A Mobile Phone Based Pilot Intervention to Prevent Obesity in Latino Preschool Children
Phase: NA
Conditions: Childhood Obesity, Parenting, Mobile Phone Use
Sponsor: University of California, Los Angeles

 
 
 
 
 
 
 
NCT04261985   Unique Protocol ID: 1R21HD096298-01A1    
 
Secondary IDs: 1R21HD096298-01A1 
A Mobile Phone Based Pilot Intervention to Prevent Obesity in Latino Preschool 
Children 
 
February 17, 2022 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
Title: A mobile phone pilot intervention to prevent obesity in Latino preschool children 
 
Conditions:  
Childhood obesity interventions 
Mobile Health 
Latino populations 
 
Eligibility Criteria: 
 
Eligibility criteria will include an adult female or male caregiver who(1) self-identifies as an individual of Latino 
descent; (2) has a 2- to 5-year-old child/grandchild (where the relationship does not have to be biological but 
caregiveis a legal guardian); (3) lives with child or grandchild or cares for child/grandchild at least 20 hours per 
week; speaks Spanish or English; (4) is fluent in English or Spanish; (5) owns a mobile smart phone; (6) is able 
and willing to receive and interact with text messages on parenting, dietary, and physical activity strategies for 
young children (focus group Aim1); or (7) has the ability and willingness to participate in a 4-week mHealth 
intervention (Specific Aim2) and complete baseline, 1-month, and 6-month post-baseline measurement 
protocols. The ability to participate will be determined by using of a Subject Comprehension and Participation 
Assessment Tool. Families will be excluded if the child has a failure to thrive diagnosis or medical conditions 
related to overweight status such as Prader-Willi Syndrome. 
 
Age Limit:  
Minimum age 2 yrs  
Maximum no limit (N/A) 
 
PROTOCOL SYNOPSIS 
Summary 
The study objective is to pilot a stand-alone 4-week mobile phone intervention with Latino mothers, fathers, 
and grandparents, geared at building caregiver strategies to support evidence-based and age appropriate 
dietary, media-viewing, and physical activity practices among 2- to 5-year old children in order to resolve key 
challenges of traditional in-person pediatric obesity interventions (e.g. transportation, time), and also leverage 
important determinants of Latino health (e.g. familism, language). The primary and secondary endpoints are 
reached when all family cohorts complete their 6-month post-baseline data collection procedures. The study 
population is biological or adoptive mothers, fathers, and grandmothers of 2-to-5-year old Latino children living 
in Los Angeles, California without failure to thrive diagnosis or medical complications associated with their 
weight status such as Prader-Willi Syndrome 
A prospective randomized pilot study will be completed to assess acceptability, feasibility, and 
preliminary effect sizes on children’s weight-related behaviors and BMI z-scores at 6 months post-intervention, 
in preparation for a larger randomized trial to evaluate the intervention’s efficacy. The intervention will deliver 4 
interactive texts every week for one month to Latino caregivers of 2 to 5-year old children and 2-months of 
mobile phone “booster” doses that incorporate behavioral change techniques using a group strategy, a 
cornerstone of many effective in-person parent-focused pediatric obesity interventions. The study will first use 
qualitative methods to maximize the acceptability and usability of the existing mobile phone group learning 
strategies with a small group of Latino mothers, fathers, and grandparents. A 4-week mobile phone pilot 
intervention will then be completed with 66 caregiver-child dyads recruited from two WIC sites in East Los 
Angeles. Eligible caregiver-child dyads will be randomly assigned into the 4-week mobile phone intervention 
condition or the comparison condition, in which caregivers receive usual WIC services. Acceptability and 
feasibility outcomes will include: (1) the number of families needed to be screened per month; (2) attrition rates 
of a randomized mobile phone intervention with Latino populations; (3) dose and exposure of texts; (4) 
frequency of sharing/replying to texts by caregiver-type; (5) number of completed baseline and follow-up data; 
and (6) family-centeredness of the intervention. Pre- and post- intervention data will be collected at baseline, 1-
month, and 6-months after the intervention begins in order to estimate preliminary effect sizes and standard 
deviations associated with child dietary, physical activity, and media viewing practices and BMI scores. 
Mediators of the intervention will include measures of caregiver self-efficacy, caregiver feeding practices, and 
group support. The pilot study will provide the acceptability, feasibility, and preliminary data on child weigh-

related behaviors and BMI to develop an R01 proposal to test the intervention’s effectiveness via a large 
randomized controlled trial. 
 
