Wendy Hardeman

The Behavior Change Technique Taxonomy (v1) of 93 Hierarchically Clustered Techniques: Building an International Consensus for the Reporting of Behavior Change Interventions.

BackgroundCONSORT guidelines call for precise reporting of behavior change interventions: we need rigorous methods of characterizing active content of interventions with precision and specificity.ObjectivesThe objective of this study is to develop an extensive, consensually agreed hierarchically structured taxonomy of techniques [behavior change techniques (BCTs)] used in behavior change interventions.MethodsIn a Delphi-type exercise, 14 experts rated labels and definitions of 124 BCTs from six published classification systems. Another 18 experts grouped BCTs according to similarity of active ingredients in an open-sort task. Inter-rater agreement amongst six researchers coding 85 intervention descriptions by BCTs was assessed.ResultsThis resulted in 93 BCTs clustered into 16 groups. Of the 26 BCTs occurring at least five times, 23 had adjusted kappas of 0.60 or above.Conclusions“BCT taxonomy v1,” an extensive taxonomy of 93 consensually agreed, distinct BCTs, offers a step change as a method for specifying interventions, but we anticipate further development and evaluation based on international, interdisciplinary consensus.

Process evaluation of complex interventions: Medical Research Council guidance

Process evaluation is an essential part of designing and testing complex interventions. New MRC guidance provides a framework for conducting and reporting process evaluation studies

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

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

Family involvement in weight control, weight maintenance and weight-loss interventions: a systematic review of randomised trials

OBJECTIVE: To conduct a descriptive systematic review into the nature and effectiveness of family involvement in weight control, weight maintenance and weight-loss interventions.METHOD: We searched Medline and Psyclit for English language papers describing randomised trials with at least 1-y follow-up that evaluated interventions incorporating a family-based component. Studies involving people with eating disorders, learning disabilities and undernutrition or malnutrition were excluded. Data were extracted on characteristics of the participants, study design, target behaviours, nature of the intervention and study outcomes. A taxonomy was developed and used to classify family involvement in behaviour change interventions. Interventions were also classified according to an existing taxonomy that characterised the behaviour change techniques employed.RESULTS: A total of 21 papers describing 16 intervention studies were identified. Studies were small (mean sample size: 52), heterogeneous, poorly described but with few losses to follow-up (median 15%). The majority were North American and aimed at weight loss. Few studies described a theoretical underpinning to the behaviour change techniques employed. There was a suggestion that spouse involvement increased effectiveness but that adolescents achieved greater weight loss when treated alone. In studies including children, beneficial effects were seen when greater numbers of behaviour change techniques were taught to both parents and children.CONCLUSION: Relatively few intervention studies exist in this important area, particularly studies targeting adolescents, and they highlight continued uncertainty about how best to involve family members. The studies provide limited support for the involvement of spouses. They suggest that parental involvement is associated with weight loss in children, and that use of a greater range of behaviour change techniques improves weight outcomes for both parents and children. The development of future interventions and assessment of factors influencing effectiveness may be improved by paying careful attention to which family members are targeted and how they are involved in the intervention in terms of setting goals for behaviour change, providing support and training in behaviour change techniques.

Interventions to prevent weight gain: a systematic review of psychological models and behaviour change methods.

