Engaging Navajo Elementary Schools in Randomized Controlled Trial of Yeego! Healthy Eating & Gardening
Phase: NA
Conditions: Dietary Habits, Health Behavior, Eating Behavior
Sponsor: Fred Hutchinson Cancer Center

Engaging Navajo Elementary Schools in Randomized Controlled Trial of Yéego! Healthy Eating & 
Gardening 
 
Study Protocol 
 
 
 
 
 
 
NCT03778021 
Document IRB approved 12/27/2020 
 
Investigators: 
PI: Shirley A.A. Beresford, PhD (UW) 
PI: Kevin Lombard, PhD (NMSU) 
Co-I: India Ornelas, PhD (UW) 
Co-I Mark Bauer (Project Director at Diné College) 
Co-I Geraldine Garrity (Education scientist at Diné College)  
 
 
FHCRC Staff: 
Project Manager, Sonia Bishop 
Staff Scientist, Eileen Rillamas-Sun 
Research Assistant, Heather Wilcox (UW) 
 
NMSU Staff: 
Brandon Felix, Field Coordinator/Interventionist at Shiprock  
Jenna Cope, Nutrition Curriculum Interventionist at Shiprock (Indian Health Services) 
Lydia Kim, Nutrition Curriculum Interventionist at Shiprock (Indian Health Services) 
Keona Manuelito, NMSU Summer Field Intern 
Katlynn Gilmore, NMSU Summer Field Intern 
 
 
Diné College Staff: 
Linda Garcia, Assessment coordinator 
Felix Nez, Garden Curriculum Interventionist at Tsaile  
Filiberto Vecenti, Nutrition Curriculum Interventionist at Tsaile 
Morgan Farley, Data Collector 
Amber Begay, Data Collector 
Debbie Higgs, Data Collector 
 
 
 
 
 
 

Table of Contents 
 
I. 
Rationale and Background  
II. 
Specific Aims 
III. 
Research Approach 
A. Overview and Design 
B. Research Team Strengths and Roles 
C. Study Sites 
D. School Engagement and Recruitment 
IV. 
Intervention and Assessment 
A. Yéego! Healthy Eating and Gardening Intervention 
B. Data Collection/Assessment   
C. Outcome Measures 
D. Process Measures: Recruitment, Retention and Fidelity 
E. Analysis Plan 
V. 
List of Study Documents  
A. Parent Consent 
B. Child Assent 
C. Baseline Questionnaire 
VI. 
References  
  
 
 

I. 
RATIONALE AND BACKGROUND  
Navajo families are at increased risk for obesity, diabetes and cancer,3-5 in part due to low fruit and 
vegetable consumption. For children, these behaviors are greatly influenced by their school and home 
environments. Research has found that as availability and accessibility of fruits and vegetables increases, so 
does consumption. Furthermore, recent studies of effective child obesity prevention programs, have shown 
that school-based interventions that incorporate nutrition education and gardening can increase both children 
and their parents’ healthy eating and gardening behaviors.21-23 Our study aims to increase consumption of 
fruits and vegetables, through a curriculum focused on increasing knowledge and self-efficacy to grow and 
prepare healthy foods, as well as increasing their availability through a school garden.  
Poor availability and accessibility of fruits/vegetables is a significant barrier to healthy eating in Navajo 
communities due their high cost, poor quality, and long distances to reach supermarkets that stock fresh 
produce.6 Our previous research suggests that the schools in this area provide an opportunity to increase 
engagement of both children and their parents in health promotion interventions, including targeting behaviors 
that, unchecked, lead to obesity early in the lifespan. The impact of this study on knowledge, self-efficacy and 
behavior around healthy eating will be significant for both the participating school children and their families. 
Establishing health behaviors, including healthy eating choices, in childhood has been associated with positive 
health in adulthood and the potential to have a long-term/sustainable impact on health.24,25 Children’s 
behaviors can also influence adult family member behaviors. Many intervention studies around diet and 
physical activity have focused on schoolchildren for this reason.26,27  
Incorporating cultural traditions in interventions is vital to sustaining behavioral change. Maintaining 
language and cultural traditions has been recognized as being important for both a strong ethnic identity and 
health in racial/ethnic minority populations in the United States.28,29 Traditional growing practices, augmented 
with modern methods of irrigation, and eating traditional foods have been associated with positive health in 
American Indian populations.1,30,31 Our previous studies have identified a strong interest in promoting Diné 
language and cultural practices, and school-based gardens have the potential to be effective because they 
draw on the same cultural traditions and strengths of Navajo communities and intergenerational transfer of 
knowledge.32,17 This model is consistent with other school-based gardens occurring in Native American 
communities, including the Navajo Nation, and why Navajo adults believe strongly in the importance of 
educating youth on Navajo farming heritage.33 The curriculum we have designed and are implementing at a 
Navajo elementary charter school in Shiprock incorporates elements of Diné philosophy, Navajo language and 
culture and holds promise in making a significant health impact in the community. 
 
II. 
SPECIFIC AIMS 
The Navajo Nation (Diné people) has identified gardening and healthy eating as priorities, demonstrated in 
the recent Diné College Food Sovereignty report, by the junk food and soda tax instituted in 2015, and in the 
advocacy by tribal leaders for expanding gardens across the Nation.1,2 Navajo families are at increased risk for 
obesity, diabetes and cancer in part due to low fruit and vegetable consumption.3-6 Over the past nine years, 
we have worked with community leaders from the Navajo Nation to research effective ways to promote 
gardening and healthy eating, and are now poised to estimate the efficacy of a school-based intervention to 
promote healthy eating and gardening in Navajo children. Previously, we have shown that gardening is a 
culturally appropriate intervention strategy for improving healthy eating in this population.7,8 Community 
members have shared with us the importance of family in shaping their health behaviors, and a desire to 
protect the health of the next generation by encouraging healthy eating habits. Therefore, we developed and 
piloted a school-based intervention to promote gardening and healthy eating among Navajo elementary school 
children. The “Yéego! Healthy Eating & Gardening” intervention was developed based on social cognitive 
theory, on previous school-based gardening interventions reported in the literature, 9 and our own formative 
work in Navajo communities. We collaborated with a Navajo elementary charter school in Shiprock, NM to 
develop an integrated curriculum and school-based garden incorporating Diné philosophy of thoughtful 
allocation of local and natural resources. The intervention aims to build students’ self-efficacy to grow and eat 
fruits and vegetables, as well as making other healthy food choices. While Navajo leaders have shown their 

