Meaningful change definitions: sample size planning for experimental intervention research.

Experimental tests of interventions need to have sufficient sample size to constitute a robust test of the intervention's effectiveness with reasonable precision and power. To estimate the required sample size adequately, researchers are required to specify an effect size. But what effect size should be used to plan the required sample size? Various inroads into selecting the a priori effect size have been suggested in the literature-including using conventions, prior research, and theoretical or practical importance. In this paper, we first discuss problems with some of the proposed methods of selecting the effect size for study planning. We then lay out a method for intervention researchers that provides a way out of many of these problems. The proposed method requires setting a meaningful change definition, it is specifically suited for applied researchers interested in planning tests of intervention effectiveness. We provide a hands-on walk through of the method and provide easy-to-use R functions to implement it.

Sexual Arousal and Implicit and Explicit Determinants of Condom Use Intentions.

Being sexually aroused may be an important risk factor contributing to sexual decision making. Dual-process cognitive models, such as the reflective-impulsive model of Strack and Deutsch (2004), could be used to explain the effect of sexual arousal on intentions to use a condom. In this study, we investigated whether explicit and implicit attitudes toward condom use can predict intentions to use a condom when participants are sexually aroused and not aroused. In a within-subjects experimental design, male participants (N = 27) watched both a neutral and an erotic movie clip in counterbalanced order. After each clip, participants completed a questionnaire assessing their intentions to use a condom and explicit condom attitudes, followed by a wanting Implicit Association Test (IAT; Greenwald et al., 2003) and a liking IAT to assess their implicit attitudes to unsafe sex. In concordance with the reflective-impulsive model, we found that when participants were not sexually aroused, their intentions to use a condom were solely predicted by their explicit attitudes. However, when they were sexually aroused, intentions to use a condom were predicted by both explicit and implicit attitudes toward condom use.

Ignoring theory and misinterpreting evidence: the false belief in fear appeals.

Use of fear appeals assumes that when people are emotionally confronted with the negative effects of their behaviour they will change that behaviour. That reasoning is simple and intuitive, but only true under specific, rare circumstances. Risk perception theories predict that if people will experience a threat, they want to counter that threat. However, how they do so is determined by their coping efficacy level: if efficacy is high, they may change their behaviour in the suggested direction; if efficacy is low, they react defensively. Research on fear appeals should be methodologically sound, comparing a threatening to a non-threatening intervention under high and low efficacy levels, random assignment and measuring behaviour as outcome. We critically review extant empirical evidence and conclude that it does not support positive effects of fear appeals. Nonetheless, their use persists and is even promoted by health psychology researchers, causing scientific insights to be ignored or misinterpreted.

The Psychological Effects of Strength Exercises in People who are Overweight or Obese: A Systematic Review.

BACKGROUND: Overweightness and obesity represent a high burden on well-being and society. Strength training has positive effects on body composition and metabolic health for people who are overweight or obese. The evidence for psychological effects of strength exercises is unclear. OBJECTIVE: The aim of this study was to assess the psychological effects of strength exercises for people who are overweight or obese. METHODS: Relevant literature was identified by use of the PubMed and PsycINFO databases. For each study, effect sizes and corresponding variance estimates were extracted or calculated for the main effects of strength exercises on psychological outcomes. RESULTS: Seventeen studies were included. There was almost no overlap among the various measures of psychological constructs. The constructs were ordered into eight broad categories. Meta-analytical techniques revealed substantial heterogeneity in effect sizes, and combined with the low number of effect size estimates for each outcome measure, this precluded meta-analysis. Organization of the data showed that the evidence base so far does not show convincing effects of strength training on psychological outcome measures. Some weak effects emerged on self-efficacy, self-esteem, inhibition, and psychological disorders (e.g., anxiety and depression). No additional or comparable effects to other interventions were found for mood, outcome expectations, quality of life, and stress. DISCUSSION: The main finding of this review is that despite a strong theoretical basis for expecting positive effects of strength training on psychological outcomes, the literature shows a large gap in this area. The existing research does not show a clear picture: some positive results might exist, but there is a strong need to accumulate more evidence before drawing conclusions.

Nocturnal incontinence in children with fetal alcohol spectrum disorders (FASD) in a South African cohort.