OBJECTIVE: To identify and review published interventions aimed at the prevention of weight gain.DESIGN: A systematic review of published interventions aimed at the prevention of weight gain.METHODS: Search strategies—we searched eight databases, manually checked reference lists and contacted authors. Inclusion and exclusion criteria—studies of any design, in which participants were selected regardless of weight or age, were included. Interventions targeting a specific subgroup, multifactorial interventions, interventions aimed at weight loss, and those with an ambiguous aim were excluded. Data extraction—data were extracted on behaviours targeted for change, psychological model, behaviour change methods and modes of delivery, methodological quality, characteristics of participants, and outcomes related to body weight and self-reported diet and physical activity. Classification and validation—a taxonomy of behaviour change programmes was developed and used for classification of underlying model, behaviour change methods, and modes of delivery. The data extraction and subsequent classification were independently validated.RESULTS: Eleven publications were included, describing five distinct interventions in schools and four in the wider community. Where diet and physical activity were described, positive effects were usually obtained, but all were measured by self-report. Effects on weight were mixed but follow-up was generally short. Smaller effects on weight gain were found among low-income participants, students and smokers. Many participants in the community-based studies were overweight or obese. Study dropout was higher among thinner and lower-income subjects.CONCLUSION: Interventions to prevent weight gain exhibited various degrees of effectiveness. Definite statements about the elements of the interventions that were associated with increased effect size cannot be made as only one of the five studies that involved an RCT design reported a significant effect on weight. This intervention involved a correspondence programme and a mix of behaviour change methods including goal setting, self-monitoring and contingencies. Future interventions might be more effective if they were explicitly based on methods of behaviour change that have been shown to work in other contexts. Effective interventions would be more easily replicated if they were explicitly described. Effectiveness might be more precisely demonstrated if more objective measures of physical activity and diet were used, and if the follow-up was over a longer period.

Process evaluation in complex public health intervention studies: the need for guidance

Public health interventions aim to improve the health of populations or at-risk subgroups. Problems targeted by such interventions, such as diet and smoking, involve complex multifactorial aetiology. Interventions will often aim to address more than one cause simultaneously, targeting factors at multiple levels (eg, individual, interpersonal, organisational), and comprising several components which interact to affect more than one outcome.1 They will often be delivered in systems which respond in unpredictable ways to the new intervention.2 Recognition is growing that evaluations need to understand this complexity if they are to inform future intervention development, or efforts to apply the same intervention in another setting or population.1 Achieving this will require evaluators to move beyond a ‘does it work?’ focus, towards combining outcomes and process evaluation. There is no such thing as a typical process evaluation, with the term applied to studies which range from a few simple quantitative items on satisfaction, to complex mixed-method studies exploring issues such as the process of implementation, or contextual influences on implementation and outcomes. As recognised within MRC guidance for evaluating complex interventions, process evaluation may be used to ‘assess fidelity and quality of implementation , clarify causal mechanisms and identify contextual factors associated with variation in outcomes’.1 This paper briefly discusses each of these core aims for process evaluation, before describing current Medical Research Council (MRC) Population Health Sciences Research Network (PHSRN) funded work to develop guidance for process evaluations of complex public health interventions. ### Intervention implementation An important role for process evaluations is to examine the quantity and quality of what was actually implemented in practice, and why. This may inform implementation of similar interventions elsewhere, and facilitate interpretation of intervention outcomes. While notions of standardisation are central to implementation assessment, the nature of …

Fidelity of delivery of a physical activity intervention: predictors and consequences.

Assessing fidelity of behavioural interventions is important, but demanding and rarely done. This study assessed adherence to behaviour change techniques used in an intervention to increase physical activity among sedentary adults ( ProActive ; N = 365). Transcripts of 108 sessions with a sub-sample of 27 participants were assessed. An independent assessor coded adherence of four ‘facilitators’ who delivered the intervention to 208 protocol-specified facilitator behaviours (e.g. ‘elicit perceived advantages of becoming more active’) in four key sessions. Four raters classified the 208 behaviours under 14 techniques (e.g., goal setting, use of rewards) to enable calculation of adherence to techniques. Observed adherence to techniques across participants was modest (median 44%, IQR 35–62%), and lower than that reported by facilitators. Adherence differed between facilitators (range: 26–63%) and decreased across the four sessions (mean drop 9% per session, 95% confidence interval 7–11%). In this small sample facilitator adherence was unrelated to (change in) participants’ physical activity or its cognitive predictors: Attitudes, subjective norm, perceived behavioural control and intention. Future research should investigate causal pathways between fidelity indicators and outcomes in larger samples and develop and test less intensive measures of fidelity.