commitment to health through adoption of policies to encourage healthy eating among Navajo children, we 
know that these policies must be paired with successful interventions that are rigorously evaluated to inform 
additional wellness policy within schools. These interventions and policies, when broadly implemented are 
expected to reduce the risk of being overweight in children, including Diné children, who are at higher risk for 
diabetes and for the more than 13 specific cancers linked to obesity. Note: We use Navajo and Diné 
interchangeably in this grant. 
In this study we will estimate changes in healthy eating and gardening behaviors associated with the 
intervention using a randomized controlled trial design, with the comparison arm receiving a delayed intervention 
in the following school year. Combining community engagement with rigorous design and analysis is a 
significant contribution of this study to the Cancer Health Disparities partnership. In parallel with implementing 
the randomized trial, we will actively maintain the collaborations with our charter Navajo school partners and 
with our longstanding collaborators in Shiprock, Tsaile and Crownpoint, by inviting them to be advisors and 
champions for the new trial. In particular, our specific aims are to: 
Aim 1. Engage and recruit Navajo elementary schools to participate in a randomized controlled trial of  
“Yéego! Healthy Eating & Gardening” intervention, an integrated healthy eating and gardening curriculum and 
school-based garden. This phase will include meetings with school leadership, parents and teachers and 
assessing eligibility. A formal protocol including a run-in period will ensure willingness and capacity to 
participate in the study for at least two years. 
Aim 2. Estimate the efficacy of the “Yéego! Healthy Eating & Gardening” intervention to increase healthy 
eating and gardening behaviors in Navajo elementary school children. The primary outcomes are child 
measures: a) tendency to choose vegetable and fruit items to eat; b) healthy eating score from a Navajo foods 
picture sort; c) gardening at home and d) self-efficacy to garden.  
We anticipate 4 to 6 schools will participate in the main study. We will also assess process outcomes, 
including: recruitment, retention and intervention fidelity, and secondary intervention effects on parent healthy 
eating and gardening behaviors. Assessments will be conducted in a sample of the elementary school children 
in grades 3 and 4 at each school and in one of their parents (or other adult caregiver in the household that is 
the index adult for analysis), at the beginning and the end of the first school year. We use a culturally 
appropriate tool that includes foods commonly eaten by Navajo people to measure food choices in both 
children and parents. Choosing fruit and vegetables to eat at meal times in children and gardening participation 
and self-efficacy in children will be assessed using instruments from other studies. Secondary outcomes 
include measures of child weight and of academic achievement, as well as parent measures of healthy eating 
and gardening. Analyses estimating the intervention effect will assess the differential change over the first 
school year between the two groups of schools, adjusting for school level clustering. After the follow-up 
evaluation, the delayed intervention group will receive the intervention. A final descriptive assessment will be 
included at the end of the second school year. Continued engagement and skill strengthening will occur 
through quarterly parent workshops. Attendance at these will be tracked. This proposal is timely as the Navajo 
Nation consider their policy on dietary and activity benchmarks for schools as part of a rounded curriculum. 
 
III. 
RESEARCH APPROACH 
A. 
Overview and Design 
The small randomized controlled trial of an intensive curriculum and school garden intervention will be 
implemented in elementary schools in two communities (Shiprock and Tsaile). The study will begin in year 1 
with a period of engagement and recruitment of schools in each community; with the goal of recruiting three 
schools in each community to start the run-in phase (see Figure 1). The run-in period will include time for 
greater engagement with the school community, an assessment of the potential garden site and an 
assessment of evaluation readiness. Depending on whether all three schools in the community qualify for the 
study at the end of run-in, or only two schools per community, we will randomize three or two schools to 
intervention or delayed intervention status in each community. We will have either two intervention schools and 
4 delayed intervention schools, or 2 intervention schools and 2 delayed intervention schools, depending on the 
run-in information. We will conduct baseline data collection (T1) at the beginning of the school year in Year 2 

with both children and parents. Students in the intervention group will receive the curriculum and school garden 
during that academic school year. At the end of the school year, we will conduct the T2 assessment in children 
and parents. The main evaluation period is between T1 and T2, and the statistical analysis methods refer to 
the T2 versus T1 change in outcome measures (healthy eating and gardening). After that, at the beginning of 
the next school year (Year 3), the delayed intervention schools will receive the intervention. During Year 3, we 
will also conduct quarterly community gardening workshops for adult family members in all schools. 
Attendance at these will be tracked. A final assessment (T3) will be conducted at the end of the second school 
year in all the randomized schools to describe behaviors in children and parents over time, using a quasi-
experimental design that estimates change in the delayed intervention group between T2 and T3, attributable 
in part to the delayed intervention. 
 
B. 
Research Team  
The research team includes investigators from NMSU, Fred Hutch and Diné College with complementary 
expertise in the development and evaluation community and school-based health behavior interventions, 
gardening, education, and community engagement. The team also includes staff and consultants with 
expertise in Navajo culture, farming and agriculture. The project will be led by Drs. Kevin Lombard, Associate 
Professor of Horticulture at NMSU and Director of the NMSU Agricultural Science Center (ASC) sited on the 
Navajo Nation land and Shirley Beresford, Full Member at the Fred Hutch and Professor of Epidemiology at 
UW. This study draws on the complementary strengths of all institutions and investigators involved.  
 
Fred Hutch 
Dr. Beresford’s role is to provide guidance on study design, dietary assessment and statistical inference, 
adhering to the most rigorous evaluation methods while honoring the community collaborative nature of this 
project. Because of her long history of cross-discipline collaboration, she is able to leverage some of the 
institutional strengths of the Fred Hutch, including cancer prevention randomized trials (group and individual 
level) and state of the art dietary assessment methodology and statistical expertise. Dr. Ornelas, an 
Associate Member at Fred Hutch and Associate Professor in Health Services at UW brings expertise in 
community engagement, working with American Indian populations, and designing and implementing health 
promotion interventions. Her role in the project is to provide guidance in each of these areas.  
 
