Impact Measurement for Mobile Markets: A Framework for Funders

Funders reasonably want to understand what their investments will achieve. But impact measurement in mobile markets requires realistic expectations about what can be measured, how confidently, and at what cost. This framework helps funders and operators align on appropriate metrics.

Levels of Measurement

Mobile market impact can be measured at several levels, each with different level of confidence and with cost implications.

Output metrics measure what the program does: number of stops operated, how many customers served, transaction volume completed, pounds of produce distributed, SNAP/EBT redemptions processed. These are highly measurable, relatively inexpensive to track, and directly controllable by the program.

Outcome metrics measure changes for participants: increased produce access, improved dietary intake, changes in food security status. These require customer surveys or tracking, will cost more to measure, will be more qualitative than quantitative, and illustrate the correlation  between the program and participant benefits.

Impact metrics measure broader effects: health improvements, reduced healthcare utilization, community-level fresh food access increases. These require sophisticated evaluation design, significant cost, and often can only suggest rather than prove causation.

Most mobile markets should measure outputs thoroughly, measure some outcomes where feasible, and be modest about claiming impact without rigorous evidence.

Core Metrics for Every Program

Regardless of program size or sophistication, track these basics.

Operational metrics: Number of market days, stops per week, hours of operation. This demonstrates program delivery.

Customer metrics: Total customers served (unique if possible), number of customers per stop, repeat customer rate. This shows reach and engagement.

Transaction metrics: Total transactions, average transaction size, SNAP/EBT transaction percentage. These reveal economic activity and population served.

Product metrics: Pounds or dollars of produce distributed, and product mix. These quantify food access provided.

Since these metrics require only basic tracking through POS systems and simple record-keeping, every program can capture them.

Outcome Metrics Worth Pursuing

For programs with capacity, additional outcome measurement can add  value.

Customer food access surveys: Ask customers whether and how the mobile market has changed their food access, what they would do without it, and how it affects their shopping and eating habits. Simple surveys administered periodically capture self-reported outcomes.

Dietary intake indicators: Brief surveys asking about fruit and vegetable consumption frequency can track changes over time for repeat customers. Validated instruments do exist (dietary screeners, for example).

Food security status: Periodically using standardized food security screening (like the Hunger Vital Sign) with regular customers can indicate to what extent participation correlates with improved food security.

Customer demographics: Understanding who you serve, including income levels, age, household composition will demonstratemobile market reach to specific  populations. Be sure to respect the privacy of individuals.

Health Outcome Measurement

For programs seeking health outcome evidence, the bar is higher.

Partner with health systems that can track patient participation and correlate with clinical data (blood pressure, glucose, weight). This requires data sharing agreements and research infrastructure.

Use comparison groups where possible. Outcomes for mobile market participants compared to similar non-participants will strengthen causal claims.

Track over a sufficient amount of time. Health changes take months to years, not weeks. Short-term measurement may miss the real impact.

Accept limitations. Definitive proof that mobile markets cause specific health outcomes is methodologically difficult. Promising evidence with appropriate caveats is realistic, while iron-clad proof usually isn't.

What Funders Should Ask For

Reasonable funder expectations will likely include several things:

• Core output metrics from every funded program is the baseline of accountability.

• Customer reach data demonstrating the program serves intended populations (low-income, food-insecure, specific geographic areas).

• Some outcome data for larger investments. Customer surveys and food access indicators are reasonable to expect for grants above $50,000 to $100,000.

• Realistic impact claims. Programs shouldn't overstate evidence. 'We served 5,000 customers and survey data shows improved food access' is honest. 'We reduced diabetes by 20%' without rigorous evidence is not.

The Cost of Measurement

Measurement isn't free. Funders should consider whether to fund evaluation specifically.

Basic tracking requires POS systems and modest staff time. Perhaps 5 to 10 percent of the program cost.

Customer surveys require design, administration, and analysis. This may be a few thousand to $20,000+ depending on rigor and sophistication.

Health outcomes research requires partnerships, data infrastructure, and possibly research staff. $50,000 to $200,000+ for meaningful studies.

Funders seeking rigorous impact evidence should budget for it explicitly rather than expecting it to be covered as part of program overhead.

For more on funding mobile markets, see: Funding Mobile Markets at Scale.