Healthcare professionals' intentions and behaviours: A systematic review of studies based on social cognitive theories Psychosocial determinants of fruit and vegetable intake in adult population: a systematic review Promoting fruit and vegetable consumption. Testing an intervention based on the theory of planned behaviour Theory of planned behaviour cognitions do not predict self-reported or objective physical activity levels or change in the ProActive trial. Investigating theoretical explanations for behaviour change: The case study of ProActive Changes in BMI and blood pressure after a school based intervention: the CHILDREN study. Applying psychological theories to evidence-based clinical practice: Identifying factors predictive of managing upper respiratory tract infections without antibiotics Examining the theory‐effectiveness hypothesis: A systematic review of systematic reviews Applying psychological theories to evidence-based clinical practice: identifying factors predictive of placing preventive fissure sealants Attitudes to breastfeeding among adolescents. Effect of communicating genetic and phenotypic risk for type 2 diabetes in combination with lifestyle advice on objectively measured physical activity: protocol of a randomised controlled trial Theoretical integration in health psychology: unifying ideas and complementary explanations. Identifying effective behavioural components of Intervention and Comparison group support provided in SMOKing cEssation (IC-SMOKE) interventions: a systematic review protocol The theory of planned behaviour and healthy eating: Examining additive and moderating effects of social influence variables A theory-based process evaluation alongside a randomised controlled trial of printed educational messages to increase primary care physicians’ prescription of thiazide diuretics for hypertension [ISRCTN72772651] Testing a TheoRY-inspired MEssage ('TRY-ME'): a sub-trial within the Ontario Printed Educational Message (OPEM) trial Do brief online planning interventions increase physical activity amongst university students? A randomised controlled trial Pilot study of a brief intervention based on the theory of planned behaviour and self-identity to increase chlamydia testing among young people living in deprived areas. Habit, identity, and repetitive action: a prospective study of binge-drinking in UK students. Use of a time series design to test effectiveness of a theory-based intervention targeting adherence of health professionals to a clinical guideline. A causal modelling approach to the development of theory-based behaviour change programmes for trial evaluation. Impact of a physical activity intervention program on cognitive predictors of behaviour among adults at risk of Type 2 diabetes (ProActive randomised controlled trial) Interaction effects in the theory of planned behaviour: Predicting fruit and vegetable consumption in three prospective cohorts.
Background There is an important gap between the implication s of clinical research evidence and the routine clinical practice of healthcare professionals . Because individual decisions are often central to adoption of a clinical -related behaviour , more information about the cognitive mechanisms underlying behaviours is needed to improve behaviour change interventions targeting healthcare professionals . The aim of this study was to systematic ally review the published scientific literature about factors influencing health professionals ' behaviours based on social cognitive theories . These theories refer to theories where individual cognitions/thoughts are viewed as processes intervening between observable stimuli and responses in real world situations . Methods We search ed psycINFO , MEDLINE , EMBASE , CIHNAL , Index to theses , PROQUEST dissertations and theses and Current Contents for articles published in English only . We included studies that aim ed to predict healthcare professionals ' intentions and behaviours with a clear specification of relying on a social cognitive theory . Information on percent of explained variance ( R2 ) was used to compute the overall frequency-weighted mean R2 to evaluate the efficacy of prediction in several context s and according to different method ological aspects . The cognitive factors most consistently associated with prediction of healthcare professionals ' intention and behaviours were documented . Results Seventy eight studies met the inclusion criteria . Among these studies , 72 provided information on the determinants of intention and 16 prospect i ve studies provided information on the determinants of behaviour . The theory most often used as reference was the Theory of Reasoned Action ( TRA ) or its extension the Theory of Planned Behaviour ( TPB ) . An overall frequency-weighted mean R2 of 0.31 was observed for the prediction of behaviour ; 0.59 for the prediction of intention . A number of moderators influenced the efficacy of prediction ; frequency-weighted mean R2 varied from 0.001 to 0.58 for behaviour and 0.19 to 0.81 for intention . Conclusion Our results suggest that the TPB appears to be an appropriate theory to predict behaviour whereas other theories better capture the dynamic underlying intention . In addition , given the variations in efficacy of prediction , special care should be given to method ological issues , especially to better define the context of behaviour performance Background Accumulating evidence suggests that fruit and vegetable intake ( FVI ) plays a protective role against major diseases . Despite this protective role and the obesity p and emic context , population s in Western countries usually eat far less than five servings of fruits and vegetables per day . In order to increase the efficiency of interventions , they should be tailored to the most important determinants or mediators of FVI . The objective was to systematic ally review social cognitive theory-based studies of FVI and to identify its main psychosocial determinants . Methods Published papers were systematic ally sought using Current Contents ( 2007 - 2009 ) and Medline , Embase , PsycINFO , Proquest and Thesis , as well as Cinhal ( 1980 - 2009 ) . Additional studies were identified by a manual search in the bibliographies . Search terms included fruit , vegetable , behaviour , intention , as well as names of specific theories . Only studies predicting FVI or intention to eat fruits and vegetables in the general population and using a social cognitive theory were included . Independent extraction