 
New Mexico State University (NMSU) 
Dr. Lombard’s role is to provide guidance in gardening and horticultural issues, and to continue to foster 
and grow the already strong relationship with Navajo community partners. The relationships the NMSU 
ASC has with Navajo tribal leaders are essential for conducting community-engaged research in the region. 
Dr. Lombard and his team made up of both NMSU and Diné College scientific staff will be responsible for 
recruitment of participating elementary schools, assessment at three time points, implementation of the 
intervention and continued community engagement.  All data collection and intervention implementation work 
will be based at NMSU ASC and Diné College, with assistance provided by FHCRC investigators and staff.  
Dr. Lombard will assume responsibility for oversight of the Dine college staff as they contribute to the 
Figure 1: Study Design 

activities outlined above.    
 
Diné College 
Several investigators from Diné College bring expertise in education and health in Navajo communities 
(Mark Bauer, Professor Public Health; Kathryn Hartzell, science faculty in Public Health; Geraldine Garrity, 
Chair of the Diné Teacher Education Program and Interim Provost, Diné College). Dr. Bauer has conducted 
previous gardening and health promotion studies in Shiprock and Tsaile. Dr. Hartzell has experience in 
curriculum and instructional design and implementation. Dr. Garrity brings expertise in the Navajo 
language, culture and educational system. The intervention coordinators, TBD (based in Shiprock) and Felix 
Nez (based in Tsaile) are both Navajo and have a background in gardening education.  The investigators and 
staff will be paid by a subcontract through NMSU. 
 
Team Meetings 
Core investigators and research staff will have weekly team meetings by phone and video conference to 
make joint decisions about the study. In addition, Fred Hutch investigators and staff will travel semi-annually to 
the study sites to assist with study coordination.  
C. 
Study Sites 
Shiprock is situated at an important road junction (U.S. 499 and U.S. 64). It is home to several important 
Navajo institutions: the annual Northern Navajo Fair, a branch campus of Diné College, the Bureau of Indian 
Affairs, an Indian Health Service (IHS) hospital, a branch office of the Tri-State Agricultural Extension Service, 
a branch office of NMSU Cooperative Extension, and a branch office of the Navajo Special Diabetes Unit. 
According to 2010 Census estimates, the household population is 8,295 (52% female), with 2,706 housing 
units. More than 96% of the population is Navajo and about 64% of the population speaks Navajo at home. 
Also 37% of Shiprock residents live in poverty and about 45% under the age of 65 do not have health 
insurance, relying on IHS clinics for primary health care.43 There are significant areas of irrigated farmland due 
to Shiprock’s close proximity to the San Juan River. During the short growing season, common crops are 
alfalfa for animal grazing, along with corn and squashes. One full-service grocery store sells fruits and 
vegetables year-round. There are eight fast food restaurants in town. The closest major service center is 
Farmington, NM about 30 miles from Shiprock. 
Tsaile is home to one of the first tribally controlled higher educational institutions, Diné College. Founded in 
1968, the institution now operates in seven satellite locations across the Navajo reservation. Tsaile also 
houses its own land grant extension office as part of the 1994 land grant extension. According to 2010 Census, 
the household population is 1,198 (55% female), with 335 housing units. 44 More than 72% of the population is 
Navajo and about 50% of the population speaks Navajo at home. About 46% of Tsaile residents live in poverty, 
with a median age of 19. Occupations in the administrative, educational, and food service sectors make up the 
most available job opportunities. Diné College is the largest employer followed by the Tsaile public school and 
the satellite Indian Health Service clinic.45 Tsaile is about 25 miles from Chinle and 50 miles from Window Rock 
grocery stores and restaurants. Food purchases are mainly through gas stations, trading posts and roadside 
stands. There are no fast food restaurants in Tsaile due to the isolation and remoteness of the community, 
other economic ventures include livestock production, some farming, and arts and crafts.45 

D. 
School Engagement and Recruitment 
Our first aim is to engage and recruit elementary schools from two communities on the Navajo Nation for 
the randomized control trial of the Yéego! Healthy Eating & Gardening intervention. We recognize that 
personal interactions with key stakeholders is an essential part of community engagement. This will require the 
assistance of “key influential” in the school system, faculty educators at Diné College, and local residents who 
are Navajo members of our research team. Based on our previous experience in recruiting of organizations for 
group-randomized trials, we plan to implement the following steps to recruit and engage potential schools as 
research partners. In defining the population of schools from which to recruit, we note there are about 90 
elementary schools in the Navajo Division of Education system, including 16 in Shiprock and 11 in Tsaile. We 
will identify schools in Tsaile and Shiprock who meet the eligibility criteria for the study. The eligibility criteria 
will include having been in existence for at least three years, school size (have between 40 to 100 students in 
grades 3 and 4 combined), have more than two-thirds Navajo students and satisfy a garden site checklist that 
can overcome garden barriers (e.g. have access to water) (Figure 2). Information about potential schools will 
come from the initial phone screening and a school questionnaire. Each school will be contacted by phone and 
letter to assess their initial interest in participating in the study. After initial conversations, study staff will 
arrange a meeting with school faculty meeting to discuss the intervention and study procedures in detail. The 
meeting will provide detailed information on the student recruitment and data collection process and 
emphasize efforts to minimize disruption of daily classroom routine. For interested schools, we will also do an 
initial assessment of the school resources and garden site. From these meetings we hope to identify at least 
six schools, three in each community for further engagement. Our next phase with the schools will serve as a 
“run-in” period to the trial. During this time we will hold 
meetings with teachers and parents, and conduct initial 
surveys to gauge their level of interest, ability to engage in 
the types of evaluations used in the main study, and 
likelihood of engaging fully in the curriculum and school 
garden intervention. Our goal is to randomize a minimum of 
four schools (two in each community) that will participate for 
the duration of the project. If all schools qualify for the study 
on completion of run-in, we will randomize all six schools, 
two to intervention and four to delayed intervention. 
 
