Ivo Vlaev

Imperial College London | Imperial · Department of Surgery and Cancer

Optimizing vaccine uptake is a public health challenge that requires the implementation of effective strategies. The asymmetric dominance (or decoy) effect describes the increasing likelihood of selecting an option when a clearly inferior alternative is offered. Therefore, we aimed to test the impact of offering decoy alternatives—less convenient v...

This study investigates pro-environmental behaviour through a personality-focused approach as well as the role of emotional engagement with environmental issues, specifically through affective commitment. Using structural equation modelling, data from an online survey of 669 participants were analyzed to explore the direct and indirect effects of p...

Developing countries, with limited monitoring and auditing capabilities, face significant tax evasion issues. This study examines the impact of various text message combinations on promoting tax compliance, particularly in encouraging service providers to submit monthly sales tax returns in Khyber Pakhtunkhwa, Pakistan. A randomised controlled tria...

Background Patient complaints in healthcare settings can provide feedback for monitoring and improving healthcare services. Behavioural responses to complaints (e.g., talking or apologising to a patient) can influence the trajectory of a complaint for instance, whether a complaint is escalated or not. We aimed to explore healthcare professional (HC...

Regular testing using rapid antigen lateral flow tests (LFTs) was an important prevention strategy during the COVID-19 pandemic. However, falsification of home LFTs was a concern. Using a large quota-representative sample of adults ( n = 1295) in England, we conducted a vignette survey consisting of four hypothetical scenarios of LFT falsification...

The factors that influence volunteerism are still insufficiently investigated today. What motivates people to engage as volunteers, and how can their willingness to do so be increased through the application of behavioural psychology in marketing campaigns? This study analyses the possibility to influence volunteer participation by applying behavio...

Gambling messaging is one potential component of a public health approach towards reducing gambling-related harm (GRH). This systematic review examined the effectiveness of existing public health gambling messaging interventions. Four databases were searched from inception to June 2023. Twenty-one papers met inclusion criteria. Studies were conduct...

Background It is challenging to predict long-term outcomes of interventions without understanding how they work. Health economic models of public health interventions often do not incorporate the many determinants of individual and population behaviours that influence long term effectiveness. The aim of this paper is to draw on psychology, sociolog...

During the COVID-19 pandemic, many organisations worldwide asked their employees to accept a temporary salary reduction to manage the financial consequences of the unprecedented event. In this paper, we use a CEO’s salary reduction announcement to all employees and investigate whether a behaviour change intervention using five selected Behaviour Ch...

Background The path of a complaint and patient satisfaction with complaint resolution is often dependent on the responses of healthcare professionals (HCPs). It is therefore important to understand the influences shaping HCP behaviour. This systematic review aimed to (1) identify the key actors, behaviours and factors influencing HCPs’ responses to...

Background Gambling has been identified as an important public health issue. Independently developed public health gambling messaging is one potential component of a public health approach toward reducing gambling-related harm. The aim of this review was to systematically examine the evidence for the effectiveness of existing public health gambling...

Optimising vaccine uptake is a public health challenge and requires effective strategies. The asymmetric dominance (or decoy) effect describes the increasing likelihood of choosing an alternative when an inferior alternative is offered. Therefore, we aimed to test the impact of offering decoy alternatives, less convenient vaccination appointments,...

Using the Theoretical Domains Framework (TDF), this rapid review coded the barriers and facilitators to binge-watching and identified corresponding behaviour change techniques (BCTs) for intervention purposes. Twenty-nine studies reporting influences on binge-watching fulfilled the inclusion criteria and passed quality appraisal checks. Data were e...

Clear communication is vital for adopting public health interventions that promote protective behaviours against respiratory infections. This systematic review and network meta-analysis assessed the effectiveness of these interventions using behavioural science frameworks, including MINDSPACE contextual influencers and behaviour change techniques (...

During the COVID-19 pandemic, the term “behavioural fatigue” became the centre of policy debates in Great Britain. These debates involved deciding when to go into lockdown and whether behavioural interventions could be effective. Behavioural interventions can only succeed where people’s capabilities, opportunities, and motivations to perform target...

Emotions powerfully, predictably, and pervasively influence decision making. The risk-as-feelings hypothesis states that two kinds of emotions are important in decision-making, anticipatory emotions and anticipated emotions. We empirically investigated whether and how anticipatory and anticipated emotions may change as a function of outcome values...

Previous observational studies have indicated that social influences, such as arising from herding-like behaviour, can contribute to medical errors. In this study, we experimentally examined whether general practitioners (GPs) would follow incorrect prescription recommendations from fellow GP or specialists. To investigate this, we conducted an onl...