of information was carried out by two persons using predefined data fields , including study quality criteria . Results A total of 23 studies were identified and included , 15 study ing only the determinants of FVI , seven study ing the determinants of FVI and intention and one study ing only the determinants of intention . All pooled analyses were based on r and om-effects models . The r and om-effect R2 observed for the prediction of FVI was 0.23 and it was 0.34 for the prediction of intention . Multicomponent theoretical frameworks and the theory of planned behaviour ( TPB ) were most often used . A number of method ological moderators influenced the efficacy of prediction of FVI . The most consistent variables predicting behaviour were habit , motivation and goals , beliefs about capabilities , knowledge and taste ; those explaining intention were beliefs about capabilities , beliefs about consequences and perceived social influences . Conclusions Our results suggest that the TPB and social cognitive theory ( SCT ) are the preferable social cognitive theories to predict behaviour and TPB to explain intention . Efficacy of prediction was nonetheless negatively affected by method ological factors such as the study design and the quality of psychosocial and behavioural measures This study evaluated the efficacy of a theory of planned behaviour ( TPB ) based intervention to increase  fruit and vegetable consumption .  The extent to which fruit and vegetable consumption and change in intake could be explained by the TPB was also examined . Participants were r and omly assigned to two levels of intervention frequency matched for intervention content ( low frequency n=92 , high frequency n=102 ) . Participants received TPB-based email messages design ed to increase fruit and vegetable consumption , messages targeted attitude , subjective norm and perceived behavioural control ( PBC ) . Baseline and post-intervention measures of  TPB variables and behaviour were collected . Across the entire study cohort , fruit and vegetable consumption increased by 0.83 servings/day between baseline and follow-up . Intention , attitude , subjective norm and PBC also increased ( p<.05 ) . The TPB successfully modelled fruit and vegetable consumption at both time points but not behaviour change . The increase of fruit and vegetable consumption is a promising preliminary finding for those primarily interested in increasing fruit and vegetable consumption . However , those interested in theory development may have concerns about the use of this model to explain behaviour change in this context . More high quality experimental tests of the theory are needed to confirm this result OBJECTIVE The objective was to test , in a trial cohort of sedentary adults at risk of Type 2 diabetes , whether theory of planned behaviour ( TPB ) cognitions about becoming more physically active predicted objective and self-reported activity levels and change . DESIGN Participants of a r and omized controlled trial underwent measurement at baseline , 6 and 12 months . METHODS Participants ( N= 365 , 30 - 50 years ) were recruited via their parent or family history registers at 20 general practice s in the UK .  Energy expenditure was measured objective ly at baseline and 1 year . Participants completed question naires assessing physical activity and beliefs about becoming more physically active over the next year at baseline , 6 and 12 months . RESULTS Between baseline and 12 months , objective energy expenditure in the cohort increased by an average of 20 minutes of brisk walking per day . Based on the 252 participants who provided complete data , affective attitude and perceived behavioural control consistently predicted intention , but intention and perceived behavioural control failed to predict physical activity levels or change ( p-values > .05 ) . CONCLUSIONS Failure of the theory to predict behaviour and behaviour change may be due to inapplicability of the theory to this at-risk population or to trial participation and intensive measurement facilitating behaviour change without affecting measured cognitions , or lack of correspondence between cognitive and behavioural measures . A wide range of potential personal and environmental mediators should be considered when design ing physical activity interventions among at-risk groups . High- quality experimental tests of the theory are needed in clinical population Developing more effective behavioural interventions requires an underst and ing of the mechanisms of behaviour change , and methods to rigorously test their theoretical basis . The delivery and theoretical basis of an intervention protocol were assessed in ProActive , a UK trial of an intervention to increase the physical activity of those at risk of Type 2 diabetes ( N = 365 ) . In 108 intervention sessions , behaviours of facilitators were mapped to four theories that informed intervention development and behaviours of participants were mapped to 17 theoretical components of these four theories . The theory base of the intervention specified by the protocol was different than that delivered by facilitators , and that received by participants . Of the intervention techniques delivered , 25 % were associated with  theory of planned behaviour ( TPB )  , 42 % with  self-regulation theory ( SRT )  , 24 % with  operant learning theory ( OLT )  and 9 % with  relapse prevention theory ( RPT ) .  The theoretical classification of participant talk showed a different pattern , with twice the proportion associated with OLT ( 48 % ) , 21 % associated with TPB , 31 % with SRT and no talk associated with RPT . This study demonstrates one approach to assessing the extent to which the theories used to guide intervention development account for any changes observed BACKGROUND Identification of the behavioural , normative and control beliefs influencing children 's behaviour is an important prerequisite in design ing effective interventions . The current study aims to evaluate the effectiveness of an intervention program , based on the Theory of Planned Behaviour ( TPB ) , on  obesity indices and blood pressure ( BP ) in Ioannina , Greece . METHODS Participants were 646 fifth grade pupils ( 360 girls and 286 boys ) . The intervention group ( IG ) consisted of 321 children in 13 r and omly selected schools while the rest ( n = 325 children ) served as the  control group ( CG ) . Based on the outcome of the TPB question naire , the intervention focused on overcoming the barriers in