IV. 
INTERVENTION AND ASSESSMENT 
 
A. 
Yéego! Healthy Eating & Gardening Intervention 
Our intervention has two main components: a school garden and a healthy eating and gardening 
curriculum for students. It also has an ancillary component: family workshops to promote healthy eating and 
gardening at home. The theoretical framework for the intervention draws on the Social Ecological Model, which 
states that there are determinants at multiple levels that influence health behaviors, including the social and 
physical environment, organizations, and family.46 We have also incorporated Social Cognitive Theory, which 
states that environmental factors influence individuals and groups, but that individuals and groups can also 
influence their environment and regulate their own behavior.46 The school garden is an environmental feature 
that reinforces the skills, knowledge and behaviors taught in the curriculum, which in turn promote the 
collective efficacy of the students and their families to maintain healthy eating and gardening behaviors. 
School Gardens. At each school, we will establish a school garden following guidelines outlined by Life 
Lab and previous school garden projects.47 Ideally, school gardens will be located in a highly visible 
location in full sun, near a water source, fenced within a school play yard and accessible to the central 
school building, as well as school staff, students and family members. Gardens will consist of four durable 
raised garden beds (approximately 24 square feet each) filled with amended soil. The region is semi-arid so 
we will install appropriate irrigation systems that utilize available water resources efficiently including drip 
irrigation and rainwater harvesting. The garden will serve as a place for school staff and students to garden, 
Figure 2: Garden Site Pre-intervention 
checklist: 
 Supportive leadership and staff (for 
developing a garden) 
 Staff and volunteer interest in 
conducting garden maintenance 
 Garden site near the main school 
building(s) 
 Access to water at the garden site 
 Fencing and/or security for the garden 
or school to prevent animal browing 
and vandalism 

as well as an additional outdoor classroom for both student lessons and family workshops. The school will 
have primarily responsibility for maintaining the garden. However, they will receive technical assistance 
from the study team throughout the growing season related to planning, planting, maintaining and 
harvesting what is grown during the school year. We will continue to assist during the summer (between 
Years 2 and 3), when students and teachers are on summer break. However, we will encourage schools to 
identify staff or volunteers who can assist with maintenance during the summer months. 47 Plant selection 
will include vegetables that have grown well in our previous garden projects and informed by staff, student  
and family preferences. We envision a combination of cool season (e.g.leafy greens like kale and root crops, 
potatoes, onion) and warm season crops (fruiting crops) like tomato, chili pepper, and the “Three Sisters”: Navajo 
corns, squashes, and beans. As crops mature and are harvested, research staff and students will measure the 
garden yield by weight and counts, in order to assess how much the garden space can produce. The fruits and 
vegetables harvested from the garden will belong to the school. Many Navajo schools provide breakfast, lunch 
and a snack to their students. We will work with cooking staff to ensure that they can use the produce harvested 
from the garden for meals and snacks provided by the school. Teachers will also be encouraged to use the 
garden and its contents (social, insects, plants) as a teaching space for other subjects. Garden infrastructure 
and plant names with their culinary/medicinal/traditional uses will be posted on signs in both Navajo and English.  
Table 5. Healthy Eating Curriculum 
 
Healthy Eating and Gardening Curriculum. We will provide schools with our curriculum (developed and 
implemented in our current pilot study) for both healthy eating and gardening that covers the entire school year. 
Each content area consists of 12 lessons throughout the year and coordinated with the growing season (See 
Tables 4 & 5, total of 24 lessons). Lessons will be scheduled based on input from school staff, but will occur 
approximately two times per month. The curriculum was designed based on both formative research with the 
target population, previous school garden interventions, investigator expertise in theory-based interventions to 
promote healthy eating and gardening, and instructional design.9,36,48 The curriculum draws on Social Cognitive 
Theory, which posits that self-efficacy and observational learning are critical for promoting self-regulation and 
maintaining healthy behaviors.46 The curriculum meets N.M state standards in health education, science, and 
Unit 
Learning Objectives 
Example Activity 
1. Introduction & 
Kitchen Safety 
Kitchen safety 
Define personal and community health 
Practice kitchen safety skills 
Prepare and decorate journals 
2. Food 
Sovereignty 
Explain food access and availability 
Read a recipe to create a snack 
Community guest speaker to teach significance 
and prep. of kneel down bread 
3. Whole Foods & 
Nutrition 
Identify whole and processed foods 
Choose healthy food options 
Prepare snack from a recipe 
Analyze food labels and images 
4. Empty Calories 
Choose healthier sweeteners and low sugar 
drinks 
Taste test varieties of same drink with different 
sweeteners 
5. Fruits and 
Vegetables 
Identify different fruits and vegetables and 
understand why them is important 
Recognize My Plate 
MyPlate drawing activity 
Practice knife skills 
6. Fiber 
Identify strategies for incorporating more 
fiber into diet with fruits and vegetables 
Compare seed anatomy 
7. Traditional 
Foods 
Identify traditional foods and their nutritional 
or medicinal importance 
Community guest speaker will teach significance 
and prep. of blue corn mush 
Draw and press plants and herbs into notebook 
8. Food and 
Family 
Share foods and traditions from their family 
Learn to double a recipe for a group 
Read “Who’s in my family” about different family 
structures 
9. Garden to Table 
Describe participants and steps in a 
community food system 
Prepare a snack with local and seasonal 
ingredients, discussing where they came from 
10. Breakfast and 
Lunch 
Understand the importance of making 
healthy food choices at home and school 
Use kitchen skills to help prepare foods for lunch 
or snack at school 
11. Celebrations 
and Gatherings 
Prepare healthier meals for celebrations 
and gatherings 
Practice using a cookbook to find and prepare a 
recipe for next garden celebration 
12. Garden 
Celebration 
Plan and lead a harvest celebration 
Redefine personal and community health 
based on what they’ve learned 
Harvest and prepare foods from the garden for a 
celebration with the school community 