Citation: Halabi, N.; Hristova, V.; Vlaev, I. Milking the Alternatives: Understanding Coffee Consumers' Preferences for Non-Dairy Milk. Abstract: Consumer interest in plant-based milk alternatives is growing, despite extra charges in coffeehouses. While much research exists on non-dairy alternatives, plant-based milks in coffee drinks remain unders...

Purpose The aim of this study is to utilise the Theoretical Domains Framework (TDF) to identify the main barriers and facilitators of positive attitude towards trying Virtual Active Sports (VAS). Design/methodology/approach 200 individuals took part in an online cross-sectional survey based on 11 domains within the TDF. Linear logistic regression...

It is commonly suggested that patients’ subjective well-being (SWB) can be affected by pre-treatment conditions and treatment experiences, and hence SWB can be used to measure and improve healthcare quality. With data collected in a hospital in the UK ( N = 446), we investigated the determinants of patients’ SWB and evaluated its use in healthcare...

This investigation uncovers the factors influencing financial capability by utilizing behavioural science and ethnography. The study employs a representative sample from across the United Kingdom with a total of 72 households. This presents a unique opportunity to establish how the general population understands and utilises money, their views and...

This research note addresses a significant gap in the literature regarding the underlying mechanisms of purchase decision-making that lead to unplanned and impulse purchases. Although several papers have highlighted the differences between the two purchase types, recent academic publications continue to use those terms interchangeably. Through a sy...

This study introduces a new randomized field experiment exploring the impact of offering a decoy charity donation incentive together with a monetary reward to increase response rates in an online survey about coronavirus fears. The study used a two-stage approach, starting with a preliminary survey to investigate participant attitudes toward differ...

This study introduces a new randomized field experiment exploring the impact of offering a decoy charity donation incentive together with a monetary reward to increase response rates in an online survey about coronavirus fears. The study used a two-stage approach, starting with a preliminary survey to investigate participant attitudes toward differ...

During the COVID-19 pandemic, lateral flow tests (LFTs) were used to regulate access to work, education, social activities, and travel. However, falsification of home LFT results was a concern. Falsification of test results during an ongoing pandemic is a sensitive issue. Consequently, respondents may not answer truthfully to questions about LFT fa...

Background Across developing countries poor sanitation is associated with disease often found widespread in rural populations. Objectives This objective of this study was to conduct a formative research and feasibility evaluation of the behavioural intervention designed to improve latrine use in rural India. Methods Study conducted in four villag...

The study investigates how people's tendency to avoid action, known as "omission bias," influences their financial decisions, specifically in the context of debt repayment to the UK government. Using a randomized controlled trial, we communicated with individuals who owed money, employing two distinct message framings. The omission‐framed message s...

A significant number of years of healthy life are lost globally due to poor behavioural and lifestyle choices, such as unhealthy diet, physical inactivity, tobacco use, and the harmful use of alcohol (World Health Organization, Global health risks: Mortality and burden of disease attributable to selected major risks, 2009). These are major risk fac...

Background. Oxygen is one of the most commonly used emergency therapies. Like other therapies, oxygen can cause harm if used inappropriately. During the COVID-19 pandemic, guidelines were released to optimise oxygen and medication use. In the current study, we examine whether oxygen and medication use during the first wave of the COVID-19 pandemic...

Background There has been a rapid increase in the number of, and demand for, organisations offering behavioural science advice to government over the last ten years. Yet we know little of the state of science and the experiences of these evidence providers. Aims and objectives To identify current practice in this emerging field and the factors tha...

Background As regular testing using rapid lateral flow device (LFD) tests became common practice during the COVID-19 pandemic, there was concern that some individuals were falsifying at-home test results. Falsification behaviours run counter to moral and ethical obligations of preventing harm, collective responsibility, and adherence to behavioural...

Background A key component for control of COVID-19 transmission was regular testing using lateral flow device (LFD) tests. However , as home self-testing using LFDs became common practice, there was concern that some people were falsifying test results. Responses to direct questioning surveys that probe sensitive behaviours are often compromised b...

Background The path of a complaint and patient satisfaction with complaint resolution is often dependent on healthcare professionals’ (HCPs) first response. It is therefore important to understand the influences shaping HCP behaviour. This systematic review aimed to (1) identify the key actors, behaviours and factors influencing HCPs’ responses to...