Recruitment and Retention  
The proposed research studies will include focus groups to maximize acceptability and usability of a 4-
week childhood obesity mHealth intervention, followed by a pilot intervention research study to assess 
feasibility and preliminary outcomes of the 4-week mHealth intervention. The intervention’s focus on weight-
related behaviors during early childhood, requires the involvement and participation of child caregivers as the 
agents of change for child weight-related behaviors. The proposed research activities will, therefore, target 
mothers, fathers, grandmothers, and young children (2-5 years old). 
Study participants (mothers, fathers, and grandmothers) will be recruited using recruitment fliers and 
learn about the study by making contact with study investigators. All participants will provide written informed 
consent to participate in the study. To ensure that potential participants understand the study and the activities 
he/she will be asked to complete, we will use a Subject Comprehension and Participation Assessment Tool to 
assist in this process. Children’s assent or consent will not be obtained due to their young age (2-5 years old), 
although they may opt out. During consent procedures, participants will be given both written and verbal (in 
Spanish and English) information about the study to address low-literacy levels or limited English proficiency. 
Only legal guardians of a child will provide consent for the study, and non-legal guardians will excluded. 
Participants will be told and given information relating to all the potential risks of study involvement, including 
the potential for loss of privacy and the ethical obligation of researchers to report observed neglectful or 
abusive behaviors. All protocols for recruitment and informed consent will be vetted with our community 
partner, WIC, and included in our UCLA IRB application. 
Bilingual and bi-cultural research assistants will be trained and supervised by the research team (PI 
and Co-Is) and will be responsible for recruiting, screening, and consenting potential participants. We will 
propose distributing recruitment flyers explaining the study as families visit WIC centers. These recruitment 
flyers will be made available in English and Spanish and written at a 6th-grade reading level to ensure the 
information about the research activities are clear and understandable. A mother, father, or grandmother who 
cares for a child who is between the ages of 2 – 5 years old who expresses an interest in the study, will be 
instructed in the flyer to contact project staff, who will explain the study and invite the families to participate in 
the study. If introductory letters are not found to be effective for recruitment, we will recruit potential participants 
in person. 
For the focus group study (Specific Aim1) each caregiver, will be asked to complete one focus group 
session. Monetary incentives for participation will be comparable to amounts used in other research activities 
in the community, a $25 gift certificate for focus group participation. For the mHealth pilot intervention activities, 
mothers, fathers, and grandmothers will be asked to participate in a 4-week mobile phone intervention to build 
caregiver knowledge and skills related to healthy weight-behaviors for young children (Specific Aim 2). We will 
use similar recruiting strategies used for Specific Aim1 where potential parents will be recruited from 
community centers. Recruitment strategies will have a goal of enrolling equal numbers of mothers, fathers, and 
grandmothers. If recruitment flyers to encourage study participation do not yield the number of required 
participants, we may recruit participants’ in-person at WIC centers waiting rooms. Monetary incentives for all 
data collection points will be provided to retain participants in the study. We will use amounts comparable to 
other research activities in the community, a $25 gift card for each data collection point. In addition, if follow-up 
measurement appointments at the 6-month data collection points are low we may also explore a higher 
incentive amount to minimize attrition ($35).  
 