social studies for grades 3 and 4. By integrating the lessons into regular classroom activities, the interventionist 
can also help with required student assessment (i.e. pre/post learning) demonstrating growth relative to the state 
standards. 
Lessons will be co-led by our interventionist and a teacher from the school as part of the regular school day, 
consisting of about 45 minutes for each lesson. Our curriculum is focused on children in third and fourth grade. 
Lessons will be implemented for both grade groups on the same day, but at different times, according to the 
teachers’ schedules. This will allow for smaller groups and a lower teacher to student ratio.  
For the healthy eating curriculum, each lesson consists of an introduction to the topic, an activity that 
addresses the learning objectives for the lesson, snack preparation, writing tasks associated with their garden 
notebook, and a handout with the day’s recipe for the students to take home (Table 5). Lesson structure for the 
gardening curriculum is similar but includes time for garden maintenance in place of the snack preparation (Table 
6). Each lesson aims to increase student self-efficacy in performing gardening and healthy eating-related 
behaviors, through demonstration and activities. Self-regulation and healthy behaviors are reinforced by 
observational learning and opportunities to practice the desired behavior (e.g. weeding, food preparation). 
Students will receive a handout based on the lesson content that can be taken home, so that families are aware 
of what their student is learning and have information to start or maintain their own gardens. Many of the lessons 
incorporate reading from children’s books that were chosen based on their relevance to Navajo culture and/or the 
content of the lesson.  
Teacher Curriculum Discussion Groups. Third and fourth grade teachers from Shiprock and Tsaile area 
schools will be invited to participate in a group discussion on how to enhance the existing curriculum for the 
current study. Teachers will have the opportunity to provide feedback on how best to integrate Diné and AZ/NM 
state standards into the curriculum and provide suggestions for new content or materials needed to facilitate the 
curriculum within their schools. Teachers that attend the group discussion will be provided with light refreshments 
and receive $30 for their time. At the end of the academic school year, 3rd and 4th grade intervention teachers will 
be contacted for a 60-minute phone interview to learn about their perceptions of the Yéego! Healthy Eating and 
Gardening curriculum. The goal is to seek to improve the curriculum through understanding teacher perceptions 
of what worked well, what needs improvement and wat additional support is needed for future implementation.  It 
will also help to understand how delivery of the intervention contributes to study outcomes. Teachers will receive 
$30 for their time. 
 
Table 6. Gardening Curriculum 
Unit 
Learning Objective 
Example Activity 
1. Planning a garden 
Use seed packet information 
Understand how sun affects garden design 
   
2. Sowing and 
transplanting 
Follow garden plan 
Use proper technique for planting seeds 
Make garden plan. 
Make garden labels in English and Navajo 
3. Garden 
maintenance 
Perform weeding, watering and thinning 
Identify common weeds 
Explain what is needed to make a plant grow 
Read “Corn is Maize”. 
Model and have students practice weeding 
and watering 
4. Water 
Describe the water cycle, and how humans 
impact it. 
Explain how water quality affects human health 
Read “Snail Girl Brings Water: A Navajo 
Story” 
Model the water cycle. 
5. Compost  
Explain why compost is important  
 
Collect compost samples and examine 
them with magnifying glass.  
Record observations. 
6. Plant anatomy 
Identify plant parts and function 
Describe traditional uses and cultural 
significance of traditional craft 
Harvest and classify plants. Plant scarlet 
runner beans in observation cups. 
7. Traditional 
gardening 
practices 
Describe traditional growing and farming 
practices and how they related to food 
sovereignty 
Hear about traditional growing practices 
from local community member 
Implement one traditional garden practice 
8. Pollination 
Explain how pollination, fruit and seeds are 
linked 
Describe how and why to manage pests 
Read “Zinnis, or How the Corn was 
Saved.” 
Plant wildflowers. 

9. Seasonal crops 
Understand how seasons affect plants 
Descript how home and school gardens help 
localize the food system 
Create garden calendars. Observe seed 
and plant growth. 
10. Native plants and 
ecology 
Identify native plants and describe their 
traditional uses 
Plant native plants in the garden 
11. Food presentation 
and seed saving 
Describe methods for food preservation 
Identify food safety considerations 
Quick pickle vegetables for a snack. 
Create seed packets for saved seeds. 
12. Harvest 
Measure amount of produce harvested 
Practice safe food storage and preparation 
Weigh harvested produce and compare 
across garden plots using a bar graph. 
 
Family Workshops. In the second year of the intervention (Year 3), there will be quarterly healthy eating 
and gardening workshops for family and community members to attend. These events will focus on engaging 
school staff, students and their families in the garden and provide an opportunity for families to learn gardening 
and healthy eating topics together. They will also be open to the entire community (Shiprock or Tsaile), in order 
to help promote positive social norms about healthy eating and gardening. For this reason, this component is 
considered ancillary, and will be evaluated separately from the main intervention components, by tracking 
attendance. Each workshop will focus on a specific skill that families can use at home to either grow or prepare 
healthy food. Participants will also receive small prizes for attending, such as plants, gardening tools, seeds or 
cooking utensils. These events will be based on similar events conducted during our pilot of the school-based 
intervention that were well attended and well received by the Shiprock community. 
Due to COVID-19 Family Workshops Go Online. Due to the Navajo Nation, New Mexico, and Arizona 
responses to the COVID-19 pandemic, the planned in-person family workshops have pivoted to a video 
workshop series. The series is housed on the NMSU Agricultural Science Center website.  The “how to” 
workshop series provide family and community members the opportunity to learn about gardening and healthy 
eating through a short video.  The video series includes: 
1. Raised Bed Construction (with media mixes) 
2. How to Make Blue Corn Mush (from heathy eating curriculum activity) 
3. How to Make Apple Donuts (from heathy eating curriculum activity) 
4. Planting Peach Seeds 
5. Transplanting Nursery Fruit Trees 
6. Fruit Tree Pruning 
7. Cool Season Crops 
8. Seed Saving/Storage 
9. Tunnel Construction 
10. Frost Cover/Row Cover/Plastic Mulches (with ways to purchase resources) 
11. Navajo Spinach Food Preservation 
Videos are filmed by NMSU Agricultural Science Center staff, Diné College Extension Agents, Extension 
Agents from the San Juan County Cooperative Extension, Utah State University.  The original workshops and 
the video workshop series are designed to be open to the entire community. Accordingly,  the videos will be 
promoted and uploaded to the NMSU Agricultural Science Center website https://farmingtonsc.nmsu.edu/, an 
open-access public website. The NMSU website is maintained by the main NMSU campus in Las Cruses New 
Mexico, Dr. Kevin Lombard will be the direct contact.  Student participants in the Yéego! Healthy Eating and 
Gardening Project will receive a promotional e-flyer through their school announcing the video series. 
Video Production Timeline: 
 
