Identification of behaviour change techniques and engagement strategies to design a smartphone app to reduce alcohol consumption using a formal consensus method

Background: Digital interventions to reduce excessive alcohol consumption have the potential to have a broader reach and be more cost-effective than traditional brief interventions. However, there is not yet a strong evidence base on their ability to engage users or on their effectiveness. Objective: This study aimed to identify the behaviour change techniques (BCTs) and engagement strategies most worthy of further study by inclusion in a smartphone application (app) to reduce alcohol consumption, using formal expert consensus methods. Methods: The first phase of the study consisted of a Delphi exercise with three rounds. It was conducted with seven international experts in the field of alcohol and/or behaviour change. In the first round, experts identified BCTs most likely to be effective at reducing alcohol consumption and strategies most likely to engage users with an app; these were rated in the second round; and those rated as effective by at least four out of seven participants were ranked in the third round. The rankings were analysed using Kendall’s W coefficient of concordance, which indicates consensus between participants. The second phase consisted of a new, independent group of experts (n=43) ranking the BCTs that were identified in the first phase. The correlation between the rankings of the two groups was assessed using Spearman’s rank correlation coefficient. Results: Twelve BCTs were identified as likely to be effective. There was moderate agreement among the experts over their ranking (W=.465, χ2(11)=35.77, P<.001) and the BCTs receiving the highest mean rankings were self-monitoring, goal-setting, action planning, and feedback in relation to goals. There was a significant correlation between the ranking of the BCTs by the group of experts who identified them and a second independent group of experts (Spearman’s rho=.690, P=.01). Seventeen responses were generated for strategies likely to engage users. There was moderate agreement among experts on the ranking of these engagement strategies (W=.563, χ2(15)=59.16, P<.001) and those with the highest mean rankings were ease of use, design – aesthetic, feedback, function, design – ability to change design to suit own preferences, tailored information, and unique smartphone features. Conclusions: The BCTs with greatest potential to include in a smartphone app to reduce alcohol consumption were judged by experts to be self-monitoring, goal-setting, action planning, and feedback in relation to goals. The strategies most likely to engage users were ease of use, design, tailoring of design and information, and unique smartphone features

Double minimum in the surface stabilized ferroelectric liquid crystal switching response

A double minimum has recently been observed in the time–voltage switching response for a smectic C* liquid crystal layer in the surface stabilized geometry (“Ferroelectric Liquid Crystal Device,” K. P. Lymer and J. C. Jones, U.K. Patent No. GB2338797, 17th June 1999). Liquid crystal continuum theory is used to demonstrate that this unusual switching behavior arises if the equilibrium orientation of the molecular director rotates around the smectic cone as a function of distance through one half of the layer only. The double minimum is shown to evolve for large differences between the ε2 and ε1 components of the smectic C biaxial permittivity tensor

Correlating peer and tutor assessment on a low-stakes engineering assignment

Peer assessment has been a subject of great debate in recent years. The way students perceive assessment and what motivates them when assessing may differ significantly from the tutor. This paper discusses a study designed to correlate students marking with the marks awarded by their tutors when peer assessing one another from in-class oral presentations. A new and alternative approach to correlate results is presented, which is based on the normalisation of the quantitative judgements based on determined criteria. The methodology was blind and holistic, as described in previous works: some guidelines were provided to the students on what is considered acceptable without getting into detail (holistic marking), and peer-assessment marks were made confidential (blind approach). It was observed that students have a tendency to overrate fellow students - especially where lower marks might be awarded. There is, however, direct agreement with the tutors marking in terms of qualitative judgements, which is highlighted by the presented correlation method used to adjust students marks. The presented methodology to correlate marks between the students and tutor showed to be a promising one. After processing the data with this simple and straightforward algorithm, peer and tutor assessment practically showed a perfect match

Electric field induced reversible spreading of droplets into films on lubricant impregnated surfaces

Electric fields can be used to force a droplet to wet a solid surface using an applied voltage. However, significant hysteresis usually occurs associated with pinning forces at the contact line. Here, we report the forced spreading and subsequent retraction of droplets into liquid films in air on lubricant impregnated surfaces (also known as slippery liquid infused porous surfaces) where the contact line is completely mobile. We first confirm that we achieve a complete removal of hysteresis for the electrowetting of droplets above the saturation voltage. We then show that contact angle hysteresis can be reduced to less than 4° whilst retaining the ability to fully spread a droplet into a liquid film using an interface localized from liquid dielectrophoresis (dielectrowetting). In both cases, we find that the cosine of the contact angle has a quadratic dependence on applied voltage, consistent with previous theoretical expectations. Thus, our work demonstrates that fully reversible spreading encompassing a wide range of partial wetting droplet states and a film state can be achieved in air in a controllable manner with very low levels of hysteresis

Estimating effectiveness of components of a smartphone app – Drink Less – to reduce excessive alcohol consumption