accessing physical activity areas , increasing the availability of fruits and vegetables and increasing parental support . General linear mixed model and mediating variable analysis were used to evaluate the differences between the two groups and to test whether changes in certain dietary , physical activity and anthropometrical indices mediated the effect of the intervention on BP . RESULTS IG had higher consumption of fruits and lower consumption of fats/oils and sweets/beverages compared with the CG . Intervention 's effect on BMI could be explained by the changes in fruit and fats/oils intake whereas the reduction of systolic and diastolic BP could be explained by the reduction of BMI . CONCLUSIONS The findings indicate favourable changes in BP and obesity indices after the implementation of a 1-year school-based intervention program based on the TPB . These results highlight the importance of developing a social and physical environment that promotes balanced eating behaviours and extra-curricular access to physical activity venues Background Psychological models can be used to underst and and predict behaviour in a wide range of setting s. However , they have not been consistently applied to health professional behaviours , and the contribution of differing theories is not clear . The aim of this study was to explore the usefulness of a range of psychological theories to predict health professional behaviour relating to management of upper respiratory tract infections ( URTIs ) without antibiotics . Methods Psychological measures were collected by postal question naire survey from a r and om sample of general practitioners ( GPs ) in Scotl and . The outcome measures were clinical behaviour ( using antibiotic prescription rates as a proxy indicator ) ,  behavioural simulation ( scenario-based decisions to managing URTI with or without antibiotics ) and behavioural intention ( general intention to managing URTI without antibiotics ) . Explanatory variables were the constructs within the following theories : Theory of Planned Behaviour ( TPB ) , Social Cognitive Theory ( SCT ) , Common Sense Self-Regulation Model ( CS-SRM ) , Operant Learning Theory ( OLT ) , Implementation Intention ( II ) , Stage Model ( SM ) , and knowledge ( a non-theoretical construct ) . For each outcome measure , multiple regression analysis was used to examine the predictive value of each theoretical model individually . Following this ' theory level ' analysis , a ' cross theory ' analysis was conducted to investigate the combined predictive value of all significant individual constructs across theories . Results All theories were tested , but only significant results are presented . When predicting behaviour , at the theory level , OLT explained 6 % of the variance and , in a cross theory analysis , OLT ' evidence of habitual behaviour ' also explained 6 % . When predicting  behavioural simulation  , at the theory level , the proportion of variance explained was : TPB , 31 % ; SCT , 26 % ; II , 6 % ; OLT , 24 % . GPs who reported having already decided to change their management to try to avoid the use of antibiotics made significantly fewer scenario-based decisions to prescribe . In the cross theory analysis , perceived behavioural control ( TPB ) , evidence of habitual behaviour ( OLT ) , CS-SRM cause ( chance/bad luck ) , and intention entered the equation , together explaining 36 % of the variance . When predicting intention , at the theory level , the proportion of variance explained was : TPB , 30 % ; SCT , 29 % ; CS-SRM 27 % ; OLT , 43 % . GPs who reported that they had already decided to change their management to try to avoid the use of antibiotics had a significantly higher intention to manage URTIs without prescribing antibiotics . In the cross theory analysis , OLT evidence of habitual behaviour , TPB attitudes , risk perception , CS-SRM control by doctor , TPB perceived behavioural control and CS-SRM control by treatment entered the equation , together explaining 49 % of the variance in intention . Conclusion The study provides evidence that psychological models can be useful in underst and ing and predicting clinical behaviour . Taking a theory-based approach enables the creation of a replicable methodology for identifying factors that predict clinical behaviour . However , a number of conceptual and method ological challenges remain PURPOSE Health interventions based on theory may be more effective than those that are not . This review of review s synthesizes all published r and omized controlled trial ( RCT ) meta-analytic evidence from the last decade to examine whether theory-based interventions were found to be associated with more effective  adult health behaviour change interventions . METHODS Systematic review s including meta-analyses were identified by search ing Medline , CINAHL , PsycINFO , and CDSR . A narrative synthesis was used to summarize and analyse the evidence . Only review s including RCTs of health behaviour change interventions with adults aged 18 + published from 2007 to 2017 were included . RESULTS Of 8,659 articles , nine systematic review s met inclusion criteria . The majority of review s ( n = 8) suggested no increased effectiveness for theory-based compared to non-theory-based interventions for effectiveness of outcomes relating to health behaviour . Less than half of the RCTs included in the review s reported the use of theory ( 85/183 ) . Two review s suggested interventions based on control theory , motivational interviewing , or self-determination theory were associated with greater effectiveness for physical activity and /or dietary interventions and outcomes . Method ological and reporting issues limit the conclusions . CONCLUSIONS Theory-based interventions as currently operationalized in systematic review s were not found to be more effective than non-theory-based interventions . Method ological and reporting issues at study and review level may not reflect the true utility of theory use within health behaviour interventions . The promotion of theory use may benefit from using a multifaceted argument , rather than a narrow focus of increased effectiveness . Statement of contribution What is already known on this subject ? Theory use is regularly promoted by cl aim ing that it will lead to more effective behaviour change interventions . Theory use has been frequently linked to effectiveness within systematic review s of behaviour change interventions . The theory-effectiveness hypothesis has not been systematic