B. 
Data Collection/Assessment 
After the end of the run-in period, we will obtain assent and consent from parents of children in the 
participating schools that are eligible to be randomized. This assent and consent will be for all the study 
assessments during the entire study period. In Year 2, we will survey the children and a parent (or index adult 
caregiver) at baseline (T1) which is at the beginning (August) and at follow-up (T2) which is at the end (June) 
of the school year. Timing of assessments will be staggered so that presence in the school at any one time 
point will occur on non-consecutive days, to minimize disruption in the classroom. Data assessment is quite 

time consuming since the surveys have to be read to the respondent in an interview format conducted 
individually. We will use electronic data collection methods to capture the responses from both the interviewer-
administered survey and from a culturally adapted virtual picture sort method.49,41 Response options will be bar-
coded on a screen displaying the picture of the groups of foods.  
Prior to the start of the school year, and after a successful run-in, information regarding the study will be 
sent out to all families in randomized schools. They will also be invited to attend an information night timed to 
coincide with a parent orientation or chapter house meeting to learn about the study in detail. Information about 
the study will also be visible in the school newsletter prior to the start of recruitment, posted on school websites 
and posters displayed at the school to invite students to participate in the study. The project will ask from the 
school administration staff the first and last name of students, grade and teacher in order to create individualize 
recruitment packets. Students will receive a recruitment packet from their teacher to be sent home with their 
daily schoolwork. The packet will include information about the study, child assent and adult caregiver 
permission and self-consent to participate in the study. Students will be encouraged to return their packets in 
one week to be eligible for a school-wide raffle. Raffle for past studies included gift certificates to a local 
restaurant, movie theatre or activity for the family. The top raffle prizes will be a $50 gift card for the family, 
additional prizes include tote bags and backpacks.  After the first week, a second round of packets will be 
distributed to the remaining students to reach the required recruitment goal of 60% of third and fourth grade 
students. In addition, to compensate teachers for their support of the packet process, classes that reach the 
60% enrollment goal will receive $50 worth of classroom teaching supplies.  The teachers will nominate what 
supplies their classroom will need.  Study staff will purchase the items up to $50 and deliver to the teachers.  
For the students consented to participate in assessment, study staff will identify a series of after school times 
for students to complete the baseline survey. Student and adult caregivers who are not able to attend an 
assessment session after school, will be provided the opportunity to conduct the assessment at their home or 
place of their choosing. Each student/adult pair completing the assessment will receive a monetary gift in the 
form of cash, gift card or small gifts for children valued at $5 (e.g., flashlight, water bottle, cinch-
sack/backpack). The starting cash amount for parent survey is $20 and child is $5. In order to maximize 
retention at later time points the survey incentive will increase by $5 at each time point. Other retention efforts 
include phone, email and text reminders.  A school champion for each school will be assigned by the principal 
to assist with enrollment and assessment logistics for each school.  The champion coordinates times for the 
assessment team to pick up completed enrollment packets, deliver new packets to teachers and assist with 
delivery of raffle prizes to schools and families.  As a token of appreciation for their assistance, an honorarium 
of $100 will be provided at the end of the 2020 and 2021 school year. 
 
Follow-up Assessment Notification 
About a month before the start of the follow-up surveys (T2 in 2020 and T3 in May 2021), teachers will send a 
notice home with consented students who participated in the Baseline (T1) survey informing them and their 
parents of another survey coming. The study staff will follow the same procedures outlined for the baseline 
assessment of the students. 
 
Parent/guardian survey.   
There are four methodologies for completing the parent/guardian survey. 
1. From the consented family, the parent completed the baseline survey and is available to complete the 
FU survey. 
2. From the consented family, the parent consented, but did not complete the baseline survey. They will 
be invited to complete the follow-up survey. 
3. From the consented family, the parent completed the baseline survey but is unable to complete the FU 
survey at any time in the follow-up window (T2 is April-May 2020). 
4. A 3rd or 4th grader or their family are requesting an opportunity to participate at follow-up but have not 
yet completed the family packet or consent or assented their child. 
 

1. The assessment coordinator will contact the parent who completed the baseline (the index 
parent/guardian) to again participate in the follow-up surveys (T2, and later T3).    
2. The assessment coordinator will contact the parent who consented to the baseline but did not complete the 
survey (the index parent/guardian), to participate in the follow-up surveys (T2, and later T3). 
3. If it is found that the index parent/guardian is not able to complete the survey, a new index parent/guardian 
can be appointed.  The new index parent/guardian will be contacted to complete Parent Survey and Verbal 
Participation Consent Form approved by IRB.  The verbal consent will be read and must be verbally 
affirmed by the parent/guardian prior to completing the parent survey interview. At the top of the parent 
follow up survey, there is a space for the interviewer to notate change in survey completer.  
 
New Student Enrollment: New students will not be actively recruited to participate in the study at T2 or T3.  If 
the new student or their parent wishes to participate on their own accord, they can request an enrollment 
packet from their teacher.  In this way, students enrolled at a participating school in the 3rd or 4th grade after the 
baseline assessment was completed will have the opportunity to participate in the assessment. The first step is 
for them to take home the enrollment packet for their parent/guardian to complete.  The child cannot participate 
in the survey without a completed packet. As before, the packet will include information about the study, child 
assent and adult caregiver permission and self-consent to participate in the study, and a Parent Family Survey 
(all documents IRB approved – see section VI List of Approved Documents).   The student and parent/guardian 
must complete the enrollment documents and return the sealed packet to the teacher.  The teacher will give 
the sealed packets to the school designated school champion to be securely locked in the assessment file 
cabinet until retrieved by the study staff.  Procedures for obtaining student follow-up survey and parent follow-
up survey will follow similar steps to those used at the baseline survey. 
 
CONTEXT   
New Mexico and Arizona State have mandated closure of all schools for the duration of the school year in 
response to slowing COVID-19 spread. The study has had to revise its protocol for obtaining the primary 
outcome measure that includes student follow-up assessment in April/May 2020. 
 
Student Follow-up Assessment (amended due to COVID-19) 
Preparation 
Yéego! Healthy Eating & Gardening project has mailing addresses (including PO Box numbers) for almost all 
of the 3rd and 4th grade students in all six schools. For those students for whom the study has no address, 
contact will be made via phone and email requesting mailing address. It is anticipated that we will obtain 
mailing addresses that will reach ALL the 3rd and 4th grade students. 
 
