Because I'm worth it: a lab-field experiment on the spillover effects of incentives in health

We conduct a controlled lab-field experiment to directly test the short-run spillover effects of one-off financial incentives in health. We consider how incentives affect effort in a physical activity task – and then how they spillover to subsequent eating behaviour. Compared to a control group, we find that low incentives increase effort and have little effect on eating behaviour. High incentives also induce more effort but lead to significantly more excess calories consumed. The key behavioural driver appears to be the level of satisfaction associated with the physical activity task, which ‘licensed’ highly paid subjects to indulge in more energy-dense food

Like ripples on a pond: behavioral spillovers and their implications for research and policy

No behavior sits in a vacuum, and one behavior can greatly affect what happens next. We propose a conceptual frame within which a broad range of behavioral spillovers can be accounted for when applying behavioral science to policy challenges. We consider behaviors which take place sequentially and are linked, at a conscious or unconscious level, by some underlying motive. The first behavior leads to another behavior which can either work in the same direction as the first (promoting spillover), or push back against it (permitting or purging spillover). Looking through this conceptual lens at the existing evidence, we find pervasive evidence for all kinds of spillover effects across a variety of fields and domains. As a result, behavioral scientists, especially those seeking to inform policy, should try to capture all the ripples from one behavior to the next when a pebble of intervention is thrown in the pond, and not just at the immediate behavioral splash it makes

When the future “spills under”: general self-efficacy moderates the influence of expected exercise on present intellectual performance

We examined whether an expected future activity (exercise vs. relaxation) impacts a present behavior (performance on an intellectual task) that occurs prior to this activity. Across two experiments (n=320 and n=466), the influence of expected exercise compared to relaxation on present intellectual performance was moderated by general self-efficacy (GSE)—a core personality trait that determines people’s confidence that they can surmount physically or intellectually challenging activities. Participants high in GSE had better intellectual performance when they were expecting to exercise versus relax, whereas the effect reversed under low GSE. Moderated mediation analyses suggested that task-focused attention (i.e., participants’ level of focus while solving the intellectual task) accounted for a significant proportion of variance between the future activity (exercise vs. relaxation) and present intellectual performance across different GSE levels. These findings document a previously unexplored channel through which future expectations shape present outcomes

Genetic and Modifiable Risk Factors Contributing to Cisplatin-Induced Toxicities

Effective administration of traditional cytotoxic chemotherapy is often limited by off-target toxicities. This clinical dilemma is epitomized by cisplatin, a platinating agent that has potent antineoplastic activity due to its affinity for DNA and other intracellular nucleophiles. Despite its efficacy against many adult-onset and pediatric malignancies, cisplatin elicits multiple off-target toxicities that can not only severely impact a patient’s quality of life, but also lead to dose reductions or the selection of alternative therapies that can ultimately affect outcomes. Without an effective therapeutic measure by which to successfully mitigate many of these symptoms, there have been attempts to identify a priori those individuals who are more susceptible to developing these sequelae through studies of genetic and nongenetic risk factors. Older age is associated with cisplatin induced ototoxicity, neurotoxicity and nephrotoxicity. Traditional genome-wide association studies have identified single nucleotide polymorphisms in ACYP2 and WFS1 associated with cisplatin-induced hearing loss. However, validating associations between specific genotypes and cisplatin-induced toxicities with enough stringency to warrant clinical application remains challenging. This review summarizes the current state of knowledge with regard to specific adverse sequelae following cisplatin-based therapy with a focus on ototoxicity, neurotoxicity, nephrotoxicity, myelosuppression and nausea/emesis. We discuss variables (genetic and nongenetic) contributing to these detrimental toxicities, and currently available means to prevent or treat their occurrence

Looking ahead: subjective time perception and individual discounting

Time discounting is at the heart of economic decision-making. We disentangle hyperbolic discounting from subjective time perception using experimental data from incentive-compatible tests to measure time preferences, and a set of experimental tasks to measure time perception. The two behavioural parameters may be related to two factors that affect how we look ahead to future events. The first is that some component of time preferences reflect hyperbolic discounting. The second factor is that non-constant discounting may also be a reflection of subjective time perception: if people’s perception of time follows a near logarithmic process (as all other physiological perceptions such as heat, sound, and light do) then all existing estimates of individual discounting will be mis-measured and incorrectly suggest “hyperbolic” discounting, even if discounting over subjective time is constant. To test these hypotheses, we empirically estimate the two distinct behavioural parameters using data collected from 178 participants to an experiment conducted at the London School of Economics Behavioural Research Lab. The results support the hypothesis that apparent non-constant discounting is largely a reflection of subjective time perception

Paying people to eat or not to eat?: carryover effects of monetary incentives on eating behaviour

There is no evidence comparing head-to-head the effects of monetary incentives to act and to abstain from acting on behaviour. We present an experiment, conducted between June and September 2012, that directly compares the effects of those two different monetary incentive schemes on eating behaviour: we evaluate incentives to eat against incentives not to eat. A large number of participants (n = 353) had bowls of sweets next to them while they watched different videos over two experimental sessions that were two days apart. Sweets eating was monitored and monetary incentives to eat or not to eat were introduced during one of the videos for participants randomly allocated to these conditions. Our results show that, while both types of incentives were effective in changing sweets-eating behaviour when they were in place, only incentives not to eat had significant carryover effects after they were removed. Those effects were still significant two days after the monetary incentives had been eliminated. We also present some additional results on personality and health-related variables that shed further light on these effects. Overall, our study shows that incentives not to eat can be more effective in producing carryover effects on behaviour in domains like the one explored here

