Gert-Jan de Bruijn

A Systematic Review and Meta-analysis of Applications of the Self-Report Habit Index to Nutrition and Physical Activity Behaviours

BackgroundHealth behaviour models typically neglect habitual action. The Self-Report Habit Index (SRHI) permits synthesis of evidence of the influence of habit on behaviour.PurposeThe purpose of this study is to review evidence around mean habit strength, habit–behaviour correlations, and habit × intention interactions, from applications of the SRHI to dietary, physical activity, and active travel behaviour.MethodElectronic database searches identified 126 potentially relevant papers. Twenty-two papers (21 datasets) passed eligibility screening. Mean scores and correlations were meta-analysed using fixed, random and mixed effects, and interactions were synthesised via narrative review.ResultsTwenty-three habit–behaviour correlations and nine habit × intention interaction tests were found. Typical habit strength was located around the SRHI midpoint. Weighted habit–behaviour effects were medium-to-strong (fixed: r+ = 0.44; random: r+ = 0.46). Eight tests found that habit moderated the intention–behaviour relation.ConclusionMore comprehensive understanding of nutrition and activity behaviours will be achieved by accounting for habitual responses to contextual cues.

Towards parsimony in habit measurement: Testing the convergent and predictive validity of an automaticity subscale of the Self-Report Habit Index

BackgroundThe twelve-item Self-Report Habit Index (SRHI) is the most popular measure of energy-balance related habits. This measure characterises habit by automatic activation, behavioural frequency, and relevance to self-identity. Previous empirical research suggests that the SRHI may be abbreviated with no losses in reliability or predictive utility. Drawing on recent theorising suggesting that automaticity is the ‘active ingredient’ of habit-behaviour relationships, we tested whether an automaticity-specific SRHI subscale could capture habit-based behaviour patterns in self-report data.MethodsA content validity task was undertaken to identify a subset of automaticity indicators within the SRHI. The reliability, convergent validity and predictive validity of the automaticity item subset was subsequently tested in secondary analyses of all previous SRHI applications, identified via systematic review, and in primary analyses of four raw datasets relating to energy‐balance relevant behaviours (inactive travel, active travel, snacking, and alcohol consumption).ResultsA four-item automaticity subscale (the ‘Self-Report Behavioural Automaticity Index’; ‘SRBAI’) was found to be reliable and sensitive to two hypothesised effects of habit on behaviour: a habit-behaviour correlation, and a moderating effect of habit on the intention-behaviour relationship.ConclusionThe SRBAI offers a parsimonious measure that adequately captures habitual behaviour patterns. The SRBAI may be of particular utility in predicting future behaviour and in studies tracking habit formation or disruption.

How big is the physical activity intention–behaviour gap? A meta-analysis using the action control framework

OBJECTIVES The physical activity (PA) intention-behaviour gap is a topic of considerable contemporary research, given that most of our models used to understand physical activity suggest that intention is the proximal antecedent of behavioural enactment. The purpose of this study was to quantify the intention-PA gap at public health guidelines with a meta-analysis of the action control framework. DESIGN Systematic review and meta-analysis. METHODS Literature searches were conducted in July 2012 among five key search engines. This search yielded a total of 2,865 potentially relevant records; of these, 10 studies fulfilled the full eligibility criteria (N = 3,899). RESULTS Random-effects meta-analysis procedures with correction for sampling bias were employed in the analysis for estimates of non-intenders who subsequently did not engage in physical activity (21%), non-intenders who subsequently performed physical activity (2%), intenders who were not successful at following through with their PA (36%), and successful intenders (42%). The overall intention-PA gap was 46%. CONCLUSION These results emphasize the weakness in early intention models for understanding PA and suggest this would be a problem during intervention. Contemporary research that is validating and exploring additional constructs (e.g., self-regulation, automaticity) that augment intention or improving the measurement of motivation seems warranted. STATEMENT OF CONTRIBUTION What is already known on this subject? Intention is considered the proximal antecedent of behaviour in many popular models. Intention is also an established correlate of physical activity behaviour, yet discordance is considerable in experimental research. What does this study add? This meta-analysis of studies that have assessed concordance/discordance of physical activity intention and behaviour at public health guidelines shows the intention-behaviour gap at 48% and the discordance is from intenders who do not act. The results demonstrate that discordance is not just from extreme levels of intention or behaviour (e.g., intend to exercise six times but only exercise five), but from levels that are relevant to health promotion.