In addition to the mailed survey, parents/guardians that provided email addresses will be sent an email with a 
secure link to the follow-up survey. The weblink will send participants to a new virtual server with more 
restrictive access.  The Yeego Server and the process to protect the files stored locally at Fred Hutch was 
approved by Information Security Office and IRB 08-12-2019. 
 
Awareness communication plan 
▪ 
Text blast/robocall: Yéego! staff will work with the principals of the enrolled schools for permission to 
use the teacher text blast or robocall system currently in place at the school. Text blast/robocall will be 
sent only to enrolled 3rd and 4th graders.  The text blast/robocall will alert the student’s parent/guardian 
that Yéego! staff will be in contact by email and/or phone regarding the follow up survey. 
 
Individual Communication to provide tailored link and survey modality choice 
▪ 
Email push: The Nutrition Assessment Shared Resources (NASR) will generate a standard email with a 
unique/personalized participant log-in link so students and parents/guardians can complete the follow-
up survey online.  96% of parents/guardians provided an email when enrolling into the study. 

▪ 
Text/Phone: The data collection team will contact participants by phone or text at the number provided 
on the Family Survey during enrollment. The call will take place after the text blast/robocall to 
participants and the email push.  The purpose of the call is to determine the best modality for 
administering the survey.  Prior to the phone call, the data collector will check to confirm whether an 
online survey has been completed. The data collector will let the participant know they can complete 
the survey online, by mail or by phone. The call could lead to a phone survey completion. 
 
Follow-up survey delivery 
▪ 
Online: The participant can complete the survey online. The Yeego study will be adding the capacity to 
collect online follow-up data directly from participants. An additional virtual server has been set up to 
host follow-up questionnaires. Data transmission from the participant to the questionnaire site will be 
encrypted via transport layer security (TLS). The questionnaire server will send participant responses to 
the encrypted study database, which is hosted on a separate server that is not accessible outside the 
Hutch network. Participants will be sent a participant-specific link by email. The link will direct them to 
the follow-up questionnaires. There is no personally identifying information presented or requested in 
the follow-up questionnaires. 
▪ 
Mail: A packet will be sent to the mailing address provided. It will contain a cover letter, student/child 
survey with face sheet, parent/guardian survey with face sheet),and a return postage-paid envelope. 
Note: For a household where the parent/guardian did NOT complete a baseline survey, no parent 
follow-up survey will be included.  
The assessment goal is to get as many of the original students and parent/guardians who completed 
baseline survey to complete the follow-up survey. In order to achieve a high response rate, the cover 
letter will include a phone number for the student/parent guardian to call if they prefer to conduct the 
interview over the phone, and an email to request a web-link if the student/parent guardian prefers to 
complete the survey online. The cover letter will also include a description of the incentives for 
completing the survey(s). 
▪ 
Phone: The parent/guardian of the child will be contacted by phone (see individual communication and 
modality above). The parent can choose to have the child complete the interview over the phone at that 
time with a data collector, or can schedule a more convenient time to complete the survey by phone.  
The student/child survey and parent survey participants can use the hardcopy mailed survey as a guide 
for the phone interview. 
Non-responder calls:  
Two weeks after the initial mailing, non-responders will be contacted by phone to confirm they received the 
mailed packet, and to check their preferred modality for completing the survey (paper, phone or online).  Once 
this preference is communicated (via mail, phone or email) with the study interviewer, they will arrange a time 
with the student (and the parent/guardian for the subset completing parent surveys) to complete the survey 
over the phone. The student can use the paper survey as a guide.  
Note: For those participants without phone numbers, a second mailing will be sent two weeks after the original 
mailing. 
C. 
Outcome Measures 
The primary outcomes for this randomized controlled trial are differences in changes from T1 to T2 in 
healthy eating behaviors and gardening participation and self-efficacy in the children from the intervention 
school relative to the children from the delayed intervention school(s). Assessments are restricted to 3rd and 
4th grade because of greater reliability among children aged 8 or older.  
Child Healthy Eating Behaviors. Tendency to Choose Fruit and Vegetables to Eat, Assessing dietary 
intake in elementary school age children is notoriously difficult. Different simple approaches to approximating 
choices or eating behaviors have been attempted50-52, including use of self-efficacy scales37,38. Questions using 

