Coupons for Healthy Intake Using Variable Economic Strategies (CHIVES)

Improving diets through increased food and vegetable (F&V) consumption significantly reduces
the risk of cardiovascular disease (CVD). Programs increasing the accessibility and
affordability of F&Vs among low-income Americans have been hindered by the food consumption
cycle associated with poverty: the tendency to over-consume calories shortly after receiving
funds at the beginning of each month, draining the budget for F&V purchases, or for all food
purchases, by month's end. An emerging theory about dietary behavior suggests that providing
funds for food in smaller installments distributed throughout the month will smooth the
consumption cycle and improve healthy eating-counteracting the tendency to respond to lump
sum, once-monthly funding installments by purchasing calorie-dense foods immediately after
funds are received. The theory also suggests that funds targeted toward specific healthy
foods (e.g., F&Vs) will improve diets more than untargeted funds, despite the inconvenience
of utilizing targeted funds. We will rigorously test both hypotheses in a real-world setting
by comparing alternative approaches for delivering food purchasing vouchers. We have
established and tested the infrastructure to provide vouchers accepted by numerous food
sellers (e.g., supermarkets, corner shops) in low-income neighborhoods. Leveraging this
infrastructure, we will conduct a randomized trial with a two-by-two factorial design,
comparing $20 of vouchers valid for one month to four $5 vouchers each valid for a sequential
week of the month (lump sum versus distributed funding), and comparing vouchers restricted to
F&V purchases to vouchers redeemable for any food (targeted versus untargeted funding).
Low-income adults (N=288) recruited through our community partners will be randomized to one
of four 6-month interventions: monthly targeted, monthly untargeted, weekly targeted, or
weekly untargeted vouchers. Participants will be assessed through efficient verbal 24-hour
dietary recalls validated among low-literacy populations, to determine daily consumption of
F&Vs and metrics of overall dietary quality at months 0, 6 and 12 (6 months after vouchers
end). Additional surveys will identify moderators and mediators of dietary improvement.