We conducted an independent evaluation on the effectiveness of an organisational-level monetary incentive to encourage small and medium-sized enterprises (SMEs) to improve employees’ health and wellbeing. This was A mixed-methods cluster randomised trial with four arms: high monetary incentive, low monetary incentive, and two no monetary incentive...

Humans discount delayed relative to more immediate reward. A plausible explanation is that impatience arises partly from uncertainty, or risk, implicit in delayed reward. Existing theories of discounting-as-risk focus on a probability that delayed reward will not materialize. By contrast, we examine how uncertainty in the magnitude of delayed rewar...

Introduction: Bystanders' interventions improve chances of survival from out-of-hospital cardiac arrest (OHCA) before Emergency Medical Services arrive. Some areas in England are of concern. These high-risk areas have a higher incidence of cardiac arrest combined with lower-than-average bystander CPR rates and are characterised by higher proportio...

Background: This study explores the potential for behavioural economics techniques called 'nudges' to encourage the use of HIV pre-exposure prophylaxis (PrEP) by overseas-born men who have sex with men (MSM) in Australia. We investigated the preferences of overseas-born MSM for different nudges and the effect of nudges on reported likelihood of se...

Households are currently struggling to keep up financial obligations with limited funds held away in savings account, however, the impact of interventions, such as financial education have demonstrated mixed efficacy. This study examines how behavioural interventions can produce substantial outcomes when using a holistic perspective of behaviour an...

Objectives Conduct a formative research and feasibility evaluation of behavioural intervention designed to improve latrine use in rural India. Methods Study conducted in four villages of Rajasthan, where latrine use is low and open defecation may spread disease. To identify the intervention, we conducted a literature review, a survey of 497 househo...

Background: Additional approaches to HIV prevention and management, such as Nudgeathons, are required to increase access to HIV pre-exposure prophylaxis (PrEP) among overseas-born men who have sex with men (MSM). Methods: In September 2021, we conducted a 4-h online Nudgeathon, wherein four teams co-designed behaviourally informed adverts to imp...

BACKGROUND There is consistent evidence that non-adherence is a significant problem associated with worse clinical outcomes, higher downstream re-hospitalization rates and a higher use of resources. A potential innovative strategy that has been found successful at improving patient medication adherence is the use of gamification. OBJECTIVE The stu...

Background Medical nonadherence is a significant problem associated with worse clinical outcomes, higher downstream rehospitalization rates, and a higher use of resources. To improve medication adherence, it is vital for researchers and practitioners to have a solid theoretical understanding of what interventions are likely to work. To achieve this...

Background: This study explores the potential for behavioural economics techniques called 'nudges' to encourage the use of HIV pre-exposure prophylaxis (PrEP) by overseas-born men who have sex with men (MSM) in Australia. We investigated the preferences of overseas-born MSM for different nudges and the effect of nudges on reported likelihood of se...

The aim of the study is to evaluate the interventions examining music exposure’s effects on prosocial behaviour, to identify the behaviour change techniques (BCTs) through which they change it, and to examine the mechanisms of action (MoAs) that mediate the relationship between music exposure and prosocial behaviour. The review identified 15 resear...

Small financial incentives have been proven effective at promoting healthy behaviours across medicine, including in psychiatry. There are a range of philosophical and practical objections to financial incentives. Drawing on the existing literature, specifically attempts to use financial incentives to promote antipsychotic adherence, we propose a ‘p...

Background Hospital decision-makers have limited resources to implement quality improvement projects. To decide which interventions to take forward, trade-offs must be considered that inevitably turn on stakeholder preferences. The multi-criteria decision analysis (MCDA) approach could make this decision process more transparent. Method An MCDA was...

Background Healthy diet, weight control and physical activity to reduce obesity can be motivated by financial incentives (FI). Behavioral-economic approaches may improve the incentivization effectiveness. This study compares and ranks the effectiveness of standard and behavioral incentivization for healthy diet, weight control, and physical activit...

Objectives Achieving high vaccination coverage is vital to the efforts of curbing the impact of the COVID-19 pandemic on public health and society. This study tested whether communicating the social benefit through community protection for friends and family members versus overall society, affects vaccination intention and perception among a sample...

Purpose of Review This scoping review summarises the literature on HIV prevention and management interventions utilizing behavioural economic principles encapsulated in the MINDSPACE framework. Recent Findings MINDSPACE is an acronym developed by the UK’s behavioural insights team to summarise nine key influences on human behaviour: Messenger, Inc...

Behavioral economics and its applied branch “nudging” can improve individual choices in various health care settings. However, there is a paucity of research using nudges to improve regular testing for HIV and other sexually transmitted infections (STIs). The study examined which reminder system and message type men who have sex with men (MSM) pref...