Does habit strength moderate the intention-behaviour relationship in the Theory of Planned Behaviour? The case of fruit consumption

The present study examined if habit strength moderated the influence of intention on fruit consumption in a Dutch adult sample (N = 521, 46.3% males, mean age = 34.50, SD = 10.87), using the theoretical relations of the Theory of Planned Behaviour (TPB). TPB variables and habit strength were assessed at baseline. Fruit consumption was assessed with a validated questionnaire five weeks later. Three groups were created: low habit strength (n = 180), medium habit strength (n = 185) and high habit strength (n = 156). Confirmatory factor analyses and multi-group path analyses were performed using AMOS 4.0. A good fit was obtained for the overall measurement model and the structural models. Multi-group path analyses showed that intention was a significant predictor of fruit consumption in the low habit (β = 0.36, p < 0.001) and medium habit group (β = 0.30, p < 0.001), but a non-significant predictor in the high habit group (β = 0.05, p = 0.596). Implications for information-based and motivation-based interventions are discussed.

Adult active transportation: adding habit strength to the theory of planned behavior

BACKGROUND Many health behaviors have a history of repetition and, as a result, may become habitual. Because including a measure of habit strength may add depth to current theoretical models on health behavior, the present study explored the issue of habit strength within the context of the theory of planned behavior regarding adult bicycle use as a means of transportation. METHODS Cross-sectional data were gathered in a Dutch adult sample (n=317; mean age=42.09 years; 46.7% men) in 2006 using self-administered questionnaires. Variables for the theory of planned behavior were assessed regarding bicycle use as a means of transportation; habit strength regarding bicycle use as a means of transportation was assessed with the validated Self-Reported Habit Index. Hierarchical regression analyses and interaction analyses using simple slope analyses were conducted. RESULTS After controlling for variables for the theory of planned behavior, habit strength was the strongest predictor of bicycle use. In addition, simple slope analyses based on a significant interaction term, intention x habit, showed that intention was a significant predictor of bicycle use among those at low levels of habit strength for bicycle use (beta=0.67, p<0.001) but a weaker and nonsignificant predictor at high levels of habit strength (beta=0.10, p=0.136). CONCLUSIONS Habit strength is a moderator of the intention-behavior relationship regarding bicycle use, with intention becoming less relevant when bicycle use increases in habit strength. Future determinant and intervention studies on physical activity may benefit from including a measure of habit strength--for instance, by identifying the differential effects of informational and environmental interventions.

Interpersonal Communication as an Indirect Pathway for the Effect of Antismoking Media Content on Smoking Cessation

In the context of health campaigns, interpersonal communication can serve at least 2 functions: (a) to stimulate change through social interaction and (b) in a secondary diffusion process, to further disseminate message content. In a 3-wave prospective study of 1,079 smokers, the authors demonstrate that mass media messages (antismoking campaigns and news coverage relevant to smoking cessation) have an indirect effect on smoking cessation intention and behavior via interpersonal communication. Exposure to campaigns and news coverage prompts discussion about the campaigns, and, in turn, about smoking cessation. Interpersonal communication regarding smoking cessation then influences intention to quit smoking and attempts to quit smoking. The study finds evidence not only for the social interaction function of interpersonal communication, but also for the secondary diffusion function. A substantial number of smokers who are not directly exposed to the antismoking campaigns are nevertheless indirectly exposed via communication with people who have seen these campaigns. These results imply that encouragement of interpersonal communication can be an important campaign objective.

The effects of smoking self-identity and quitting self-identity on attempts to quit smoking

OBJECTIVE To examine the effect of two types of self-identity on attempts to quit smoking: self-identity in terms of smoking and self-identity in terms of quitting. DESIGN A prospective survey among an initial sample of 3,411 smokers. Smoking history variables and psychosocial variables from the theory of planned behavior are also measured. MAIN OUTCOME MEASURES Intention to quit smoking and smoking cessation attempts 4 months later. RESULTS Both smoking identity and quitting identity matter, but they appear to play different roles in explaining intention to quit and in predicting actual attempts to quit. Quitting identity is particularly important for intention to quit, whereas both quitting identity and smoking identity are important for actually trying to quit. Recent attempts to quit slightly attenuate the negative effect of smoking identity on attempts to quit. CONCLUSION A broader interpretation of self-identity in terms of both current and aspired behavior offers a better understanding of when people might change health-relevant behavior.

