (N=259) employed in a front-line, at-risk occupation for the Irish government completed a TPB-based questionnaire. Quantitative analyses revealed that participants held positive to neutral intentions to participate in counselling, irrespective of gender. The original TPB model explained 49.9% of variance in intentions whereas an alternative TPB model, splitting the perceived behavioural control (PBC) construct between its internal and external control components, explained a further 8.9% of variance. Furthermore, self-efficacy was found to be the strongest predictor of intentions. This study therefore supports the use of the TPB in understanding counselling-seeking behaviour.     

Predicting uptake of a routine cervical smear test: A comparison of the health belief model and the theory of planned behaviour

Abstract

This paper reports on a study carried out to identify predictors of uptake of cervical screening among 142 women (59% response rate) in inner London. Two social cognition models were used: The Health Belief Model (HBM; Becker, 1974) and the Theory of Planned Behaviour (TPB; Ajzen, 1991) and in addition anticipated affect following non-attendance for screening was assessed. The TPB emerged as by far the superior model for predicting screening intentions, explaining 51% of the variance in comparison with only 4% explained by the HBM variables. However, neither model was able to predict a significant amount of variance in uptake of screening three months later. Possible reasons for the poor prediction of this type of behaviour are discussed.     

Predictive validity of the theory of planned behaviour: the role of questionnaire format and social desirability

The present study was designed to assess the predictive validity of a theory of planned behaviour extended to include self‐identity, in the context of health‐related food choice. Following criticism of the use of questionnaires in social cognitive research, the impact of questionnaire format (random vs structured) and social desirability on questionnaire responses was assessed. Findings indicated that intention was the principal determinant of food choice; attitude, subjective norm and self‐identity were independently predictive of intention. There was only weak evidence to suggest effects of social desirability or questionnaire format on component relationships. The present study indicates that the impact of questionnaire format and social desirability on models such as the theory of planned behaviour is minimal, and that such models are robust predictors of food choice. Copyright © 1999 John Wiley & Sons, Ltd.     

Expectations of reducing fat intake: The role of perceived need within the theory of planned behaviour

Abstract

Dietary fat intake has been implicated in the causation of major diseases including coronary heart disease and cancer. Hence, current recommendatioris to improve health emphasise the reduction of fat intake (COMA, 1991). The present study investigated the effect of perceived need to reduce fat intake and past behaviour on peoples' expectations of reducing fat intake, using the framework of the Theory of Planned Behaviour (TPB) (Ajzen, 1985; 1991). The effects of estimated fat intake and body weight on perceived need to reduce were also investigated. One hundred and fifty-two adults completed a four-day weighed dietary record and completed a questionnaire based on the TPB. Perceived need to reduce fat intake, cognitive and affective components of attitude and past behaviour wm found to be significant predictors of expectation of reducing fat intake. Perceived body weight and estimated fat intake were significant predictors of perceived need to reduce fat intake. The implications of these findings for health promotion policy are discussed.     

Using the theory of planned behaviour to predict screening uptake in two contexts

Given current policy that decisions about screening should be based on informed choice, such decisions should reflect people's values and attitudes. This prospective study compares the attitudes and other cognitive predictors of screening uptake in two contexts: when conducted as part of a routine visit and when it is conducted at a separate, test-specific visit. It was conducted in two hospitals in England, differing in method of screening organisation. 1499 pregnant women offered serum screening for Down Syndrome completed a questionnaire assessing theory of planned behaviour constructs: attitude towards undergoing the test, subjective norms of others, perceived behavioural control and intention to undergo the test.

Intention predicted screening uptake in both screening settings, but more strongly when screening was part of a routine visit. Perceived behavioural control was not predictive of uptake, and only weakly predictive of intention in both settings. Subjective norm predicted intention more strongly when it referred to partner and friends than when it referred to health professionals, in both settings.

Attitude was more strongly predictive of intention to attend screening when screening was organised as a part of routine screening, rather than requiring a separate visit. These results suggest that offering a screening test at a routine visit compared with a separate visit is more likely to facilitated uninformed choices, given the stronger association between attitudes and intention and the absence of an association with the perceived influence of health professionals.     

Effects of action planning and coping planning within the theory of planned behaviour: A physical activity study of patients undergoing haemodialysis

Objective

Patients on dialysis have low physical activity levels. The aim of the study was to examine the validity of action planning and coping planning within the theory of planned behaviour framework, for predicting physical activity behaviour of patients on haemodialysis.

Design

This is a prospective study design.

