A Cluster-Randomized Trial of a Mobile Produce Market Program in 12 Communities in North Carolina: Program Development, Methods, and Baseline Characteristics

Using implementation mapping to refine strategies to improve implementation of an evidence-based mobile market intervention: a study protocol

Objectives

The Veggie Van model is a mobile market model that is efficacious in increasing fruit and vegetable consumption for lower-income participants. The model is currently being evaluated for its effectiveness in a multi-state trial. Preliminary implementation data, collected through process measures surveys and implementation interviews, indicate that there are several barriers to implementation among partner organizations and implementation fidelity to the Veggie Van model was low. Consideration and planning for implementation ought to occur early and often throughout the research process order to ensure Veggie Van model effectiveness. This paper describes the step-by-step process for creating strategies to enhance implementation of Veggie Van model components.

Methods

Implementation mapping is a systematic process to develop implementation strategies through engagement with key stakeholders. We conducted a series of interviews (n = 31 representatives) with partner organizations (n = 8) to identify facilitators and barriers to Veggie Van model implementation. We then applied interview findings to an Implementation Mapping process to develop theory and practice-driven strategies to be integrated into existing implementation tools and technical assistance.

Results

We identified implementation outcomes (e.g., staff implement the Veggie Van model component of nutrition education with fidelity) and performance objectives (e.g., offer nutrition education, in the form of food lessons and/or food demonstrations, at least bi-weekly) to achieve them. We conducted a secondary qualitative analysis of the findings from implementation interviews with partner organizations to identify behavioral determinants (e.g., attitudinal beliefs, social support) which were combined with the performance objectives to generate change objectives (e.g., view the Veggie Van model as advantageous to an organization and communities served). To achieve the change objectives, we developed implementation strategies that would be integrated into existing Veggie Van training resources including an online toolkit, webinars and trainings, an annual mobile market conference, and technical assistance.

Conclusion

The development of theory and practice-driven implementation strategies will enable us to improve our implementation tools, thereby improving fidelity to the Veggie Van model among organizations and increasing the likelihood of its effectiveness. Detailing the design of a multifaceted implementation strategy using Implementation Mapping also provides a model to design similar strategies for other community-based interventions.

A Novel Process to Recruit and Select Community Partners for a Hybrid Implementation-Effectiveness Study

BACKGROUND

Creating strong partnerships with community organizations is essential to test implementation of evidence-based interventions. However, partners are often chosen based on convenience rather than capacity or diversity. Streamlined processes are needed to identify qualified, diverse, and invested partners to conduct community-based research.

OBJECTIVES

There is a gap in the literature on effective and efficient processes for recruiting partners. This paper aims to fill that gap by describing a novel approach for identifying a diverse group of community organizations to participate in research.

METHODS

We used a Request for Partners (RFP) approach to recruit partners to participate in a hybrid implementation-effectiveness study of the Veggie Van mobile market model. The process included formative work to inform RFP development, creation of an external advisory committee, an intent-to-apply round, a full application round, and an inperson training and selection process. Data was collected to characterize applicant size, location, and experience; pre-post surveys were conducted to understand the training's utility.

RESULTS

We received 59 intent-to-apply submissions and invited 28 organizations to apply: 17 submitted applications and 12 organizations were chosen as finalists. The process took approximately 8 months to recruit 9 organizations and 32 community sites across 5 states and increased understanding of the intervention and partner responsibilities.

CONCLUSIONS

An RFP process is familiar to many community organizations that compete for grant funding but may not have prior research experience. This process streamlined recruitment timelines, increased diversity, and cultivated community among organizations. It may also improve research transparency, study completion, and intervention fidelity.

Impacts of the COVID-19 Pandemic on Mobile Produce Market Operations: Adaptations, Barriers, and Future Directions for Increasing Food Access

BACKGROUND

Mobile produce markets were increasingly recognized as an effective and accepted approach to improving access to fruits and vegetables in lower-income and at-risk communities during the first year of the COVID-19 pandemic in the United States. This study provides insights into how mobile market operations were impacted by, and evolved in response to, challenges posed by the pandemic.

METHODS

A survey evaluating impacts of the pandemic on mobile markets was distributed to a database of mobile market operators in the United States. Respondents were asked to describe impacts to their mobile market's operations, and what adaptations were needed to continue to effectively serve their communities during 2020.

RESULTS

Surveys representing 48 unique mobile markets were collected from March to July 2021. Of the respondents, 63% reported an increase in demand for mobile market services from community members. Furthermore, 65% increased the amount of produce they distributed in 2020 as compared to 2019, often through adopting low or no-cost models or participating in pandemic government programs.

DISCUSSION

Emergency adaptations employed by mobile markets can inform long-term operational modifications for not only mobile markets, but also other food access programs, beyond the COVID-19 pandemic.

An Investigation of Social Ecological Barriers to and Facilitators of WIC Farmers Market Nutrition Program Voucher Redemption

In the United States, many communities lack sufficient access to fresh produce. To improve access to fresh fruits and vegetables, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) provides eligible participants vouchers through the Farmers Market Nutrition Program (FMNP) that can be redeemed directly from farmers at markets or farm stands. However, FMNP voucher redemption rates in New Jersey remain lower than those in neighboring states. This article used the social ecological model to examine differences between FMNP participants who redeem vouchers (Redeemers) and those who do not (non-Redeemers) in the areas of: produce procurement practices and consumption frequency, and barriers to and facilitators of FMNP voucher redemption. This cross-sectional study included WIC FMNP participants (N = 329) in northern New Jersey, USA. Analyses were conducted using descriptive statistics, independent sample t-tests, and one-way ANOVA. Compared to Redeemers, non-Redeemers consumed fewer average daily vegetable servings, were more likely to shop at small grocery/corner stores, and encountered significant barriers to FMNP redemption, e.g., difficulty finding time to redeem vouchers.