DATA and SAFETY MONITORING PLAN 
Data Safeguarding. 
The qualitative and quantitative research methods of the proposed studies will not involve the collection 
of biological samples or the use of drugs. The data collection activities of the proposed studies all constitute 
minimal-risk procedures. As such, there is no need to convene a formal data safety monitoring board but the 
study will include a Safety Officer. The PI, Dr. Guerrero, and the Safety Officer will have ultimate responsibility 
for data safeguarding. Dr. Guerrero will be responsible for day-to-day oversight of the data collection and data 
management, training the data collection team in data safeguarding techniques, and oversight of all staff who 
handle participant-identifying computer files, surveys, tracking forms, and other identifiable data. All research 
assistants and staff involved in data collection or handling of data, will receive training that addresses data 
safeguarding and confidentiality, and will sign confidentiality agreements. Raw data in need of safeguarding 

will include files generated to link identifying information with ID numbers and consent forms that will include 
participant name and unique ID. These raw data files will be stored in separate secure locations (encrypted 
data file on a password-protected desktop within my locked office and locked file cabinets within my locked 
office). The master code list and all raw data files will be destroyed once all data collection is completed and 
analyzed. 
 
Monitoring and Processes for Adverse Events.  
We do not expect that participants will experience adverse events. Although unlikely, if during our 
research studies with family caregivers we observe neglect, abuse, or a situation that is otherwise dangerous 
for children, we would ethically have to report such an observation to a higher authority such as Child 
Protective Services. For any other adverse event, staff will inform the Principal Investigator who will also 
communicate the adverse event to the study Safety Officer and then appropriate services and authorities (e.g. 
police, medical services, UCLA Office of the Human Research Protection Program) and request assistance. In 
all instances of adverse events, an Adverse Events incident report will be written and submitted to the UCLA 
Office of the Human Research Protection Program by the Principal Investigator. In addition, the funding agency 
and appropriate authority/ies will also be informed by the Principal Investigator. All phases of the study will be 
reviewed by the UCLA Office of the Human Research Protection Program. 
 
Analysis Plan 
Data Analysis Aim 1  
Focus groups will be professionally transcribed and translated. The PI and Co-Is, Drs. Ayala and Ramirez, will 
independently synthesize and organize the qualitative data into the a priori domains of acceptability and 
usability mentioned above, and identify any emergent themes. The PI and Co-Is will then meet to iteratively 
discuss and resolve differences by consensus. Focus groups will be used to analyze the following domains 
related to acceptability and usability: (1) identify preferred linguistic and culturally appropriate terms and 
images; (2) acceptability of sharing text, pictures, videos, and audio to support group learning; (3) preferred 
strategies for learning; (4) ease of using interactive texts; and (5) ease of completing interactive tasks. 
Data Analysis Aim 2.   
     Acceptability and feasibility will be analyzed using scores on the adapted HRSA MCHB Family-Centered 
Care items and the implementation and evaluation framework measures. Feasibility indicators will be 
evaluated against a priori criteria from the literature,63,66,67 providing a roadmap to evaluate “success” and 
whether to move forward with an R01 randomized clinical trial. Analyses of data from measures of children’s 
weight-related behaviors and BMI, as well as care-giver data will be done using Stata 15.0 software. Means 
and frequencies of outcome variables will be done for both the intervention and control group. T-tests and chi-
square tests will evaluate for group differences on baseline characteristics. Mixed effects linear regression 
models will be used to analyze the intervention’s effect on the outcomes of child behaviors and BMI score over 
time (baseline, 1- and 6-month post-baseline). These models will include intervention status, baseline dietary, 
physical activity, media-viewing behaviors, and BMI score, and selected covariates given the sample size. 
Furthermore, caregiver feeding practices and acculturation will be evaluated as potential moderators of 
intervention effects on child outcomes. Group Cohesion will be analyzed using scores on the adapted Physical 
Activity Group Environment Questionnaire60  and analyzing participant shared content using Linguistic Inquiry 
and Word Count software and theme taxonomies as used in other online support group studies64,65 These 
variables, will be examined to evaluate the extent to which they function as potential mediators of child BMI 
outcomes.