Methods

One hundred and forty-four patients who were undergoing haemodialysis were selected from dialysis centres. The mean age of the patients was 56.61 (SD = 11.38) years. The patients completed a questionnaire including variables from the theory of planned behaviour, action planning and coping planning. Physical activity was prospectively assessed at 4-weeks with the validated International Physical Activity Questionnaire self-report measure. A hierarchical regression analysis was performed to examine the effects of action planning and coping planning on physical activity behaviour.

Results

There was a main effect for coping planning but not for action planning. Moreover, the analyses resulted in a significant amount of incremental variance accounted for by the interaction of coping planning and intention.

Conclusion

Results suggest the combination of high levels of coping planning and intention is associated with increases in physical activity.     

A pilot study on the motivational effects of an internet-delivered physical activity behaviour change programme in Nova Scotian cancer survivors

Objective: To examine the effects of an internet-delivered, distance-based physical activity (PA) behaviour change programme on motivation to perform PA in cancer survivors.

Design: Breast, prostate and colorectal cancer survivors (N = 95) were randomized to either an online Theory of Planned Behaviour (TPB)-based PA behaviour change programme (UCAN) or usual care.

Main Outcome Measures: Motivational variables from the TPB including intention, planning, attitude, subjective norm, perceived behavioural control and underlying beliefs.

Results: UCAN had significant negative effects on self-efficacy (?.7; 95% CI = ?1.2 to ?.1; d = ?.53, p = .019), affective attitude (?.4; 95% CI = ?.8 to ?.0; d = ?.45, p = .044), instrumental attitude (?.5; 95% CI = ?.9 to ?.1; d = ?.43, p = .026) and confidence to perform PA in bad weather (?.8; 95% CI = ?1.6 to ?.1; d = ?.49, p = .030), despite health issues (?.7; 95% CI = ?1.3 to ?.1; d = ?.48, p = .031), despite pain/soreness (?.7; 95% CI = ?1.4 to ?.1; d = ?.52, p = .020), despite family responsibilities (?1.0; 95% CI = ?1.7 to ?.3; d = ?.62, p = .005) and when PA is boring (?.8; 95% CI = ?1.4 to ?.1; d = ?.54, p = .016).

Conclusion: UCAN had negative effects on motivational variables in cancer survivors. These findings may be explained by methodological issues related to measuring motivation and/or the absence of post-intentional constructs.     

Integrating five-factor model facet-level traits with the theory of planned behavior and exercise

ObjectivesThe purpose of this study was to examine direct, indirect, and moderating links between facet-level personality traits of the five-factor model, the theory of planned behavior (TPB) constructs [Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50, 179–211.], and exercise behavior.DesignCross-sectional.MethodUniversity students (N = 507) completed the NEO-PI-R [Costa, P. T., McCrae, R. R. (1992). The NEO-PI-R personality inventory: Professional manual. Odessa, FL: Psychological Assessment Resources.], the Leisure-time Exercise Questionnaire [Godin, G., Shephard, R. J. (1985). A simple method to assess exercise behavior in the community. Canadian Journal of Applied Sport Science, 10, 141–146.], and measures assessing the TPB constructs.ResultsPreliminary analysis revealed the extraversion and conscientiousness facet-level traits of activity and self-discipline respectively were independent predictors of exercise behavior. An integrated structural model with both facet-level traits revealed that 46% of the variance in exercise behavior and 70% of the variance in intention was explained. Significant indirect effects of activity and self-discipline and the TPB constructs of affective attitude, instrumental attitude, and subjective norm, on exercise behavior through intention and perceived behavioral control were also observed. Finally, the anxiety facet trait of neuroticism significantly moderated the intention–behavior relationship.ConclusionsOur findings showed that the facet-level personality traits of activity and self-discipline are important motivational variables that link the TPB constructs to exercise behavior. Future research that integrates personality with the TPB within experimental interventions is warranted.     

The theory of planned behaviour and breast self-examination: assessing the impact of past behaviour, context stability and habit strength

This study applied the theory of planned behaviour (TPB) to the prediction of breast self-examination (BSE) intentions and behaviour, and tested whether the frequency of past behaviour and context stability moderates intention-behaviour and habit-behaviour relations. Seventy-seven females completed measures of the TPB, frequency of past behaviour, context stability and habit strength (Self-Report Habit Index). BSE behaviour was assessed at 1-month follow-up (n?=?66). The TPB explained 33% of the variance in BSE intentions and 11% of the variance in time 2 BSE. The frequency of past behaviour moderated the intention-behaviour relationship such that the intention was only positively related to time 2 BSE behaviour when the frequency of past behaviour was low. Context stability and the combination of the frequency of past behaviour?×?context stability moderated the habit-behaviour relationship such that habit strength was only positively related to time 2 BSE behaviour when context stability and the combination of frequency of past behaviour?×?context stability were high. The results are consistent with the proposal that behaviours that are performed frequently in stable contexts are predominantly under the control of habitual processes, whereas behaviours that are performed infrequently in unstable contexts are predominantly under the control of intentional processes.     