Providing healthcare workers with cost information about the medications they prescribe can influence their decisions. The current study aimed to analyse the impact of two nudges that presented cost information to prescribers through a hospital’s electronic prescribing system. The nudges were co-created by the research team: four behavioural scient...

This experimental study investigated factors that influence cheating in health literacy surveys. The objective was to predict who is most likely to cheat using Google in online knowledge surveys. The experiment randomly assigned 265 participants into three research conditions. The first group completed a pen-and-paper version of the health literacy...

Objectives Incentives have been effectively used in several healthcare contexts. This systematic review aimed to ascertain whether incentives can improve antipsychotic adherence, what ethical and practical issues arise and whether existing evidence resolves these issues. Design Systematic review of MEDLINE, EMBASE and PsycINFO. Searches on 13 Janu...

When the COVID-19 pandemic caused face-to-face meetings to be cancelled, an industry-sponsored educational programme, designed to develop skills and expand knowledge of young experts in oncology and urology, was forced to partially move from face-to-face setting to virtual meetings. In our outcomes analysis, we aimed to better understand what drive...

Background: Social media platforms, such as Facebook, Twitter, and Instagram, are being increasingly used to deliver public health interventions. Despite the high level of research interest, there is no consensus or guidance on how to report on social media interventions. Reporting guidelines that incorporate elements from behavior change theories...

Providing healthcare workers with cost information about the medications they prescribe can influence their decisions, particularly when that information is provided at the very moment they are faced with a prescribing decision. The current study aimed to analyse the impact of nudges that presented cost information to prescribers through their orga...

The last decade has seen numerous policy reforms to emplace person-centered social care. Consequently, the public has been given more information, choice, and autonomy to decide how best they want to be cared for later in life. Despite this, adults generally fail to plan or prepare effectively for their future care needs. Understanding the behavior...

The coronavirus disease (COVID-19) pandemic has highlighted the link between individual behavior and public health, along with the importance of evidence-based efforts to promote prosocial individual behavior. Insights from behavioral science can inform the design of effective behavior change techniques, or nudges, to influence individual behavior....

Background The main purpose of this study was to describe the latent structure of pregnancy perception by investigating the role of risks and medical examinations in pregnancy perception across the sexes and pregnancy status. Methods Study 1 developed a questionnaire based on the responses of 29 young adults on their perception of pregnancy. Study...

This case study describes a design thinking workshop to develop conceptual prototypes for interventions that may increase hand hygiene in hospital settings. The workshop was held in London, United Kingdom. The workshop brought together nurses, doctors, and infection prevention/control staff with experience working in hospital settings along with be...

Background: The benefits of medication optimization are largely uncontroversial but difficult to achieve. Behavior change interventions aiming to optimize prescriber medication-related decisions, which do not forbid any option and that do not significantly change financial incentives, offer a promising way forward. These interventions are often ref...

Background Research conducted in the United States suggests that two primes (citrus smells and pictures of a person's eyes) can increase hand gel dispenser use on the day they are introduced in hospital. The current study, conducted at a hospital in the United Kingdom, evaluated the effectiveness of these primes, both in isolation and in combinatio...

The article presents the results of a field experiment that uses ‘nudge’ type influences as the content of text messages targeting a specific group of debtors of one of the fast loans companies operating in Bulgaria. This is a group consisting of so-called ‘contactless’ clients, the ones that stop paying their instalments and cut all the communicat...

Previous research has shown that risk preferences are sensitive to the financial domain in which they are framed. In the present study we explore whether the effect of valence priming on risk taking is moderated by the financial context under consideration. A total of 260 participants completed an online questionnaire where risky choices were elici...

To reduce the spread of COVID-19, governments around the world have recommended or required minimum physical distancing between individuals, as well as either mandating or recommending the use of face coverings (masks) in certain circumstances. When multiple risk reduction activities can be adopted, people may engage in risk compensation by respond...

The Behavior Change Wheel is the most comprehensive and practically useful methodology available for developing behavior change interventions. The current article demonstrates how it can be applied to optimize pro-environmental behaviors and, in so doing, give interventionists access to a rigorous set of theories and techniques for systematically d...

We investigated which population groups were impacted most in terms of physical activity levels during the restrictions applied during the COVID-19 pandemic. We surveyed UK residents, sampled through users of a rewards-for-exercise app (Sweatcoin; n = 749) and an online panel (Prolific; n = 907). Of the app users, n = 487 further provided daily ste...