Fruit and Vegetable Vouchers With and Without an SSB Tax

Study Overview
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Brief Summary
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We aim to examine whether a purchasing incentive for healthy foods has the same effect on dietary intake in a community with and a community without a purchasing penalty for unhealthy foods. We will perform a randomized non-inferiority trial in two locations, San Francisco (SF) and Los Angeles (LA) to test whether a voucher for purchasing fresh fruits and vegetables has a similar effect in LA and in SF, where the former does not but the latter does have a tax on sugar-sweetened beverages. Participants will be recruited from 4 neighborhoods (N=312) with 2 SF neighborhoods (exposed to the SSB tax) and 2 LA neighborhoods (not exposed to the SSB tax).

Detailed Description
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We will test the hypothesis that a positive incentive for healthy foods (fresh fruits and vegetables, F&Vs) will be utilized as effectively in a community without a purchasing penalty for unhealthy foods (a sugar-sweetened beverage [SSB] tax) as in a community with a purchasing penalty for unhealthy foods (a SSB tax). Our experiment will test the empirically-driven hypothesis in a real-world setting through a noninferiority design: comparing the impact of F&V vouchers in two counties, one without (Los Angeles) and one with (San Francisco) a SSB tax. Each study participant will receive four paper vouchers per month for a total of six months. Each of these vouchers can be redeemed for fresh or frozen fruits and vegetables at a number of specified local corner stores, supermarkets, or farmer's markets. Half of these participants will receive and spend these vouchers in an environment which has implemented a SSB tax (SF); the other half will receive and spend these same vouchers in a non-tax environment (LA). Each individual participant will be enrolled in the study for a total of seven months from initial orientation and participant consent (M0) to final data collection during final month of intervention (M6). We are using a non-inferiority trial design. We are aiming to test whether there is a significant difference in total cup-equivalents of F&V intake in LA participants as compared to SF participants when given F&V vouchers. That is, we aim to test whether the F&V voucher is less effective in LA than in SF. This is important to test because it has been purported that SF has a unique food environment with high accessibility to fresh F&V through farmer's markets and a plethora of corner stores, as well as a SSB tax that discourages less healthy foods, potentially leaving more funds for healthier F&Vs. Thus, we aim to determine the change in consumption of F&V in LA participants is non-inferiority to that of SF participants, when both are given F&V vouchers.

Official Title
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The EValuating Interventions in Diabetogenic Environments Through Natural Controlled Experiments (EVIDENCE) Trial

Conditions
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Cardiovascular Diseases

Intervention / Treatment
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* Behavioral: Fruit and vegetable voucher


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Understand English sufficiently to provide informed consent; Provision of signed and dated informed consent form; Stated willingness to comply with all study procedures and availability for the duration of the study; Any gender, aged 21 years or older; Have self-reported income ≤250% of the federal poverty level; Have regular access to a mobile phone; Have a safe and secure mailing address at which to receive vouchers; Be a resident of the Counties of San Francisco or Los Angeles as defined by official municipal boundaries. Exclusion Criteria: Currently participating in any other dietary or nutrition study that would impact his or her normal eating patterns; Currently be enrolled in and receiving EatSF, CHIVES, or Vouchers4Veggies vouchers; Has active diagnosis of cancer or congestive heart failure; Is planning to move out of San Francisco or Los Angeles in the next 12 months; Currently pregnant. Currently live with and share a food budget with a current Vouchers4Veggies, EVIDENCE, or CHIVES study participant.

Ages Eligible for Study
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Minimum Age: 21 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: San Francisco<br>Each study participant will receive four paper vouchers per month for a total of six months. Each of these vouchers can be redeemed for fresh or frozen fruits and vegetables at a number of specified local corner stores, supermarkets, or farmer's markets. The San Francisco participants will receive and spend these vouchers in an environment which has implemented a sugar-sweetened beverage tax. | Behavioral: Fruit and vegetable voucher<br>* Participants will receive four vouchers, each dated for a month, to be used on fruits and vegetables at specified local corner stores, supermarkets, and farmer's markets for a duration of six months. Each study participant will have the same intervention, as this is a non-inferiority trial to compare voucher use in LA and test whether the nutritional effects of that use are non-inferior to use in SF.<br>* Other names: Voucher;|
| Active Comparator: Los Angeles<br>Each study participant will receive four paper vouchers per month for a total of six months. Each of these vouchers can be redeemed for fresh or frozen fruits and vegetables at a number of specified local corner stores, supermarkets, or farmer's markets. The Los Angeles participants will receive and spend these vouchers in an environment which has NOT implemented a sugar-sweetened beverage tax. | Behavioral: Fruit and vegetable voucher<br>* Participants will receive four vouchers, each dated for a month, to be used on fruits and vegetables at specified local corner stores, supermarkets, and farmer's markets for a duration of six months. Each study participant will have the same intervention, as this is a non-inferiority trial to compare voucher use in LA and test whether the nutritional effects of that use are non-inferior to use in SF.<br>* Other names: Voucher;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in fruit and vegetable consumption | Change in fruit and vegetable consumption from baseline (BL), i.e., before voucher receipt, to the end of the intervention at the end of month 6 (M6), i.e., during the final month of voucher receipt, measured by two 24-hour recalls at each data collection point (BL and M6). | Month 0 to Month 6 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in nutrition quality per HEI score | Change in nutrition quality of study participants from BL to M6, measured by the Healthy Eating Index (HEI), which is calculated from two 24-hour recalls at each data collection point (BL and M6). | Month 0 to Month 6 | 
| Change in nutrition quality per AHEI score | Change in nutrition quality of study participants from BL to M6, measured by the Alternative Healthy Eating Index (AHEI), which is calculated from two 24-hour recalls at each data collection point (BL and M6). | Month 0 to Month 6 | 
| Change in SSB consumption | Change in SSB consumption from BL to M6, measured in change in fluid ounces, as measured by two 24-hour recalls at each data collection point (BL and M6). | Month 0 to Month 6 | 
| Change in overall caloric intake | Change in overall caloric intake from BL to M6, measured in change in kcal, as measured by two 24-hour dietary recalls at each data collection point (BL and M6). | Month 0 to Month 6 | 
| Overall percentage of vouchers redeemed | Overall percentage of vouchers redeemed per participant, measured by how many vouchers each participant redeemed as compared to how many vouchers they received over the 6 month intervention period. | Month 0 to Month 6 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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nutrition, fruits and vegetables, sugar-sweetened beverages