Background: Smartphone apps have the potential to help drinkers reduce hazardous and harmful alcohol consumption. However, there have been few evaluations of the effectiveness of these apps and none to our knowledge that estimates the effects of individual intervention components. This study aimed to evaluate the effectiveness of intervention components of an alcohol reduction app, Drink Less. Materials and Methods: Drink Less is a freely available app to any individual in the UK making an attempt to reduce their drinking. The app was structured around goal setting with information on the UK drinking guidelines, units and alcohol-related harms. The app offered access to five additional intervention modules – Normative Feedback, Cognitive Bias Re-training, Self-monitoring and Feedback, Action Planning and Identity Change – to help them achieve their goal. Excessive drinkers (AUDIT >=8) who were aged 18+ were orthogonally randomised to receive ‘enhanced’ or ‘minimal’ versions of each of the five modules (to a total of 25 experimental conditions). The primary outcome measure was change in past week consumption at one-month follow-up. Secondary measures were change in AUDIT score, usage data and usability ratings. A factorial between-subjects ANOVA assessed main and interactive effects of the app modules using an intention-to-treat analysis. Results: Of 672 study participants, 27% responded to follow-up. At baseline, the mean past week consumption was 39.9 units (SD=27.34) and mean AUDIT score was 19.1 (SD=6.56). There were no significant main effects of the intervention modules on either measure. There were two-way interactions between enhanced Self-monitoring and Feedback and Action Planning on AUDIT score (F=5.818, p=0.016) and between enhanced Normative Feedback and Cognitive Bias Re-training on past week consumption (F=4.676, p=0.031). Enhanced Self-monitoring and Feedback was used more often and rated more positively for helpfulness, satisfaction and recommendation than the minimal version. Conclusions: Individual enhanced modules were not more effective compared with their minimal condition. The combinations of Self-monitoring and Feedback with Action Planning, and Normative Feedback with Cognitive Bias Re-training resulted in significant reductions in alcohol-related outcomes when both modules were enhanced. Users rated the Self-monitoring and Feedback module significantly more positively when it was enhanced

Dynamic response of a thin sessile drop of conductive liquid to an abruptly applied or removed electric field

We consider, both theoretically and experimentally, a thin sessile drop of conductive liquid that rests on the lower plate of a parallel-plate capacitor. We derive analytical expressions for both the initial deformation and the relaxation dynamics of the drop as the electric field is either abruptly applied or abruptly removed, as functions of the geometrical, electrical, and material parameters, and investigate the ranges of validity of these expressions by comparison with full numerical simulations. These expressions provide a reasonable description of the experimentally measured dynamic response of a drop of conductive ionic liquid 1-butyl-3-methyl imidazolium tetrafluoroborate

Baby-Led Weaning: The Evidence to Date

Purpose of ReviewInfants are traditionally introduced to solid foods using spoon-feeding of specially prepared infant foods.Recent FindingsHowever, over the last 10–15 years, an alternative approach termed ‘baby-led weaning’ has grown in popularity. This approach involves allowing infants to self-feed family foods, encouraging the infant to set the pace and intake of the meal. Proponents of the approach believe it promotes healthy eating behaviour and weight gain trajectories, and evidence is starting to build surrounding the method. This review brings together all empirical evidence to date examining behaviours associated with the approach, its outcomes and confounding factors.SummaryOverall, although there is limited evidence suggesting that a baby-led approach may encourage positive outcomes, limitations of the data leave these conclusions weak. Further research is needed, particularly to explore pathways to impact and understand the approach in different contexts and populations

Connective tissue disease related interstitial lung diseases and idiopathic pulmonary fibrosis: provisional core sets of domains and instruments for use in clinical trials

Rationale Clinical trial design in interstitial lung diseases (ILDs) has been hampered by lack of consensus on appropriate outcome measures for reliably assessing treatment response. In the setting of connective tissue diseases (CTDs), some measures of ILD disease activity and severity may be confounded by non-pulmonary comorbidities. Methods The Connective Tissue Disease associated Interstitial Lung Disease (CTD-ILD) working group of Outcome Measures in Rheumatology—a non-profit international organisation dedicated to consensus methodology in identification of outcome measures—conducted a series of investigations which included a Delphi process including >248 ILD medical experts as well as patient focus groups culminating in a nominal group panel of ILD experts and patients. The goal was to define and develop a consensus on the status of outcome measure candidates for use in randomised controlled trials in CTD-ILD and idiopathic pulmonary fibrosis (IPF). Results A core set comprising specific measures in the domains of lung physiology, lung imaging, survival, dyspnoea, cough and health-related quality of life is proposed as appropriate for consideration for use in a hypothetical 1-year multicentre clinical trial for either CTD-ILD or IPF. As many widely used instruments were found to lack full validation, an agenda for future research is proposed. Conclusion Identification of consensus preliminary domains and instruments to measure them was attained and is a major advance anticipated to facilitate multicentre RCTs in the field

A meta-analytic review of stand-alone interventions to improve body image

Objective Numerous stand-alone interventions to improve body image have been developed. The present review used meta-analysis to estimate the effectiveness of such interventions, and to identify the specific change techniques that lead to improvement in body image. Methods The inclusion criteria were that (a) the intervention was stand-alone (i.e., solely focused on improving body image), (b) a control group was used, (c) participants were randomly assigned to conditions, and (d) at least one pretest and one posttest measure of body image was taken. Effect sizes were meta-analysed and moderator analyses were conducted. A taxonomy of 48 change techniques used in interventions targeted at body image was developed; all interventions were coded using this taxonomy. Results The literature search identified 62 tests of interventions (N = 3,846). Interventions produced a small-to-medium improvement in body image (d+ = 0.38), a small-to-medium reduction in beauty ideal internalisation (d+ = -0.37), and a large reduction in social comparison tendencies (d+ = -0.72). However, the effect size for body image was inflated by bias both within and across studies, and was reliable but of small magnitude once corrections for bias were applied. Effect sizes for the other outcomes were no longer reliable once corrections for bias were applied. Several features of the sample, intervention, and methodology moderated intervention effects. Twelve change techniques were associated with improvements in body image, and three techniques were contra-indicated. Conclusions The findings show that interventions engender only small improvements in body image, and underline the need for large-scale, high-quality trials in this area. The review identifies effective techniques that could be deployed in future interventions