INTRODUCTION: Fetal alcohol spectrum disorders (FASD) are one of the leading preventable causes of intellectual disabilities (ID). Not much is known about the topic of pediatric incontinence related to FASD, for example nocturnal enuresis (NE), daytime urinary incontinence (DUI), and fecal incontinence (FI). So far, incontinence problems have been examined among children with other specific syndromes. OBJECTIVE: The aim of the present study is to investigate the possible presence of incontinence among children with FASD in a South African cohort. STUDY DESIGN: The South African version of the combined questionnaire including the "Parental Questionnaire: Enuresis/Urinary Incontinence" and "Encopresis Questionnaire - Screening Version"; and lower urinary tract symptoms (LUTS) were assessed by the "International-Consultation-on-Incontinence-Questionnaire - Pediatric Lower Urinary Tract Symptom" (ICIQ-CLUTS) among 99 interviewees (e.g. mothers, grandparents) of children with FASD. Moreover, scores on the "Griffiths Mental Development Scales - Extended Revised" (GMDS-ER) were obtained of all included children for further statistical analysis. RESULTS: The overall incontinence rate was 20% (n = 20), in children diagnosed within the FASD spectrum (fetal alcohol syndrome or FAS n = 17, partial fetal alcohol syndrome or pFAS, n = 1, alcohol related neurodevelopmental disorder or ARND n = 2). NE affected 16% (n = 16) of children with a FASD (FAS n = 13, pFAS n = 1, and ARND n = 2). DUI was reported in one child (FAS), and FI in 4% (n = 4) of children (again, only FAS). No indication of lower urinary tract symptoms (LUTS) in the clinical range was reported (sample mean score = 5.17). Based on the GMDS-ER, 88% of the children scored lower than 10th percentile. DISCUSSION: This is a first study to examine the problems of incontinence among children diagnosed within the spectrum of FASD. The rates for children with a FASD are lower than the rates for many children with special needs, but much higher than for typically developing children. Children with a FASD are mainly affected by NE. CONCLUSION: The problem of incontinence among children with a FASD in South Africa needs to be assessed and considered for clinical management. Future research is necessary to examine problems of incontinence in relation to cognitive and behavioral functioning among children with a FASD, as well as identifying possible causes.

Worldwide Prevalence of Fetal Alcohol Spectrum Disorders: A Systematic Literature Review Including Meta-Analysis.

BACKGROUND: Although fetal alcohol spectrum disorders (FASD) affect communities worldwide, little is known about its prevalence. The objective of this study was to provide an overview of the global FASD prevalence. METHODS: We performed a search in multiple electronic bibliographic databases up to August 2015, supplemented with the ascendancy and descendancy approach. Studies were considered when published in English, included human participants, and reported empirical data on prevalence or incidence estimates of FASD. Raw prevalence estimates were transformed using the Freeman-Tukey double arcsine transformation so that the data followed an approximately normal distribution. Once the pooled prevalence estimates, 95% confidence intervals and prediction intervals were calculated based on multiple meta-analyses with transformed proportions using random effects models, these estimates were transformed back to regular prevalence rates. Heterogeneity was tested using Cochran's Q and described using the I(2) statistic. RESULTS: Among studies that estimated prevalence in general population samples, considerable differences in prevalence rates between countries were found and therefore separate meta-analyses for country were conducted. Particularly high-prevalence rates were observed in South Africa for fetal alcohol syndrome (55.42 per 1,000), for alcohol-related neurodevelopmental disorder (20.25 per 1,000), and FASD (113.22 per 1,000), For partial fetal alcohol syndrome high rates were found in Croatia (43.01 per 1,000), Italy (36.89 per 1,000), and South Africa (28.29 per 1,000). In the case of alcohol-related birth defects, a prevalence of 10.82 per 1,000 was found in Australia. However, studies into FASD exhibited substantial heterogeneity, which could only partly be explained by moderators, most notably geography and descent, in meta-regressions. In addition, the moderators were confounded, making conclusions as to each moderator's relevance tentative at best. CONCLUSIONS: The worldwide pooled prevalence estimates are higher than assumed so far, but this was largely explained by geography and descent. Furthermore, prevalence studies varied considerably in terms of used methodology and methodological quality. The pooled estimates must therefore be interpreted with caution and for future research it is highly recommended to report methodology in a more comprehensive way. Finally, clear guidelines on assessing FASD prevalence are urgently needed, and a first step toward these guidelines is presented.

A taxonomy of behaviour change methods: an Intervention Mapping approach.

