Location Initiated Individualized Texts for African American Adolescent Health (LIITA3H)

Project start and end date: December 2017-December 2019

The obesity epidemic in the US has disproportionately affected African American (AA) adolescents who have a prevalence of obesity that is almost 50% higher than that of Caucasian teens. This higher prevalence is due in part to greater exposure to, and higher consumption of, fast food and calorie dense foods among minority populations than their majority peers. Finding effective ways to address dietary habits affecting childhood obesity in general and in African American adolescents particularly is vital in order to avert the magnitude of obesity-related illnesses and the associated costs that are likely to cloud the future of American children. 

Youth consume a significant proportion of their calories away from home (e.g., fast food restaurants, convenience stores). A significant number of AA adolescents live in low-income communities with a disproportionally high prevalence of surrounding fast food restaurants and convenience stores. Better ways to help AA adolescents make healthy choices in these obesogenic environments is critical to reduce the disparities present in childhood obesity.


  • Aim 1: To optimize the LIITA3H app by a) including newly available technology to automatically identify a larger number of fast food restaurants (FFR), and b) incorporating user input to enhance the design of the app.
  • Approach: GPS monitoring will be linked to a database of coordinates for fast food restaurants, to facilitate the identification of users’ presence in a restaurant.  In addition, input from the target population will be elicited via focus groups and from an adolescent advisory board and used to enhance the user interface of the app. 
  • Aim 2: To pilot test the LIITA3H app, to assess whether its use, over 6 months, is associated with the two main outcomes of: a) fewer calories purchased from FFR and b) fewer visits made to FFR. 
  • Approach: The pilot will consist of 3 arms (an intervention group, and 2 control groups) to assess:
    • Calories purchased from FFR: Photos of purchases submitted by users will be cross-referenced with a fast food nutrition database to calculate calories. The mean number of calories purchased will be compared for the intervention group 1 (with the full app that identifies location, allows photo documentation and has point of purchase motivational prompts) vs. the control group 2 with a version of the app that will ask users to photograph their foods but will not provide the motivational messages.
    • Visits to FFR:  Number of visits to FFR will be automatically tallied by the app using GPS to link users’ location to restaurant coordinates. Comparisons will be made between the intervention group 1, the control group 2, and control group 3 with a version of the app that only tracks location (but no photos or prompts). Secondary Analysis – The impact of frequency of use of the application and participant characteristics (e.g., BMI and ethnic identity), on the main outcomes of calories purchased and visits to FFR, will be explored.

Research Topics & Methods:
This study will determine potential efficacy in a high-risk population. LIITA3H will provide a convenient means to influence point of purchase choices and thereby impact obesity and its comorbidities, which are a burden for individuals and society. Linking messaging to location in a mobile app, that may be adapted to address other conditions and populations, offers the potential to reduce a wide range of health disparities.

This project is funded through a National Institute of Child Health and Human Development (NICHD) R21 grant.

MEI Research Ltd.

For more information, please contact:
Associate Professor, Department of Pediatrics
NCRC Building 16, G028W
2800 Plymouth Road
Ann Arbor, MI 48109-2800


Project Manager:
Theresa Kowalski-Dobson, MPH

300 North Ingalls, Rm 6C09
Ann Arbor, MI 48109-5456

Phone: 734-232-2455
Fax: 734-232-1400
Email: tkowals@med.umich.edu