ally examined at the systematic review level . What does this study add ? Theory use as operationalized by systematic review authors was not associated with increased effectiveness within systematic review s examining r and omized controlled trials of behaviour change interventions in adults . Interventions based on control theory , motivational interviewing , or self-determination theory were associated with greater effectiveness for physical activity and /or dietary interventions and outcomes . Theory use should be promoted using a multifaceted argument , and assertions for increased effectiveness of theory-based interventions should only be used in domains where specific evidence exists to support this cl aim Background Psychological models are used to underst and and predict behaviour in a wide range of setting s , but have not been consistently applied to health professional behaviours , and the contribution of differing theories is not clear . This study explored the usefulness of a range of models to predict an evidence -based behaviour -- the placing of fissure sealants . Methods Measures were collected by postal question naire from a r and om sample of general dental practitioners ( GDPs ) in Scotl and . Outcomes were  behavioural simulation ( scenario decision-making )  , and behavioural intention .  Predictor variables were from the Theory of Planned Behaviour ( TPB ) , Social Cognitive Theory ( SCT ) , Common Sense Self-regulation Model ( CS-SRM ) , Operant Learning Theory ( OLT ) , Implementation Intention ( II ) , Stage Model , and knowledge ( a non-theoretical construct ) . Multiple regression analysis was used to examine the predictive value of each theoretical model individually . Significant constructs from all theories were then entered into a ' cross theory ' stepwise regression analysis to investigate their combined predictive value Results Behavioural simulation - theory level variance explained was : TPB 31 % ; SCT 29 % ; II 7 % ; OLT 30 % . Neither CS-SRM nor stage explained significant variance . In the cross theory analysis , habit ( OLT ) , timeline acute ( CS-SRM ) , and outcome expectancy ( SCT ) entered the equation , together explaining 38 % of the variance . Behavioural intention - theory level variance explained was : TPB 30 % ; SCT 24 % ; OLT 58 % , CS-SRM 27 % . GDPs in the action stage had significantly higher intention to place fissure sealants . In the cross theory analysis , habit ( OLT ) and attitude ( TPB ) entered the equation , together explaining 68 % of the variance in intention . Summary The study provides evidence that psychological models can be useful in underst and ing and predicting clinical behaviour . Taking a theory-based approach enables the creation of a replicable methodology for identifying factors that may predict clinical behaviour and so provide possible targets for knowledge translation interventions . Results suggest that more evidence -based behaviour may be achieved by influencing beliefs about the positive outcomes of placing fissure sealants and building a habit of placing them as part of patient management . However a number of conceptual and method ological challenges remain BACKGROUND Breastfeeding is a major public health concern and a decision to breastfeed has important health benefits for both the infant and mother . Breastfeeding rates are low in many Western countries , and evidence is accumulating to suggest that breastfeeding should be promoted in schools . The present study aim ed to employ the theory of planned behaviour ( TPB ) to predict and explain young people 's motivations to breastfeed with a view to design ing an intervention to positively promote breastfeeding among adolescents . METHODS Senior schools in Northern Irel and were sorted by a number of key stratification variables , and then r and omly sample d. In anticipation of a nonresponse , a first and second reserve list was drawn using matched replacements . Selected schools were contacted by letter , followed by a telephone call . Thirty-six schools agreed to take part in the research , and a cross-sectional survey was conducted with 2021 Year 10 pupils . RESULTS Having been breastfed as a child and having seen a mother breastfeeding significantly correlated with intention among both females and males . In descending order of importance , the TPB direct constructs were all significantly correlated with intention among males and females . A hierarchical multiple regression was performed with the intention to breastfeed/encourage partner to breastfeed as the dependent variable , and the TPB successfully predicted intention among males and females . CONCLUSIONS The findings obtained in the present study suggest that the TPB is a useful framework on which to base the design of an intervention to promote attitude change , and highlight the importance of key theoretical constructs in predicting intentions to breastfeed Type 2 diabetes ( T2D ) is associated with increased risk of morbidity and premature mortality . Among those at high risk , incidence can be halved through healthy changes in behaviour . Information about genetic and phenotypic risk of T2D is now widely available . Whether such information motivates behaviour change is unknown . We aim to assess the effects of communicating genetic and phenotypic risk of T2D on risk-reducing health behaviours , anxiety , and other cognitive and emotional theory-based antecedents of behaviour change . In a parallel group , open r and omised controlled trial , approximately 580 adults born between 1950 and 1975 will be recruited from the on-going population -based , observational Fenl and Study ( Cambridgeshire , UK ) . Eligible participants will have undergone clinical , anthropometric , and psychosocial measurements , been genotyped for 23 single-nucleotide polymorphisms associated with T2D , and worn a combined heart rate monitor and accelerometer ( Actiheart ® ) continuously for six days and nights to assess physical activity .  