Finding healthy food with a phone: Evaluating promotion of a text message-based tool (Locarto) to locate fruit and vegetable vendors (Green Carts)

The NYC Green Cart program provides jobs and affordable fruits and vegetables to underserved communities through street vendor permits. A cell-phone accessible, internet-based geolocation tool, Locarto (locarto.com) was developed to drive customers towards Green Carts. Vendors update their location using text messages; consumers locate vendors via text messages or the internet. In early 2012, Locarto was promoted as part of cooking demonstrations in Montefiore clinic waiting rooms. Promotion of Locarto was evaluated by compiling daily unique user counts on the text-message service and website. An interrupted time series analysis compared daily counts of (i) text messages and (ii) website visitors (a) before, (b) during, and (c) after the intervention to assess any differences attributable to the intervention. Compared to baseline, we expect to find an increase in the daily counts during our intervention, followed by a gradual decrease after the outreach is withdrawn. Interrupted time series analysis is an important tool in assessing the promotion of a new text message-based geolocation tool for locating healthy food in underserved communities.