Looking at spillovers in the mirror: making a case for "behavioural spillunders"

Behavioral spillovers refer to the influence that a given intervention targeting behavior 1 exerts on a subsequent, non-targeted, behavior 2, which may or may not be in the same domain (health, finance, etc.) as one another. So, a nudge to exercise more, for example, could lead people to eat more or less, or possibly even to give more or less to charity depending on the nature of the spillover. But what if spillovers also operate backward; that is, if the expectation of behavior 1 influences behavior 0 that precedes it? For example, a person may form an intention to exercise prompted by a policy intervention but overeat at present as a result. We define such a possibility as a "spillunder." In the proposed article, we critically review the few papers that we have identified through a narrative literature review which have demonstrated spillunder effects to date, and we propose a conceptual framework. Based on evidence about the human mind and behavior from psychology and economics, we argue that spillunder effects may be more common than the limited empirical findings suggest. We propose six representative mechanisms through which the prospect of behavior 1 may impact behavior 0: executive functions, moral licensing and moral cleansing, emotion regulation, energization, construal level, and savoring and dread. We further discuss the policy and practical implications of spillunder effects and examine methodological issues that need to be considered when empirically testing these effects. As with our earlier paper on spillovers, we aim to motivate other behavioral scientists to research behavioral spillunders more systematically and extensively, and to prompt decision makers to consider these effects when designing behavioral interventions

"Pay them if it works": discrete choice experiments on the acceptability of financial incentives to change health related behaviour.

The use of financial incentives to change health-related behaviour is often opposed by members of the public. We investigated whether the acceptability of incentives is influenced by their effectiveness, the form the incentive takes, and the particular behaviour targeted. We conducted discrete choice experiments, in 2010 with two samples (n = 81 and n = 101) from a self-selected online panel, and in 2011 with an offline general population sample (n = 450) of UK participants to assess the acceptability of incentive-based treatments for smoking cessation and weight loss. We focused on the extent to which this varied with the type of incentive (cash, vouchers for luxury items, or vouchers for healthy groceries) and its effectiveness (ranging from 5% to 40% compared to a standard treatment with effectiveness fixed at 10%). The acceptability of financial incentives increased with effectiveness. Even a small increase in effectiveness from 10% to 11% increased the proportion favouring incentives from 46% to 55%. Grocery vouchers were more acceptable than cash or vouchers for luxury items (about a 20% difference), and incentives were more acceptable for weight loss than for smoking cessation (60% vs. 40%). The acceptability of financial incentives to change behaviour is not necessarily negative but rather is contingent on their effectiveness, the type of incentive and the target behaviour

Looking ahead: subjective time perception and individual discounting

We disentangle hyperbolic discounting from subjective time perception using experimental data from incentive-compatible tests to measure time preferences, and a set of experimental tasks to measure time perception. Two behavioral parameters are related to two factors affecting how we look ahead to future events. The first is some component of time preferences reflecting hyperbolic discounting. The second factor is that non-constant discounting may also be a reflection of subjective time perception: if people’s perception of time follows a near logarithmic process (as heat, sound, and light do) then estimates of individual discounting will be mis-measured and incorrectly suggest hyperbolic discounting even if discounting over subjective time is constant. We empirically estimate the two distinct behavioral parameters using data collected from 178 participants in a lab experiment. The results support the hypothesis that apparent non-constant discounting is largely a reflection of non-linear subjective time perception

The prognostic value of systemic inflammation in patients undergoing surgery for colon cancer: comparison of composite ratios and cumulative scores

Introduction: The systemic inflammatory response has been proven to have a prognostic value. There are two methods of assessing the systemic inflammatory response composite ratios (R) and cumulative scores (S). The aim of this study was to compare the prognostic value of ratios and scores in patients undergoing surgery for colon cancer. Methods: Patients were identified prospectively in a single surgical unit. Preoperative neutrophil (N), lymphocyte (L), monocyte (M) and platelet (P) counts, CRP (C) and albumin (A) levels were recorded. The relationship between composite ratios neutrophil–lymphocyte ratio (NLR), platelet–lymphocyte ratio (PLR), lymphocyte–monocyte ratio (LMR), C-reactive protein albumin ratio (CAR) and the cumulative scores neutrophil– lymphocyte score (NLS), platelet–lymphocyte score (PLS), lymphocyte–monocyte score (LMS), neutrophil– platelet score (NPS), modified Glasgow prognostic score (mGPS) and clinicopathological characteristics, cancer-specific survival (CSS) and overall survival (OS), were examined. Results: A total of 801 patients were examined. When adjusted for tumour node metastasis (TNM) stage, NLR >5 (p < 0.001), NLS (p < 0.01), PLS (p < 0.001), LMR <2.4 (p < 0.001), LMS (p < 0.001), NPS (p < 0.001), CAR >0.22 (p < 0.001) and mGPS (p < 0.001) were significantly associated with CSS. In patients undergoing elective surgery (n = 689), the majority of the composite ratios/scores correlated with age (p < 0.01), BMI (p < 0.01), T stage (p < 0.01), venous invasion (p < 0.01) and peritoneal involvement (p < 0.01). When NPS (myeloid) and mGPS (liver) were directly compared, their relationship with CSS and OS was similar. Conclusions: Both composite ratios and cumulative scores had prognostic value, independent of TNM stage, in patients with colon cancer. However, cumulative scores, based on normal reference ranges, are simpler and more consistent for clinical use