Participants are r and omised to receive either st and ard lifestyle advice alone ( control group ) , or in combination with a genetic or a phenotypic risk estimate for T2D ( intervention groups ) . The primary outcome is objective ly measured physical activity . Secondary outcomes include self-reported diet , self-reported weight , intention to be physically active and to engage in a healthy diet , anxiety , diabetes-related worry , self-rated health , and other cognitive and emotional outcomes . Follow-up occurs eight weeks post-intervention . Values at follow-up , adjusted for baseline , will be compared between r and omised groups . This study will provide much needed evidence on the effects of providing information about the genetic and phenotypic risk of T2D . Importantly , it will be among the first to examine the impact of genetic risk information using a r and omised controlled trial design , a population -based sample , and an objective ly measured behavioural outcome . Results of this trial , along with recent evidence syntheses of similar studies , should inform policy concerning the availability and use of genetic risk information . Current Controlled Trials IS RCT Theoretical approaches to behaviour change are now pervasive in the health psychology literature ( Abraham & Michie , 2008 ; Michie , Johnston , Francis , Hardeman , & Eccles , 2008 ) . Many are developed in the social psychology literature and applied in health context s to provide a hypothesis-testing framework for empirical investigations into health behaviours and outcomes ( Michie , Rothman , & Sheeran , 2007 ) . Numerous theoretical perspectives have been applied in the health sphere : the health action process model ( Schwartzer , 1992 ) , the health belief model ( Becker , 1974 ) , protection motivation theory ( PMT ; Rogers , 1975 ) , self-determination theory ( Deci & Ryan , 1985 ) , self-regulation theory ( Leventhal , Leventhal , & Contrada , 1998 ) , social cognitive theory ( B and ura , 1977 ) , subjective expected utility theory ( Edwards , 1954 ) , the theories of reasoned action ( Ajzen & Fishbein , 1980 ) and planned behaviour ( Ajzen , 1985 ) , the theory of interpersonal behaviour ( Tri and is , 1977 ) , and the transtheoretical model ( Prochaska & DiClemente , 1982 ) to name but a few . While meta-analytic review s of cross-sectional , prospect i ve , experimental , and intervention studies have indicated that these theories have varying degrees of utility in explaining variance in health behaviour and outcomes ( Armitage & Conner , 2001 ; Hardeman et al. , 2002 ; Milne , Sheeran , & Orbell , 2000 ; Sibley & Abraham , 2008 ) , a substantial variance in health behaviour remains unexplained ( Ogden , 2003 ; Weinstein , 2007 ) . There is a further problem ; when the impact of past behaviour or previous experience is accounted for , the efficacy of the theories in explaining health behaviour tends to fall dramatically ( Hagger , Chatzisarantis , & Biddle , 2002 ; Sutton , 1994 ) . This makes the identification of the psychological constructs that account for behaviour uniquely and independent of past behaviour paramount . Furthermore , theories of health behaviour have become increasingly complex , with additional variables being incorporated as additional predictors , mediators , or moderators to test , with increasing detail , the limitations and boundaries of each theory ( Ajzen , 1998 ; Armitage & Conner Background Systematic review s of behaviour change interventions for  smoking cessation  vary in scope , quality , and applicability . The current review aims to generate more accurate and useful findings by ( 1 ) a detailed analysis of intervention elements that change behaviour ( i.e. behaviour change techniques ( BCTs ) ) and potential moderators of behaviour change ( i.e. other intervention and sample characteristics ) and ( 2 ) assessing and controlling for variability in support provided to comparison groups in smoking cessation trials . Methods A systematic review will be conducted of r and omized controlled trials of behaviour change interventions for smoking cessation in adults ( with or without pharmacological support ) , with a minimum follow-up of 6 months , published after 1995 . Eligible articles will be identified through the Cochrane Tobacco Addiction Group Specialized Register . Study authors will be asked for detailed descriptions of smoking cessation support provided to intervention and comparison groups . All data will be independently coded by two research ers . The BCT taxonomy v1 ( tailored to smoking cessation interventions ) and template for intervention description and replication criteria will be used to code intervention characteristics . Data collection will further include sample and trial characteristics and outcome data ( smoking cessation rates ) . Multilevel mixed-effects meta-regression models will be used to examine which BCTs and /or BCT clusters delivered to intervention and comparison groups explain smoking cessation rates in treatment arms ( and effect sizes ) and what key moderators of behaviour change are . Predicted effect sizes of each intervention will be computed assuming all interventions are compared against comparison groups receiving the same levels of behavioural support ( i.e. low , medium , and high levels ) . Multi-disciplinary advisory board members ( policymakers , health care providers , and (ex-)smokers ) will provide strategic input throughout the project to ensure the review ’s applicability to policy and practice . Discussion By capturing BCTs in intervention and comparison groups , this systematic review will provide more accurate estimates of the effectiveness of smoking cessation interventions , the most promising BCTs and /or BCT clusters associated with smoking cessation rates in intervention and comparison arms , and important moderators of behaviour change . The results could set new st and ards for conducting meta-analyses of behaviour change interventions and improve research , service delivery , and training in the area of smoking cessation . Systematic review registration PROSPERO Abstract This paper examines the additive and moderating effects of social influence variables ( injunctive norms , descriptive norms , perceived social support ) within the Theory of Planned Behaviour ( TPB ) . The target behaviour is the decision to eat healthily . Question naire responses on components of the TPB , descriptive norms , perceived social support  , and subsequent healthy eating were obtained from a prospect i ve sample of 235 members of the general public . Good predictions of intentions ( 42 % of variance explained ) and behaviour ( 15 % of variance explained ) were found using the Theory of Planned Behaviour . Neither descriptive norms nor perceived social support added to these predictions of intentions over and above the TPB variables . However , perceived social support was found to act as a moderator variable on the relationship between perceived behavioral control and intention , and the