In this paper, we introduce the Intervention Mapping (IM) taxonomy of behaviour change methods and its potential to be developed into a coding taxonomy. That is, although IM and its taxonomy of behaviour change methods are not in fact new, because IM was originally developed as a tool for intervention development, this potential was not immediately apparent. Second, in explaining the IM taxonomy and defining the relevant constructs, we call attention to the existence of parameters for effectiveness of methods, and explicate the related distinction between theory-based methods and practical applications and the probability that poor translation of methods may lead to erroneous conclusions as to method-effectiveness. Third, we recommend a minimal set of intervention characteristics that may be reported when intervention descriptions and evaluations are published. Specifying these characteristics can greatly enhance the quality of our meta-analyses and other literature syntheses. In conclusion, the dynamics of behaviour change are such that any taxonomy of methods of behaviour change needs to acknowledge the importance of, and provide instruments for dealing with, three conditions for effectiveness for behaviour change methods. For a behaviour change method to be effective: (1) it must target a determinant that predicts behaviour; (2) it must be able to change that determinant; (3) it must be translated into a practical application in a way that preserves the parameters for effectiveness and fits with the target population, culture, and context. Thus, taxonomies of methods of behaviour change must distinguish the specific determinants that are targeted, practical, specific applications, and the theory-based methods they embody. In addition, taxonomies should acknowledge that the lists of behaviour change methods will be used by, and should be used by, intervention developers. Ideally, the taxonomy should be readily usable for this goal; but alternatively, it should be clear how the information in the taxonomy can be used in practice. The IM taxonomy satisfies these requirements, and it would be beneficial if other taxonomies would be extended to also meet these needs.

Towards a common terminology: a simplified framework of interventions to promote and integrate evidence into health practices, systems, and policies.

BACKGROUND: A wide range of diverse and inconsistent terminology exists in the field of knowledge translation. This limits the conduct of evidence syntheses, impedes communication and collaboration, and undermines knowledge translation of research findings in diverse settings. Improving uniformity of terminology could help address these challenges. In 2012, we convened an international working group to explore the idea of developing a common terminology and an overarching framework for knowledge translation interventions. FINDINGS: Methods included identifying and summarizing existing frameworks, mapping together a subset of those frameworks, and convening a multi-disciplinary group to begin working toward consensus. The group considered four potential approaches to creating a simplified framework: melding existing taxonomies, creating a framework of intervention mechanisms rather than intervention strategies, using a consensus process to expand one of the existing models/frameworks used by the group, or developing a new consensus framework. CONCLUSIONS: The work group elected to draft a new, simplified consensus framework of interventions to promote and integrate evidence into health practices, systems and policies. The framework will include four key components: strategies and techniques (active ingredients), how they function (causal mechanisms), how they are delivered (mode of delivery), and what they aim to change (intended targets). The draft framework needs to be further developed by feedback and consultation with the research community and tested for usefulness through application and evaluation.

Sixty years of fear appeal research: current state of the evidence.

Fear arousal is widely used in persuasive campaigns and behavioral change interventions. Yet, experimental evidence argues against the use of threatening health information. The authors reviewed the current state of empirical evidence on the effectiveness of fear appeals. Following a brief overview of the use of fear arousal in health education practice and the structure of effective fear appeals according to two main theoretical frameworks-protection motivation theory and the extended parallel process model-the findings of six meta-analytic studies in the effectiveness of fear appeals are summarized. It is concluded that coping information aimed at increasing perceptions of response effectiveness and especially self-efficacy is more important in promoting protective action than presenting threatening health information aimed at increasing risk perceptions and fear arousal. Alternative behavior change methods than fear appeals should be considered.

Threatening communication: a qualitative study of fear appeal effectiveness beliefs among intervention developers, policymakers, politicians, scientists, and advertising professionals.

Threatening communication is a widely applied method in behavior change interventions, which at the same time has been heavily criticized in the psychological literature. The current paper describes a study of the reasons for this persistent wide application of threatening communication. We conducted qualitative interviews with 33 key actors in behavior change intervention development in The Netherlands. Specifically, we interviewed intervention developers, policymakers, politicians, scientists, and advertising professionals. The interviews were transcribed and subsequently coded using NVivo. We found that participants most closely involved with the actual intervention development were generally convinced that threatening information was to be prevented, but often did not understand the exact processes involved. They were often under the impression that rather than a potent efficacy enhancing element, a behavioral suggestion would suffice to prevent threatening communication from backfiring. As participants were further removed from the actual intervention development, they generally tended to be more in favor of threatening communication. The main reasons for use of threatening information were to attract attention or prompt self-reflection through confrontation, because target population members were assumed to like threatening information and respond rationally to increased risk perceptions by changing their behavior, or simply because no alternatives were available. In addition, intervention developers frequently had to deal with supervisors or funders who preferred threatening communication. Thus, when communicating with practitioners, it seems fruitful to provide them with a toolbox of evidence-based behavior change methods that promote adaptive, rather than maladaptive, behavior; to promote basing interventions on the most relevant behavioral determinants as identified by determinant analyses; and to equip intervention developers with the tools to persuade other key stakeholders that fear is a bad counselor.