Saturated fat consumption and the Theory of Planned Behaviour: exploring additive and interactive effects of habit strength

The additive and interactive effects of habit strength in the explanation of saturated fat intake were explored within the framework of the Theory of Planned Behaviour (TPB). Cross-sectional data were gathered in a Dutch adult sample (n=764) using self-administered questionnaires and analyzed using hierarchical regression analyses and simple slope analyses. Results showed that habit strength was a significant correlate of fat intake (beta=-0.11) and significantly increased the amount of explained variance in fat intake (R(2-change)=0.01). Furthermore, based on a significant interaction effect (beta=0.11), simple slope analyses revealed that intention was a significant correlate of fat intake for low levels (beta=-0.29) and medium levels (beta=-0.19) of habit strength, but a weaker and non-significant correlate for high levels (beta=-0.07) of habit strength. Higher habit strength may thus make limiting fat intake a non-intentional behaviour. Implications for information and motivation-based interventions are discussed.

Adolescent soft drink consumption, television viewing and habit strength. Investigating clustering effects in the Theory of Planned Behaviour

Clustering refers to the co-occurrence of behaviour and may be particularly relevant in light of the present obesity epidemic. Since evidence regarding clustering of motivational and habitual constructs within the framework of the Theory of Planned Behaviour (TPB) is limited, clustering effects of TPB cognitions and habit strength regarding soft drink consumption and television viewing were studied in a sample of Dutch adolescents (n = 312; mean age = 14.62; SD = 1.62) using cross-sectional data. Results showed that not only soft drink consumption and television viewing cluster (r = .42), but also their intentional (r = .36) and habitual (r = .37) constructs. Furthermore, unmediated effects were found between habit strength and its respective behaviour, whereas habit strength was associated with its clustered behaviour through decreased perceptions of controllability. Our findings suggest that interventions that aim to change habitual soft drink consumption and television viewing may need to incorporate an environmental component, as well as explore the potential usefulness of synergistic effects of incorporating multiple clustered behaviours, as well as their corresponding beliefs and habits in health behaviour change interventions.Clustering refers to the co-occurrence of behaviour and may be particularly relevant in light of the present obesity epidemic. Since evidence regarding clustering of motivational and habitual constructs within the framework of the Theory of Planned Behaviour (TPB) is limited, clustering effects of TPB cognitions and habit strength regarding soft drink consumption and television viewing were studied in a sample of Dutch adolescents (n = 312; mean age = 14.62; SD = 1.62) using cross-sectional data. Results showed that not only soft drink consumption and television viewing cluster (r = .42), but also their intentional (r = .36) and habitual (r = .37) constructs. Furthermore, unmediated effects were found between habit strength and its respective behaviour, whereas habit strength was associated with its clustered behaviour through decreased perceptions of controllability. Our findings suggest that interventions that aim to change habitual soft drink consumption and television viewing may need to incorporate an environmental component, as well as explore the potential usefulness of synergistic effects of incorporating multiple clustered behaviours, as well as their corresponding beliefs and habits in health behaviour change interventions.

Automatic and Motivational Correlates of Physical Activity: Does Intensity Moderate the Relationship?

The purpose of this study was to examine the predictive capability of a habit construct, controlling for intention and perceived behavioral control, with moderate and strenuous intensity physical activity. This approach was expanded through an examination of whether conscious deliberation in the initiation of physical activity would attenuate these findings and a test of the intention-habit interaction. Participants were 337 undergraduate students who completed the habit measure and measures of intention, deliberation, and perceived behavioral control phrased in either moderate or vigorous intensities at time 1. This was followed by a measure of behaviour 2 weeks later. Results using stacked structural equation models (moderate and vigorous intensity) demonstrated the direct effect of habit and accounted for a significant effect on physical activity after controlling for intention and perceived behavioral control; this effect was invariant to intensity and conscious deliberation. A 3-way interaction, however, was identified for the habit X intention relationship and intensity. In the moderate intensity condition, individuals who reported higher habits showed a lower intention-behavior relationship when compared with those who reported modest or low habits. By contrast, individuals who reported high habit levels in the vigorous physical activity condition demonstrated a larger intention-behavior relationship than their modest and low habit counterparts. The results support the notions that some properties of physical activity may have an automatic component and that habits may be important to physical activity action initiation.