relationship between attitude and intention . Implication s for exploring the role of social influence variables on decisions concerning health behavioun an discussed Background Pragmatic trials of implementation interventions focus on evaluating whether an intervention changes professional behaviour under real-world conditions rather than investigating the mechanism through which change occurs . Theory-based process evaluations conducted alongside pragmatic r and omised trials address this by assessing whether the intervention changes theoretical constructs proposed to mediate change . The Ontario Printed Educational Material s ( PEM ) cluster trial was design ed to increase family physicians ’ guideline -recommended prescription of thiazide diuretics . The trial found no intervention effect . Using the theory of planned behaviour ( TPB ) , we hypothesised that changes in thiazide prescribing would be reflected in changes in intention , consistent with changes in attitude and subjective norm , with no change to their perceived behavioural control ( PBC ) , and tested this alongside the RCT . Methods We developed and sent TPB postal question naires to a r and om sub- sample of family physicians in each trial arm 2 months before and 6 months after dissemination of the PEMs . We used analysis of covariance to test for group differences using a 2 × 3 factorial design . We content-analysed an open-ended question about perceived barriers to thiazide prescription . Using control group data , we tested whether baseline measures of TPB constructs predicted self-reported thiazide prescribing at follow-up . Results Four hundred twenty-six physicians completed pre- and post-intervention question naires . Baseline scores on measures of TPB constructs were high : intention mean = 5.9 out of 7 ( SD = 1.4 ) , attitude mean = 5.8 ( SD = 1.1 ) , subjective norm mean = 5.8 ( SD = 1.1 ) and PBC mean = 6.2 ( SD = 1.0 ) . The arms did not significantly differ post-intervention on any of the theory-based constructs , suggesting a possible ceiling effect . Content analysis of perceived barriers suggested post-intentional barriers to prescribing thiazides most often focused on specific patient clinical characteristics and potential side effects . Baseline intention ( β = 0.63 , p < 0.01 ) but not PBC ( β = 0.04 , p = 0.78 ) predicted 42.6 % of the variance in self-reported behaviour at follow-up in the control group . Conclusions Congruent with the Ontario Printed Educational Messages trial results and aligned with the TPB , we saw no impact of the intervention on any TPB constructs . The theoretical basis of this evaluation suggests possible explanations for the failure of the PEM intervention to change professional behaviour , which can directly inform the design and content of future theory-based PEM interventions to change professional behaviour . Trial registration IS RCT N , Canada IS RCT Background A challenge for implementation research ers is to develop principles that could generate testable hypotheses that apply across a range of clinical context s , thus leading to generalisability of findings . Such principles may be provided by systematic ally developed theories . The opportunity has arisen to test some of these theoretical principles in the Ontario Printed Educational Material s ( OPEM ) trial by conducting a sub-trial within the existing trial structure . OPEM is a large factorial cluster-r and omised trial evaluating the effects of short directive and long discursive educational messages embedded into informed , an evidence -based newsletter produced in Canada by the Institute for Clinical Evaluative Sciences ( ICES ) and mailed to all primary care physicians in Ontario . The content of educational messages in the sub-trial will be constructed using both st and ard methods and methods inspired by psychological theory . The aim of this study is to test the effectiveness of the  TheoRY-inspired MEssage ( ' TRY-ME '  ) compared with the ' st and ard ' message in changing prescribing behaviour . Methods The OPEM trial participants r and omised to receive the short directive message attached to the outside of informed(an ' outsert ' )  will be sub-r and omised to receive either a st and ard message or a message informed by the theory of planned behaviour ( TPB ) using a two ( long insert or no insert ) by three ( theory-based outsert or st and ard outsert or no outsert ) design . The messages will relate to prescription of thiazide diuretics as first line drug treatment for hypertension ( described in the accompanying protocol , " The Ontario Printed Educational Material s trial " ) . The short messages will be developed independently by two research teams . The primary outcome is prescription of thiazide diuretics , measured by routinely collected data available within ICES . The study is design ed to answer the question , is there any difference in guideline adherence ( i.e. , thiazide prescription rates ) between physicians in the six groups ? A  process evaluation survey instrument based on the TPB will be administered pre- and post-intervention ( described in the accompanying protocol , " Looking inside the black box " ) . The second research question concerns processes that may underlie observed differences in prescribing behaviour . We expect that effects of the messages on prescribing behaviour will be mediated through changes in physicians ' cognitions . Trial registration numberCurrent controlled trial IS RCT Brief planning interventions , usually delivered within paper and pencil question naires , have been found to be effective in changing health behaviours . Using a double-blind r and omised controlled trial , this study examined the efficacy of two types of planning interventions ( action plans and coping plans ) in increasing physical activity levels when they are delivered via the internet . Following the completion of self-reported physical activity ( primary outcome ) and theory of planned behaviour ( TPB ) measures at baseline , students ( N = 1273 ) were r and omised into one of four conditions on the basis of a 2 ( received instructions to form action plans or not ) × 2 ( received instructions to form coping plans or not ) factorial design . Physical activity ( primary outcome ) and TPB measures were completed again at two-month follow-up . An objective measure ( attendance at the university 's sports facilities ) was employed 6 weeks after a follow-up for a duration of 13 weeks ( secondary outcome ) . The interventions did not change