[Graphic images on cigarette packages not effective]. / Enge plaatjes op sigarettenpakjes niet zinvol.

The Dutch Government intends to make graphic images on cigarette packages mandatory. However, contrary to other policy measures to reduce smoking, health warnings do not work. There is no acceptable evidence in favour of graphic images and behaviour change theories suggest methods of change that improve skills, self-efficacy and social support. Thus, theory- and evidence-based policy should focus on prohibiting the tobacco industry from glamourizing packaging and make health communications on packages mandatory. As to the type of communications to be used, theory and evidence suggest that warning of the negative consequences of smoking is not an effective approach. Rather, targeting the most important determinants of the initiation of smoking and its successful cessation - such as skills, self-efficacy and subjective norm - along with the most effective behaviour change methods appears to be the most expedient strategy.

Reactions to threatening health messages.

BACKGROUND: Threatening health messages that focus on severity are popular, but frequently have no effect or even a counterproductive effect on behavior change. This paradox (i.e. wide application despite low effectiveness) may be partly explained by the intuitive appeal of threatening communication: it may be hard to predict the defensive reactions occurring in response to fear appeals. We examine this hypothesis by using two studies by Brown and colleagues, which provide evidence that threatening health messages in the form of distressing imagery in anti-smoking and anti-alcohol campaigns cause defensive reactions. METHODS: We simulated both Brown et al. experiments, asking participants to estimate the reactions of the original study subjects to the threatening health information (n = 93). Afterwards, we presented the actual original study outcomes. One week later, we assessed whether this knowledge of the actual study outcomes helped participants to more successfully estimate the effectiveness of the threatening health information (n = 72). RESULTS: Results showed that participants were initially convinced of the effectiveness of threatening health messages and were unable to anticipate the defensive reactions that in fact occurred. Furthermore, these estimates did not improve after participants had been explained the dynamics of threatening communication as well as what the effects of the threatening communication had been in reality. CONCLUSIONS: These findings are consistent with the hypothesis that the effectiveness of threatening health messages is intuitively appealing. What is more, providing empirical evidence against the use of threatening health messages has very little effect on this intuitive appeal.

An artificially intelligent chat agent that answers adolescents' questions related to sex, drugs, and alcohol: an exploratory study.

PURPOSE: The aim of this study was to investigate if and how an artificially intelligent chat agent (chatbot) that answers questions about sex, drugs, and alcohol is used and evaluated by adolescents, especially in comparison with information lines and search engines. METHODS: A sample of 929 adolescents (64% girls, mean age = 15), varying in urbanization level and educational level, participated in this study. Use of the chatbot was objectively tracked through server registrations (e.g., frequency and duration of conversations with the chatbot, the number and topics of queries), and a web-based questionnaire was used to evaluate the chatbot (e.g., the perception of anonymity, conciseness, ease of use, fun, quality and quantity of information, and speed) and to compare it with information lines and search engines. RESULTS: The chatbot reached high school attendees in general and not only adolescents with previous experience related to sex, drugs, or alcohol; this is promising from an informed decision-making point of view. Frequency (M = 11) and duration of conversations (3:57 minutes) was high and the chatbot was evaluated positively, especially in comparison with information lines and search engines. CONCLUSION: The use of chatbots within the field of health promotion has a large potential to reach a varied group of adolescents and to provide them with answers to their questions related to sex, drugs, and alcohol.

Social cognitive determinants of ecstasy use to target in evidence-based interventions: a meta-analytical review.

AIMS: The health hazards and prevalence of ecstasy use have been documented in two decades of research, but no review reporting on potentially modifiable antecedents of use is available. The aim of this study was to integrate systematically research identifying cognitive correlates of ecstasy use. Such research has the potential to identify targets for evidence-based interventions designed to discourage use. METHODS: The databases PsycINFO and MedLine were searched, inclusion criteria applied to resulting hits, and descendency and ancestry approaches applied to the selected publications. Reported associations between cognitive determinants, including intention to use and ecstasy use measures, were synthesized by calculating a weighted mean effect size, r. RESULTS: The pattern of associations lent support both to the theory of planned behaviour (TPB) and the expectancy approach as descriptions of potentially useful determinants. Attitudes were associated most strongly with intention and use, followed by subjective norm and perceived behavioural control. CONCLUSIONS: Consideration of the strength of associations and the potential modifiability of identified cognitions suggests that evidence-based interventions to discourage ecstasy use should target negative expectancies, perceived behavioural control and anticipated regret, and consider tailoring perceived behavioural control elements.