Designing and Validating a Novel Method for Assessing Delay Discounting Associated With Health Behaviors: Ecological Momentary Assessment Study

BACKGROUND

Delay discounting quantifies an individual's preference for smaller, short-term rewards over larger, long-term rewards and represents a transdiagnostic factor associated with numerous adverse health outcomes. Rather than a fixed trait, delay discounting may vary over time and place, influenced by individual and contextual factors. Continuous, real-time measurement could inform adaptive interventions for various health conditions.

OBJECTIVE

The goals of this paper are 2-fold. First, we present and validate a novel, short, ecological momentary assessment (EMA)-based delay discounting scale we developed. Second, we assess this tool's ability to reproduce known associations between delay discounting and health behaviors (ie, substance use and craving) using a convenience-based sample.

METHODS

Participants (N=97) were adults (age range 18-71 years), recruited on social media. In phase 1, data were collected on participant sociodemographic characteristics, and delay discounting was evaluated via the traditional Monetary Choice Questionnaire (MCQ) and our novel method (ie, 7-item time-selection and 7-item monetary-selection scales). During phase 2 (approximately 6 months later), participants completed the MCQ, our novel delay discounting measures, and health outcomes questions. The correlations between our method and the traditional MCQ within and across phases were examined. For scale reduction, a random number of items were iteratively selected, and the correlation between the full and random scales was assessed. We then examined the association between our time- and monetary-selection scales assessed during phase 2 and the percentage of assessments that participants endorsed using or craving alcohol, tobacco, or cannabis.

RESULTS

In total, 6 of the 7 individual time-selection items were highly correlated with the full scale (r>0.89). Both time-selection (r=0.71; P<.001) and monetary-selection (r=0.66; P<.001) delay discounting rates had high test-retest reliability across phases 1 and 2. Phase 1 MCQ delay discounting function highly correlated with phase 1 (r=0.76; P<.001) and phase 2 (r=0.45; P<.001) time-selection delay discounting scales. One or more randomly chosen time-selection items were highly correlated with the full scale (r>0.94). Greater delay discounting measured via the time-selection measure (adjusted mean difference=5.89, 95% CI 1.99-9.79), but not the monetary-selection scale (adjusted mean difference=-0.62, 95% CI -3.57 to 2.32), was associated with more past-hour tobacco use endorsement in follow-up surveys.

CONCLUSIONS

This study evaluated a novel EMA-based scale's ability to validly and reliably assess delay discounting. By measuring delay discounting with fewer items and in situ via EMA in natural environments, researchers may be better able to identify individuals at risk for poor health outcomes.

Identifying the Most Effective Recruitment Strategy Using Financial Reimbursements for a Web-Based Peer Network Study With Young People Aged 16-18 Years: Protocol for a Randomized Controlled Trial

BACKGROUND

Peers are an important determinant of health and well-being during late adolescence; however, there is limited quantitative research examining peer influence. Previous peer network research with adolescents faced methodological limitations and difficulties recruiting young people.

OBJECTIVE

This study aims to determine whether a web-based peer network survey is effective at recruiting adolescent peer networks by comparing 2 strategies for reimbursement.

METHODS

This study will use a 2-group randomized trial design to test the effectiveness of reimbursements for peer referral in a web-based cross-sectional peer network survey. Young people aged 16-18 years recruited through Instagram, Snapchat, and a survey panel will be randomized to receive either scaled group reimbursement (the experimental group) or fixed individual reimbursement (the control group). All participants will receive a reimbursement of Aus $5 (US $3.70) for their own survey completion. In the experimental group (scaled group reimbursement), all participants within a peer network will receive an additional Aus $5 (US $3.70) voucher for each referred participant who completes the study, up to a maximum total value of Aus $30 (US $22.20) per participant. In the control group (fixed individual reimbursement), participants will only be reimbursed for their own survey completion. Participants' peer networks are assessed during the survey by asking about their close friends. A unique survey link will be generated to share with the participant's nominated friends for the recruitment of secondary participants. Outcomes are the proportion of a participant's peer network and the number of referred peers who complete the survey. The required sample size is 306 primary participants. Using a multilevel logistic regression model, we will assess the effect of the reimbursement intervention on the proportion of primary participants' close friends who complete the survey. The secondary aim is to determine participant characteristics that are associated with successfully recruiting close friends. Young people aged 16-18 years were involved in the development of the study design through focus groups and interviews (n=26).

RESULTS

Participant recruitment commenced in 2022.

CONCLUSIONS

A longitudinal web-based social network study could provide important data on how social networks and their influence change over time. This trial aims to determine whether scaled group reimbursement can increase the number of peers referred. The outcomes of this trial will improve the recruitment of young people to web-based network studies of sensitive health issues.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/44813.