self-reported physical activity , attendance at campus sports facilities or TPB measures . This might be due to low adherence to the intervention protocol ( ranging from 58.8 to 76.7 % ) . The results of this study suggest that the planning interventions under investigation are ineffective in changing behaviour when delivered online to a sample of participants unaware of the allocation to different conditions . Possible moderators of the effectiveness of planning interventions in changing health behaviours are discussed OBJECTIVES This study sought to estimate the effects of a novel intervention , compared with usual chlamydia testing promotion , on chlamydia test uptake and intentions among young people living in deprived areas . The intervention was based on the theory of planned behaviour , augmented with self-identity , and targeted the significant predictors of chlamydia testing intentions identified in the previous research . METHODS Cluster r and omization was used to allocate college tutor groups ( intervention n = 10 ; control n = 11 ) to the intervention or control group . The sample comprised 253 participants ( intervention n = 145 , control n = 108 ) . The primary outcome was test offer uptake at the end of the session . Other outcomes measured at immediate follow-up were intention , attitude , subjective norm , perceived behavioural control , and self-identity . RESULTS Generalized estimating equations , controlling for cluster effects and sexual activity , found a small but non-significant effect of condition on test offer uptake , OR = 1.65 ( 95 % CI 0.70 , 3.88 ) p = .25 , with 57.5 % of intervention participants accepting the offer of a test compared with 40.2 % of control participants . Using the same analysis procedure , small-to-medium intervention effects were found on other outcome variables , including a significant effect on attitudes towards chlamydia testing , OR = 1.37 ( 95 % CI 1.00 , 1.87 ) , p = .05 . CONCLUSIONS The results provide encouraging initial evidence that this theory-based intervention , targeting the key determinants of chlamydia testing , may help to improve chlamydia testing uptake in a high-risk group . They support the conduct of a larger trial to evaluate the effectiveness of the intervention . STATEMENT OF CONTRIBUTION What is already known on this subject ? Young people living in areas of increased socio-economic deprivation have been identified as a high-risk group for chlamydia . Previous research within an extended model of the theory of planned behaviour ( TPB ) found that attitude , subjective norm , perceived behavioural control , and self-identity all significantly predicted chlamydia testing intentions in this high-risk group . What does this study add ? Development and testing of a novel , TPB-based intervention targeting predictors of chlamydia testing intentions . The intervention led to significantly more positive attitudes towards chlamydia testing . Preliminary indication that a TPB-based intervention may help to improve chlamydia testing in a high-risk group OBJECTIVES Repeated action can lead to the formation of habits and identification as ' the kind of person ' that performs the behaviour . This has led to the suggestion that identity- relevance is a facet of habit . This study explores conceptual overlap between habit and identity , and examines where the two constructs fit into an extended Theory of Planned Behaviour ( TPB ) model of binge-drinking among university students . DESIGN Prospect i ve , question naire-based correlational design . METHODS A total of 167 UK university students completed baseline measures of past behaviour , self-identity , the Self-Report Habit Index ( SRHI ) , and TPB constructs . One week later , 128 participants completed a follow-up behaviour measure . RESULTS Factor analyses of the SRHI and four identity items revealed two correlated but distinct factors , relating to habit and identity , respectively . Hierarchical regression analyses of intention and behaviour showed that identity contributed over and above TPB constructs to the prediction of intention , whereas habit predicted behaviour directly , and interacted with intentions in predicting behaviour . Habits unexpectedly strengthened the intention-behaviour relation , such that strong intenders were more likely to binge-drink where they also had strong habits . CONCLUSIONS Identity and habit are conceptually discrete and impact differently on binge-drinking . Findings have implication s for habit theory and measurement . Recommendations for student alcohol consumption reduction initiatives are offered OBJECTIVES The aim of this study was to test the effectiveness of a theory of planned behaviour intervention to increase adherence of community mental health professionals to a national suicide prevention guideline . DESIGN Routinely collected audit adherence data from an intervention and control site were collected and analysed using time series analysis to test whether the intervention significantly increased adherence . The effects of a local and national event on adherence were also examined . METHOD A Theory of Planned Behaviour ( TPB ) question naire , developed from interview findings , was administered to the health professionals . Subjective norms were found to be the most significant predictor of intention to adhere to the guideline , and were targeted with an interactive educational intervention . Time series analysis applied to routinely collected audit adherence data was used to test intervention effectiveness . RESULTS The TPB accounted for 58 % of the variance in intention to adhere , with subjective norms the only significant predictor . The intervention did not significantly increase adherence ; however , the national and local events were found to have significantly increased adherence . CONCLUSIONS The TPB was a useful framework for exploring barriers to adherence ; however , this did not translate into an effective intervention . Future research should seek collaboration with local experts , and use this information in combination with the TPB , to develop interventions . Collaborative research with experts in pedagogy may also help to develop more effective interventions , particularly education-based interventions that require adult learning Theory-based intervention programmes to support health-related behaviour change aim to increase health impact and improve underst and ing of mechanisms of behaviour change . However , the science of intervention development