The ProActive trial protocol – a randomised controlled trial of the efficacy of a family-based, domiciliary intervention programme to increase physical activity among individuals at high risk of diabetes [ISRCTN61323766]

BackgroundIncreasing prevalence of obesity and disorders associated with sedentary living constitute a major global public health problem. While previous evaluations of interventions to increase physical activity have involved communities or individuals with established disease, less attention has been given to interventions for individuals at risk of disease.Methods/designProActiveaims to evaluate the efficacy of a theoretical, evidence- and family-based intervention programme to increase physical activity in a sedentary population, defined as being at-risk through having a parental family history of diabetes. Primary care diabetes or family history registers were used to recruit 365 individuals aged 30–50 years, screened for activity level. Participants were assigned by central randomisation to three intervention programmes: brief written advice (comparison group), or a psychologically based behavioural change programme, delivered either by telephone (distance group) or face-to-face in the family home over one year. The protocol-driven intervention programme is delivered by trained facilitators, and aims to support increases in physical activity through the introduction and facilitation of a range of self-regulatory skills (e.g. goal setting). The primary outcome is daytime energy expenditure and its ratio to resting energy expenditure, measured at baseline and one year using individually calibrated heart rate monitoring. Secondary measures include self-report of individual and family activity, psychological mediators of behaviour change, physiological and biochemical correlates, acceptability, and costs, measured at baseline, six months and one year. The primary intention to treat analysis will compare groups at one-year post randomisation. Estimation of the impact on diabetes incidence will be modelled using data from a parallel ten-year cohort study using similar measures.DiscussionProActiveis the first efficacy trial of an intervention programme to promote physical activity in a defined high-risk group accessible through primary care. The intervention programme is based on psychological theory and evidence; it introduces and facilitates the use of self-regulatory skills to support behaviour change and maintenance. The trial addresses a range of methodological weaknesses in the field by careful specification and quality assurance of the intervention programme, precise characterisation of participants, year-long follow-up and objective measurement of physical activity. Due to report in 2005, ProActivewill provide estimates of the extent to which this approach could assist at-risk groups who could benefit from changes in behaviours affecting health, and inform future pragmatic trials.

Investigating theoretical explanations for behaviour change: The case study of ProActive

Developing more effective behavioural interventions requires an understanding 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.

An explanatory randomised controlled trial of a nurse-led, consultation-based intervention to support patients with adherence to taking glucose lowering medication for type 2 diabetes

BackgroundFailure to take medication reduces the effectiveness of treatment leading to increased morbidity and mortality. We evaluated the efficacy of a consultation-based intervention to support objectively-assessed adherence to oral glucose lowering medication (OGLM) compared to usual care among people with type 2 diabetes.MethodsThis was a parallel group randomised trial in adult patients with type 2 diabetes and HbA1c≥7.5% (58 mmol/mol), prescribed at least one OGLM. Participants were allocated to a clinic nurse delivered, innovative consultation-based intervention to strengthen patient motivation to take OGLM regularly and support medicine taking through action-plans, or to usual care. The primary outcome was the percentage of days on which the prescribed dose of medication was taken, measured objectively over 12 weeks with an electronic medication-monitoring device (TrackCap, Aardex, Switzerland). The primary analysis was intention-to-treat.Results211 patients were randomised between July 1, 2006 and November 30, 2008 in 13 British general practices (primary care clinics). Primary outcome data were available for 194 participants (91.9%). Mean (sd) percentage of adherent days was 77.4% (26.3) in the intervention group and 69.0% (30.8) in standard care (mean difference between groups 8.4%, 95% confidence interval 0.2% to 16.7%, p = 0.044). There was no significant adverse impact on functional status or treatment satisfaction.ConclusionsThis well-specified, theory based intervention delivered in a single session of 30 min in primary care increased objectively measured medication adherence, with no adverse effect on treatment satisfaction. These findings justify a definitive trial of this approach to improving medication adherence over a longer period of time, with clinical and cost-effectiveness outcomes to inform clinical practice.Trial registrationCurrent Controlled Trials ISRCTN30522359