Research Compensation and Enhanced Contacts in Studies With Persons Who Use Drugs: Lessons From the COVID-19 Pandemic Demand a Reset

Policy changes resulting from the coronavirus 2019 (COVID-19) pandemic have had a substantial and positive impact on the clinical care of persons with opioid use disorder. These innovative paradigm shifts created a ripe environment for re-evaluating traditional approaches to recruiting and retaining persons who use drugs into research studies. For example, changes to methadone prescribing requirements and authorization of buprenorphine prescriptions via telehealth have both increased access to medications. In this commentary, we contribute to ongoing conversations about the ethics of compensation for participants in addiction-related clinical research and share methods of payment that proved successful in research performed during the pandemic. We also discuss approaches to enrollment and follow-up that were implemented during the height of COVID restrictions. These approaches may mutually benefit both participants and researchers in a post-pandemic era.

Policy Packages and Policy Space: Lessons from COVID-19

This paper uses the onset of COVID-19 to examine how countries construct their policy packages in response to a severe negative shock. We use several new datasets to track the use of a large variety of policy tools: announced fiscal stimulus (both above- and below-the-line), monetary policy (through interest rates, asset purchases, liquidity support and swap lines), foreign currency intervention, adjustments to macroprudential regulations (including the countercyclical capital buffer) and changes in capital controls (on inflows and outflows). The results suggest that pre-existing policy space was usually more important than other country characteristics and the extent of "stress" (in economic, financial, and health measures) in determining how a country responded to COVID-19. The notable exception is for fiscal stimulus, for which existing policy space did not act as a significant constraint in advanced economies. This is a sharp contrast to results for earlier episodes-although advanced economies with higher debt levels may have been constrained in how they provided stimulus (with more below-the-line commitments). Moreover, the use of (and space available) for each policy tool usually did not affect a country's use of other policies. This suggests that countries are not coordinating their tools optimally in an integrated framework, especially when policy space is limited for certain tools.

No Money, No Problem: Enhanced Reward Positivity in the Absence of Monetary Reward

The reward-related positivity (RewP) is an event-related potential (ERP) with a positive amplitude occurring approximately 250–350 ms post-feedback at frontocentral electroencephalogram (EEG) electrode sites. The RewP is typically elicited in monetary gambling tasks and has a relatively larger amplitude for positive vs. negative outcomes. However, the extent to which RewP amplitude is modulated by non-monetary feedback is less clear. To address this issue, EEG was used to record reward-related electrocortical activity during a simple non-monetary gambling task. We hypothesized that the RewP would be enhanced for non-monetary wins relative to losses, which was supported by the results. In our supplementary material, we provide additional analyses suggesting that this effect was not observed for the P3. In sum, RewP amplitudes were larger for positive (nonmonetary) feedback relative to negative feedback at frontocentral electrode sites—suggesting that monetary reward is not necessary to elicit the RewP.

Treatment of hepatitis C virus leads to economic gains related to reduction in cases of hepatocellular carcinoma and decompensated cirrhosis in Japan

Hepatocellular carcinoma (HCC) is a serious complication of hepatitis C virus (HCV) infection. Sustained virologic response (SVR) for HCV is associated with a reduction in cirrhosis, HCC and mortality and their associated costs. Japanese HCV patients are older with higher prevalence of HCC. Here we used a decision-analytic Markov model to estimate the economic benefit of HCV cure by reducing HCC and DCC burden in Japan. A cohort of 10 000 HCV genotype 1b (GT1b) Japanese patients was modelled with a hybrid decision tree and Markov state-transition model capturing natural history of HCV over a lifetime horizon. Treatment options were approved all-oral direct-acting anti-virals (DAAs) vs no treatment. Treatment efficacy was based on clinical trials and transition rates and costs obtained from Japan-specific data. Cases of HCC, decompensated cirrhosis (DCC) and quality-adjusted life years (QALYs) were projected for patients treated with DAAs vs NT. QALYs were monetized using a willingness-to-pay threshold of ¥4-to-¥6 million. Incremental savings with treatment were calculated by adding the projected cost of complications avoided to the monetized gains in QALYs. The model showed that DAA treatment vs no treatment, reduces 2057 cases of HCC and 1478 cases of decompensated cirrhosis and saves ¥850 446.73 and ¥338 229.90 per patient (ppt). Additionally, treatment can lead to additional 2.64 QALYs gained per patient. The indirect economic gains associated with treatment-related QALY improvements were ¥10 576 000, ¥13 220 000 and ¥15 864 000 ppt (willingness-to-pay thresholds of ¥4 million, ¥5 million and ¥6 million). Total economic savings of treatment with DAAs (vs no treatment) was ¥7 526 372.63, ¥10 170 372.63 and ¥12 814 372.63, at these different willingness-to-pay thresholds. In conclusion treatment of HCV GT1b with all-oral DAAs in Japan can lead to significant direct and indirect savings related to avoidance of HCC and DCC.

Disrupted cortico-limbic connectivity during reward processing in remitted bipolar I disorder

OBJECTIVES

Bipolar disorder (BD) is associated with elevated reward sensitivity and persistent positive affect, yet the neural mechanisms underlying these patterns are not well understood. In the present study, we examined putative disruptions in communication within a well-known cortico-limbic reward circuit during reward processing as a potential contributing mechanism to these symptoms.