remains at an early stage . We present a causal modelling approach to developing complex interventions for evaluation in r and omized trials . In this approach a generic model links behavioural determinants , causally through behaviour , to physiological and biochemical variables , and health outcomes . It is tailored to context , target population , behaviours and health outcomes . The development of a specific causal model based on theory and evidence is illustrated by the ProActive programme , supporting increased physical activity  among individuals at risk of Type 2 diabetes . The model provides a rational guide to appropriate measures , intervention points and intervention techniques , and can be tested quantitatively . Causal modelling is critically compared to other approaches to intervention development and evaluation , and research directions are indicated Background In the ProActive Trial an intensive theory-based intervention program was no more effective than theory-based brief advice in increasing objective ly measured physical activity among adults at risk of Type 2 diabetes . We aim ed to illuminate these findings by assessing whether the intervention program changed cognitions about increasing activity , defined by the Theory of Planned Behaviour , in ways consistent with the theory . Methods N = 365 sedentary participants aged 30–50 years with a parental history of Type 2 diabetes were r and omised to brief advice alone or to brief advice plus the intervention program delivered face-to-face or by telephone . Question naires at baseline , 6 and 12 months assessed cognitions about becoming more physically active . Analysis of covariance was used to test intervention impact . Bootstrapping was used to test multiple mediation of intervention impact . Results At 6 months , combined intervention groups ( face-to-face and telephone ) reported that they found increasing activity more enjoyable ( affective attitude , d = .25 ) , and they perceived more instrumental benefits ( e.g. , improving health ) ( d = .23 ) and more control ( d = .32 ) over increasing activity than participants receiving brief advice alone . Stronger intentions ( d = .50 ) in the intervention groups than the brief advice group at 6 months were partially explained by affective attitude and perceived control . At 12 months , intervention groups perceived more positive instrumental ( d = .21 ) and affective benefits ( d = .29 ) than brief advice participants . The intervention did not change perceived social pressure to increase activity . Conclusion Lack of effect of the intervention program on physical activity over and above brief advice was consistent with limited and mostly small short-term effects on cognitions . Targeting affective benefits ( e.g. , enjoyment , social interaction ) and addressing barriers to physical activity may strengthen intentions , but stronger intentions did not result in more behaviour change . More powerful interventions which induce large changes in TPB cognitions may be needed . Other interventions deserving further evaluation include theory-based brief advice , intensive measurement of physical and psychological factors , and monitoring of physical activity . Future research should consider a wider range of mediators of physical activity change , assess participants ' use of self-regulatory strategies taught in the intervention , and conduct experimental studies or statistical modelling prior to trial evaluation . IS RCT N61323766 OBJECTIVE The theory of planned behaviour ( TPB ) has been criticized for not including interactions between major constructs thought to underlie behaviour . This study investigated the application of the TPB to the prediction of  fruit and vegetable consumption across three prospect i ve cohorts . The primary aim of the study was to investigate whether interactions between major constructs in the theory would increase the ability of the model to predict intention to consume fruit and vegetables ( i.e. , attitude × perceived behavioural control [ PBC ] , subjective norm × PBC , subjective norm × attitude ) and self-reported fruit and vegetable intake ( i.e. , PBC × intention ) . DESIGN Secondary data analysis from three cohorts : One predictive study ( cohort 1 ) and two intervention studies ( cohorts 2 and 3 ) . METHOD Participants completed a TPB measure at baseline and a measure of fruit and vegetable intake at 1 week ( cohort 1 ; n = 90 ) or 1 month ( cohorts 2 and 3 ; n = 296 ) . RESULTS Attitude moderated the impact of PBC on intention . PBC moderated the impact of intention on behaviour at 1 week but not 1 month . CONCLUSION The variance accounted for by the interactions was small . However , the presence of interactions between constructs within the TPB demonstrates a need to consider interactions between variables within the TPB in both theoretical and applied research using the model
Several studies of good quality demonstrated changes in lifestyle habits arising from the provision of genetic interventions .
The most promising lifestyle changes were changes in nutrition .
Conclusions : It is possible to facilitate behaviour change using genetic testing as the catalyst .
Background : Study ing the impact of  genetic testing interventions on lifestyle behaviour change  has been a priority area of research in recent years .
Substantial heterogeneity exists in the results and conclusions of this literature , which has yet to be explained using vali date d behaviour change theory and an assessment of the quality of genetic interventions .
The theory of planned behaviour ( TPB ) helps to explain key contributors to behaviour change .
It has been hypothesized that personalization could be added to this theory to help predict changes in health behaviours .
Purpose : This systematic review provides a detailed , comprehensive identification , assessment , and summary of primary research articles pertaining to  lifestyle behaviour change  ( nutrition , physical activity , sleep , and smoking ) result ing from  genetic testing interventions .
The present review further aims to provide in-depth analyses of studies conducted to date within the context of the TPB and the quality of genetic interventions provided to participants while aim ing to determine whether or not genetic testing facilitates changes in lifestyle habits .
This review is timely in light of a recently published “ call-to-action ” paper , highlighting the need to incorporate the TPB into personalized healthcare behaviour change research .