Developing components of an integrated mHealth dietary intervention for Mexican immigrant farmworkers: feasibility study of a food photography protocol for dietary assessment. (Preprint)

Abstract

Rural/urban disparities in access to health services and burden of diet-related non-communicable diseases (DR-NCD) are wider among Mexican immigrant farmworkers (MIFW) due to work demands, social and geographical isolation, literacy issues, and limited access to culturally- and language-competent health services. Although mHealth tools have the potential to overcome structural barriers to health services access, efficacious mHealth interventions to promote healthy eating have not considered issues of low literacy/health literacy, and food preferences/norms in the MIFW population. To address this gap, we conducted a series of preliminary studies among MIFW with the long-term goal of developing a culture- and literacy- specific smartphone application integrating dietary assessment through food photography, diet analyses, and a non-text-based dietary intervention. Here we report on the feasibility of a food photography protocol for dietary assessment among MIFW women.

To examine adherence and reactivity to a 14-day food photography dietary assessment protocol in which MIFW women were instructed to take photos of all foods and beverages consumed using a smartphone camera application.

We developed a secure smartphone application with an intuitive graphical user interface to collect food images. Adult MIFW women were recruited and oriented to the food photography protocol. Adherence and reactivity were examined by calculating the mean number of food photos/day, differences between first and second week, and between weekdays and weekends. Three days of food photos were compared to three 24-hour dietary recalls to further characterize adherence by type of foods and meal type.

Sixteen Mexican farmworker women took a total of 1,475 photos in 14 days, with a mean of 6.6 photos/day per participant (standard deviation [SD] 2.3). On average participants took one less photo/day in week 2 (mean= 6.1, SD 2.6) compared to week 1 (mean= 7.1, SD 2.5) (P=.03) and 0.6 photos less per day on weekdays versus weekends (mean= 6.4, SD 2.5 vs. week 2 mean= 7, SD 2.7; P=.5). Of individual food items, 352 foods and beverages in the recalls matched foods in the photos (71%). Of all missing food items (138) and meals (36) in the photos, beverages (54%) and tortillas (11%), snacks (44%) and dinners (28%) were the most frequently missed. Most of the meals not photographed (75%) were in the second week of the protocol.

Dietary assessment through food photography is feasible among MIFW women. For future protocols, substantive adjustments to reduce the frequency of missing foods and meals will be introduced such as a shorter assessment period and the use of automated text message prompts. Our preliminary studies are a step in the right direction to extend the benefits of mHealth technologies to a hard-to-reach group and contribute to the prevention and control of DR-NCD.