METHODS

The present investigation employed a within- and between-subjects design utilizing a monetary and social incentive delay task among adults with bipolar disorder type I (BD; N = 24) and a healthy non-psychiatric control group (HC; N = 25) during functional magnetic resonance imaging (fMRI). Participants in the BD group were remitted at the time of testing.

RESULTS

Functional connectivity analyses revealed increased connectivity between the ventral striatum (VS) seed region and orbitofrontal cortex (OFC) as well as the amygdala during processing of reward receipt in the BD group. After omission of expected rewards, the BD group showed decreased functional connectivity between the VS and a medial frontopolar cortex (mFPC) region associated with consideration of behavioral alternatives. Follow-up analyses within the BD group showed that increased VS-OFC connectivity after reward receipt, and decreased VS-mFPC connected after reward omission, were associated with higher levels of subthreshold mania symptoms.

CONCLUSIONS

Results point toward potential mechanisms implicated in elevated reward sensitivity in BD. Enhanced VS-OFC connectivity after reward receipt may be involved in elevated valuation of rewards whereas blunted VS-mFPC connectivity after reward omission may reflect a failure to consider behavioral alternatives to reward pursuit.

A Systematic Review of Financial Incentives for Physical Activity: The Effects on Physical Activity and Related Outcomes

The aim of this review is to give an overview of the available evidence on the effects of financial incentives to stimulate physical activity. Therefore, a systematic literature search was performed for randomized trials that investigate the effects of physical-activity-related financial incentives for individuals. Twelve studies with unconditional incentives (eg, free membership sport facility) and conditional incentives (ie, rewards for reaching physical-activity goals) related to physical activity were selected. Selected outcomes were physical activity, sedentary behavior, fitness, and weight. Results show that unconditional incentives do not affect physical activity or the other selected outcomes. For rewards, some positive effects were found and especially for rewards provided for physical-activity behavior instead of attendance. In conclusion, rewards seem to have positive effects on physical activity, while unconditional incentives seem to have no effect. However, it should be kept in mind that the long-term effects of financial incentives are still unclear.

Brain reward system's alterations in response to food and monetary stimuli in overweight and obese individuals

The brain's reward system is crucial to understand obesity in modern society, as increased neural responsivity to reward can fuel the unhealthy food choices that are driving the growing obesity epidemic. Brain's reward system responsivity to food and monetary rewards in individuals with excessive weight (overweight and obese) versus normal weight controls, along with the relationship between this responsivity and body mass index (BMI) were tested. The sample comprised 21 adults with obesity (BMI > 30), 21 with overweight (BMI between 25 and 30), and 39 with normal weight (BMI < 25). Participants underwent a functional magnetic resonance imaging (fMRI) session while performing two tasks that involve the processing of food (Willing to Pay) and monetary rewards (Monetary Incentive Delay). Neural activations within the brain reward system were compared across the three groups. Curve fit analyses were conducted to establish the association between BMI and brain reward system's response. Individuals with obesity had greater food-evoked responsivity in the dorsal and ventral striatum compared with overweight and normal weight groups. There was an inverted U-shape association between BMI and monetary-evoked responsivity in the ventral striatum, medial frontal cortex, and amygdala; that is, individuals with BMIs between 27 and 32 had greater responsivity to monetary stimuli. Obesity is associated with greater food-evoked responsivity in the ventral and dorsal striatum, and overweight is associated with greater monetary-evoked responsivity in the ventral striatum, the amygdala, and the medial frontal cortex. Findings suggest differential reactivity of the brain's reward system to food versus monetary rewards in obesity and overweight. Hum Brain Mapp 38:666-677, 2017. © 2016 Wiley Periodicals, Inc.

Incentives to promote breastfeeding: a systematic review

BACKGROUND AND OBJECTIVES

Few women in industrialized countries achieve the World Health Organization's recommendation to breastfeed exclusively for 6 months. Governments are increasingly seeking new interventions to address this problem, including the use of incentives. The goal of this study was to assess the evidence regarding the effectiveness of incentive interventions, delivered within or outside of health care settings, to individuals and/or their families seeking to increase and sustain breastfeeding in the first 6 months after birth.

METHODS

Searches of electronic databases, reference lists, and grey literature were conducted to identify relevant reports of published, unpublished, and ongoing studies. All study designs published in English, which met our definition of incentives and that were from a developed country, were eligible for inclusion. Abstract and full-text article review with sequential data extraction were conducted by 2 independent authors.

RESULTS

Sixteen full reports were included in the review. The majority evaluated multicomponent interventions of varying frequency, intensity, and duration. Incentives involved providing access to breast pumps, gifts, vouchers, money, food packages, and help with household tasks, but little consensus in findings was revealed. The lack of high-quality, randomized controlled trials identified by this review and the multicomponent nature of the interventions prohibited meta-analysis.

CONCLUSIONS

This review found that the overall effect of providing incentives for breastfeeding compared with no incentives is unclear due to study heterogeneity and the variation in study quality. Further evidence on breastfeeding incentives offered to women is required to understand the possible effects of these interventions.