Using common practices to establish a framework for mobile produce markets in the United States

Access to affordable fruit and vegetables (F&V) remains a challenge within underserved communities across the United States. Mobile produce markets (mobile markets) are a well-accepted and effective strategy for increasing F&V consumption in these communities. Mobile market organizations share similar missions that focus on food, health, and empowerment, participate in incentive programs, offer nutrition education, utilize grassroots-based marketing strategies, prioritize local produce, and sell competitively priced produce through a market style. While mobile markets have become increasingly prevalent, models vary widely. Establishing standardized practices is essential for ensuring the effectiveness and sustainability of this important food access program. This research seeks to identify common practices of established mobile markets and describe the resources they rely on.

Participant Perceptions of a Free Fresh Produce Market at a Health Center

OBJECTIVE

To examine participant perceptions of a free, monthly produce market at a health center in Massachusetts.

DESIGN

Participants were recruited at a produce market between June 2019 and January 2020 and engaged in a 30-65-minute focus group (n = 3 English language; n = 2 Spanish; n = 2 Arabic) conducted by trained facilitators using a semistructured guide.

PARTICIPANTS

Adults (n = 49) who had attended the market at least twice in the previous 6 months.

MAIN OUTCOME MEASURES

Participant-reported facilitators, barriers, perceived benefits, and opportunities for improvement.

ANALYSIS

Conventional content analysis.

RESULTS

Reported facilitators included accessibility (eg, convenient location and timing), program experience (eg, positive volunteer interactions), and characteristics of goods and services (eg, acceptable variety of produce). Barriers fell under similar themes and included transportation challenges, poor weather, and insufficient quantity of produce for larger households. Participants perceived the market as improving diet and finances and offered suggestions for improvement: distributing nonproduce foods (eg, meat) or nonfood items (eg, toiletries) and augmenting existing initiatives aimed to help attendees make use of the produce (eg, handing out recipe cards).

CONCLUSIONS AND IMPLICATIONS

The produce market was widely accepted, and targeted areas for improvement were identified. Findings may improve existing and future charitable produce markets among diverse populations.

Dietary policies and programs in the United States: A narrative review

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School-based and youth targeted programs and policies were most frequently studied.

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Research has rather neglected older adult, Asian, Native Hawaiian and American Indian populations.

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Despite existing research indicating effectiveness, faith-based were understudied.

Prior reviews describing approach, methodological quality and effectiveness of dietary policies and programs may be limited in use for practitioners seeking to introduce innovative programming, or academic researchers hoping to understand and address gaps in the current literature. This review is novel, assessing the “where, who, and in whom” of dietary policies and programs research in the United States over the past decade – with results intended to serve as a practical guide and foundation for innovation. This study was conducted from October 2018 to March 2019. Papers were selected through a tailored search strategy on PubMed as well as citation searches, to identify grey literature. A total of 489 papers were relevant to our research objective. The largest proportion of papers described school-based strategies (31%) or included economic incentives (19%). In papers that specified demographics, the study populations most often included children, adults and adolescents (54%, 46%, and 42% respectively); and White, Black and Hispanic populations (77%, 76% and 70%, respectively). Results highlight opportunities for future research within workplace and faith-based settings, among racial/ethnic minorities, and older adults.

Cluster randomized controlled trial of a mobile market intervention to increase fruit and vegetable intake among adults in lower-income communities in North Carolina

Background

Poorer diets and subsequent higher rates of chronic disease among lower-income individuals may be partially attributed to reduced access to fresh fruits and vegetables (F&V) and other healthy foods. Mobile markets are an increasingly popular method for providing access to F&V in underserved communities, but evaluation efforts are limited. The purpose of this study was to determine the impact of Veggie Van (VV), a mobile produce market, on F&V intake in lower-income communities using a group randomized controlled trial.

Methods

VV is a mobile produce market that sells reduced-cost locally grown produce and offers nutrition and cooking education. We recruited 12 sites in lower-income communities in North Carolina (USA) to host VV, randomizing them to receive VV immediately (intervention) or after the 6-month study period (delayed intervention control). Participants at each site completed baseline and follow-up surveys including F&V intake, perceived access to fresh F&V and self-efficacy for purchasing, preparing and eating F&V. We used multiple linear regression to calculate adjusted differences in outcomes while controlling for baseline values, education and clustering within site.

Results

Among 142 participants who completed the follow-up, baseline F&V intake was 3.48 cups/day for control and 3.33 for intervention. At follow-up, adjusted change in F&V consumption was 0.95 cups/day greater for intervention participants (p = 0.005), but was attenuated to 0.51 cups per day (p = 0.11) after removing extreme values. VV customers increased their F&V consumption by 0.41 cups/day (n = 30) compared to a 0.25 cups/day decrease for 111 non-customers (p = 0.04). Intervention participants did not show significant improvements in perceived access to fresh F&V, but increased their self-efficacy for working more F&V into snacks (p = 0.02), making up a vegetable dish with what they had on hand (p = 0.03), and cooking vegetables in a way that is appealing to their family (p = 0.048).

Conclusions

Mobile markets may help improve F&V intake in lower-income communities.

Trial registration

Clinicaltrials.gov ID# NCT03026608 retrospectively registered January 2, 2017.

Electronic supplementary material

The online version of this article (10.1186/s12966-017-0637-1) contains supplementary material, which is available to authorized users.