Psychological impact of breast cancer on the patient and the family: A clinical perspective

Breast cancer is the most frequently occurring cancer in women, with 182,000 new cases diagnosed in 1993. Breast cancer will strike a sizable percentage of women during the child-rearing years impacting, therefore, not only on the woman, but on the significant others in her life. This article explores the impact of breast cancer for the patient's life partner, parents, and children. A model intervention program for cancer patients with young children, piloted at the Derner Institute and developed in conjunction with the American Cancer Society, is also discussed.     

Peer support for women with breast cancer: the role of empathy and self‐disclosure

This study examined how women with breast cancer perceived different styles of peer helping. Forty recently diagnosed breast cancer patients evaluated three audiotaped conversations between a breast cancer patient and an (ex‐patient) volunteer helper; the conversations differed in terms of the empathy and self‐disclosure offered by the helper. The findings supported the first hypothesis, that a helping style involving high self‐disclosure would be positively evaluated only in the presence of high empathy. However, the findings did not support the second hypothesis, that in conversations where high empathy is present, a helping style involving high self‐disclosure would be evaluated more positively than one involving low self‐disclosure. Qualitative data suggested that the helper's ability to listen to the patient and the helper's appropriate sharing of her own experience of breast cancer were both perceived as important components of effective helping. Implications for the training and practice of volunteer helpers are discussed. Copyright © 1999 John Wiley & Sons, Ltd.     

Action-state orientation and the theory of planned behavior: A study of job search in China

Job search is an important element of people’s careers and is especially critical for unemployed individuals. The current study surveyed a sample of 328 unemployed job seekers in China to test hypotheses related to the theory of planned behavior and action-state orientation theory. Results of the three-wave longitudinal study demonstrated that the theory of planned behavior was effective in modeling job-search intention and job-search intensity. Action-state orientation moderated the relationship between attitude and intention, as well as the relationship between intention and intensity. The current study sheds light on the motivational and self-regulatory process of job search and reemployment for Chinese unemployed job seekers.     

Measuring illness representations in breast cancer survivors (BCS) prescribed tamoxifen: Modification and validation of the Revised Illness Perceptions Questionnaire (IPQ-BCS)

Objective: The Revised Illness Perceptions Questionnaire (IPQ-R), widely used to assess illness perceptions, may fail to measure unique characteristics of different illnesses. This study modified and validated the IPQ-R for breast cancer survivors to provide detailed understanding of the specific illness perceptions held by these patients.

Design: Initial modifications were made following qualitative interviews and were revised in a think-aloud study. The modified scale was tested in 753 breast cancer survivors prescribed tamoxifen. Modifications included adding a tamoxifen consequences scale and adapting the timeline scales to measure beliefs around risk of recurrence and cure. A confirmatory factor analysis was conducted on the modified questionnaire and an exploratory factor analysis on the causal beliefs scale. Test–retest reliability, internal consistency and construct validity were also examined.

Results: The proposed eight-factor structure showed acceptable model fit, with high loadings and good reliability for all subscales. Correlations between subscales were consistent with theory and previous research.

Conclusions: The IPQ-BCS is valid and reliable, and provides unique understanding of specific perceptions held by this population, including beliefs surrounding risk of recurrence and consequences of ongoing hormonal treatment. Identifying these perceptions will aid development of interventions targeting depression, fear of recurrence and medication non-adherence.     

Relationships among the theory of planned behavior,stages of change,and exercise behavior in older persons over a three year period

Abstract

The present study examined the relationships among the theory of planned behavior (TPB), stages of change, and exercise behavior in 131 older persons over a three year period. Participants completed a baseline questionnaire by mail that assessed attitude, perceived control, subjective norm, intention, and stage and then received a telephone call three years later in which current exercise stage and behavior were assessed. Path analyses showed that (a) TPB constructs were significant predictors of exercise stage, (b) intention mediated the effects of TPB constructs on exercise stage, and (c) exercise behavior was best predicted by intention rather than stage. Results were interpreted as providing evidence for the long term predictive validity of TPB in the exercise domain and as questioning the necessity of combining both intention and stage in a single predictive model.