South Texas Early Prevention Studies - PreK
Phase: NA
Conditions: Childhood Obesity
Sponsor: University of Texas Rio Grande Valley

South Texas Early Prevention Studies PreK 
Study Design and Protocol 
September 28, 2018 
 
 

 
Study Design and Participants 
The STEPS-PreK4 was a CRT where preschools, embedded within elementary 
schools, were the unit of randomization, intervention, and analysis. The study was 
designed for two years of intervention (pre-kinder to kindergarten) and four data 
collection periods (fall 2018, spring 2019, fall 2019, and spring 2020). Due to the 
COVID-19 pandemic the study was stopped prematurely and only results from the first 
three periods will be presented.  
The two school districts where the study was conducted are located along the Texas-
Mexico border in the county of Hidalgo. These school districts were selected because of 
the high poverty and health risk-factors levels.25 The preschools have two grade levels 
with children 3 and 4 years of age. The present study targeted preschools with children 
4 years of age. Demographics of the two school districts were similar, 99% Hispanic, 
92% economically disadvantaged, and 42% identified as English as a second language.  
 
Intervention 
The BN CHSP is a Texas Education Agency (TEA)-approved CSHP. This health 
program was first piloted in schools located in low-income neighborhoods where 
enrollment was predominantly Black and Latino children. For this reason, the curricula 
were given the name Bienestar/NEEMA. Bienestar and NEEMA mean well-being in 
Spanish and Swahili, respectively. TEA-approved CSHP aims is to control and 
prevent childhood obesity, youth-onset type 2 diabetes, and cardiovascular disease 
by providing instruction in health, nutrition, physical education, and chronic disease 
knowledge across several environments.   
The Social-Ecological Model guided the BN CSHP design. This theory postulates that 
health behaviors are molded by individual, interpersonal, and environmental 
interactions. Thus, BN CSHP encompasses curricula from preschool to eighth grade 
and is designed to target the four environments that influence children’s health 
behaviors: 1) Healthy Lifestyles Healthy Minds (Health), 2) Moving For Life (Physical 
Education), 3) Eat to Live (Child Nutrition/School Food Service), and 4) 
MyFamily/MiFamilia (Home). Table 1 shows the preschool health education 
components of both treatment arms. 
 
Measures 
Household characteristics. Family Demographic and Household Health Characteristic 
questionnaires were sent to parents/guardians through 4 modes: online, face-to-face, 
school parent liaisons, and children. English and Spanish questionnaires collected 
information on age, gender, race/ethnicity, educational attainment, household income, 
persons living per household, physical activity, sedentary lifestyles, and family (1st and 
2nd degree) history of hypertension and diabetes. 
PACER Fitness Test. The PACER fitness test is a multistage shuttle run designed to 
measure CRF.26 The objective of the PACER is to run as long as possible while keeping 
a specified pace. Children run back and forth across a 20-meter course at a tempo that 
gets faster each minute paced by an audio signal. For this study, the PACER test was 

adapted for preschool children by adjusting the course to a 15-meter distance and using 
a 20-meter cadence. The test begins at a slow pace and each minute the pace 
increases. Beeps on the soundtrack indicate when a student should reach one end of 
the course where they stop and wait for the next beep. Children continue running until 
the pace can no longer be sustained for two laps. As soon as children stop running, 
their number of laps are recorded. 
 
Sample Size Calculation 
The sample size for the primary endpoint, obesity prevalence, assumed a 5% obesity 
rate decrease in the intervention compared to control group, a SD of 1.4, an intra-cluster 
correlation coefficient of 0.01, 70% response rate, and an attrition rate of 16 percent. 
[source: LJ ISD, PSJA ISD] A total of 28 preschools (clusters) with a mean cluster size 
of 49 children per school was estimated to detect the effect size with 80% power at a 
significant level of α = 0.05. The calculated sample size was enough for a difference of 
at least 4.5 laps between treatments (secondary outcome) and the statistical power was 
82% for alpha 0.05 with sample size of 40 children per cluster.