a 4 point Likert scale were modified from two other studies of children, using 5-point53 and 3-point Likert54 
scales. Seven questions ranging from “At lunch, I usually choose to eat vegetables, such as celery sticks or 
carrots” to a reverse code of “During snack time, I usually choose to eat cookies or crackers” are combined 
and averaged for an overall score. In a recent study in children,55 the scores ranged from 1.14 to 3.86, with an 
average of 2.44 (s.d. =0.48). Healthy Eating Score. We will use the picture sort method developed in our 
current study, which allows us to estimate the frequency of eating foods that comprise ten major food 
groupings of the Navajo diet,41 including breads; vegetables and salad; fruits; beverages; soups or stews; 
cereals; dairy and eggs; rice, pasta etc; meat, chicken or fish; and desserts and snacks. Sufficient detail within 
the broad groupings was retained to allow estimation of six of the eleven components of the AHEI. 42 Elements 
of the index that we were able to include are vegetables, fruits, whole grains, nuts and legumes, as well as 
sugar sweetened beverages and fruit juice, and red/processed meat. Trans fat, long chain fats, PUFA, sodium 
and alcohol will not be assessed in the children. The resulting Healthy Eating Score has a range of possible 
values from 0 to 47, and in our current study, the mean score was 14.6. 
Child Gardening Participation and Self-efficacy. Gardening at Home. We will ask children if they have a 
garden at home, and if so how often they do gardening activities there. Responses had good variability in our 
current study – just over half reported affirmatively for “like to garden” and “have a place to garden” (Table 3). 
The analytic variable used will be proportion reporting gardening at home at least sometimes. Gardening self-
efficacy. Self-efficacy questions regarding how confident they are in their ability to perform the behaviors come 
from the LA Sprouts studies.9,36 The measures were evaluated for validity and reproducibility in schools in the 
Los Angeles area.36 The self-efficacy variable used in the analysis will be a combined six-item likert scale. 
Parent dietary behaviors. Dietary intake questions include fruit and vegetable consumption using an 
instrument used in the 5 a Day study, as well as soda and fast food consumption. This set of obesity related 
dietary behaviors56 will be combined into an index (Barrington & Beresford, personal communication). The 
parent will also complete the virtual picture sort frequency method following the approach used in our current 
study (originally developed in an African American community49 and modified for this study using foods 
commonly consumed by Navajo)41. Again, the weekly frequencies will be converted to a relative healthy food 
ratio (healthy foods to total foods) for the parent, based on AHEI categories42. 
Parent gardening behaviors. Our parent gardening frequency measure assesses typical frequency of 
gardening per week in the past three months, which we have adapted and modified from our previous studies 
to date. We will also ask about the presence of a garden at the home, frequency of participation in any 
gardening in the child’s school or, if applicable, their home garden. Additional questions concerning degree of 
familiarity about what is being planted/grown/harvested in the school garden will be included. 
Intermediate outcomes. For children, these include determinants of dietary behavior consistent with the 
approach used in the LA Sprouts study,9 and the vegetable intake, food security and family relationships 
measures used in the Community Gardening Project in Oregon. 57 Gardening capability questions will be 
developed for children to indicate how well they know how to do specific gardening tasks that are taught in the 
curriculum (e.g. planting, weeding, watering, harvesting). We will also assess the participation of the students 
in the school garden, and the adoption by the students of positive attitudes towards growing vegetables, fruits 
and making healthy food choices.  
D. 
Process Measures: Recruitment, Retention and Fidelity 
We will assess recruitment, retention and fidelity using logs, tracking forms and checklists kept by the 
Project and Intervention Coordinators. We will also take minutes at all meetings with project staff, school staff 
and community advisors where recruitment, retention, reach, participant satisfaction, and fidelity will be 
regularly discussed. Recruitment. Data collectors will document the number of participants approached and 
recruited into the study in both the intervention and delayed intervention comparison group. Retention. Data 
collectors will document the number of eligible participants that complete each assessment. Intervention 
Fidelity. We will use checklists to assess fidelity to the intervention protocol during lessons. 
Teacher/Interventionist Checklist: Teachers will complete checklists at the end of each lesson to gauge fidelity 
of curriculum implementation. Based on previously outlined session themes and activities, instructors will 
report to what degree session specific content was addressed. Instructors will also be asked to comment on 

session materials and preparation, noting things that inhibited or facilitated their ability to deliver program 
content, or any variation in participation. Observer Checklist: A data collector will be present at each lesson to 
complete an observation checklist, reporting the degree to which the intervention protocol is followed. This will 
include monitoring attendance, level of participation/exposure, content covered, and session logistics including 
materials provided and degree of preparation. Data collectors will also note barriers and facilitators to 
participation and engagement in session activities. Data from the checklists will be analyzed to assess fidelity 
to the intervention protocol.  
E. 
Analysis Plan 
Two of our four primary outcome measures in children (tendency to choose fruit and vegetables to eat 
during snacks/meals and gardening self-efficacy) will be measured through questions that use a Likert-type 
scale with four response options. With numeric codes assigned to each response option, means and standard 
deviations will be calculated per question and overall. Thus, possible mean values range from one to four. The 
intention to treat analysis will be a t-test comparing the change in mean values from baseline (beginning of 
school year at T1) to follow-up (end of school year at T2) in the intervention schools to those changes in mean 
values in the schools receiving the delayed intervention. This differential change in groups between T1 and T2 
is the estimated intervention effect. The estimated effect of the intervention will also be analyzed using linear 
mixed models with T2 individual outcome as the dependent variable and intervention assignment as the  
independent variable, adjusting for T1 individual outcome and school random effect. It will also allow for 
adjustment for additional covariates (school within intervention group if applicable) and for known or probable 
individual level confounders. Information from all responding students will be included in the analysis, with 
adjustment for repeated measures (expected to be the majority of the students). This will assess robustness of 
inferences from the simpler model. A sensitivity analysis without adjusting for possible intra-school correlations 
will be performed using linear regression models. In addition, the Akaike Information Criterion will be compared 
between the simpler model and the theoretically correct multilevel model to check model fit.  
The picture sort method uses references to 26 commonly consumed food items by Navajo41 chosen to 
represent six of the broad food components captured within the AHEI,42 and four other Navajo food groups. 
Frequency of consuming foods from each group, with specific focus on the six AHEI relevant components will 
be estimated and compared across schools. The healthy components are fruits, vegetables, whole grains, and 
nuts and legumes, and the so-called “unhealthy” components based on AHEI scoring are sugar-sweetened 
beverages and fruit juice, and red/processed meat.42 Differential change in the derived healthy eating score will 
be estimated, and evaluated using a t-test, conservatively, assuming a Normal distribution for the score, based 
on the Central Limit Theorem. Similarly, the proportion of children who participate in gardening at home will be 
calculated for each school, and the differential change estimated and evaluated using a z-test for proportions.  
Secondary outcomes, including those collected from the parents of participating children, will be analyzed 
similarly. Mean values and standard deviations for scored variables will be calculated, and intervention effects 
estimated, and evaluated using t-tests. Frequencies will be estimated for categorical outcomes and 
intervention associated differences in frequency distributions across categories will be evaluated using 
Pearson's Chi-square test. Since both parent and child data will be collected, parent-child pairs will be created 
and explored, including the use of generalized mixed models to account for within-family correlations. The form 
of dyad analysis used will take into account that the members of the dyad are distinguishable.58,59 
V. 
Protection of Human Subjects 
A. 
Risks to Human Subjects 
Human Subjects Involvement, Characteristics, and Design. The primary study population is children, both 
male and female, in grades 3 or 4. One member of their adult family (21 years or older) is included in the 
secondary study population.  Because of the multicomponent nature of the intervention, including the school 
garden, and parent workshops, participation in the intervention activities will include children in other 
elementary grades and other parents.  The proposed study will take place in elementary schools within the 
Shiprock, NM and Tsaile, AZ area; both rural areas located within the Navajo Nation.  The majority of the 

participants in the study will be American Indian (AI), primarily members of the Navajo Nation. It is anticipated 
that as many as 960 participants will be formally enrolled in the study: 80 3rd and 4th grade students within each 
of 6 distinct schools (three in Shiprock, 3 in Tsaile), plus one parent/caregiver for each child.  Participants will 
be recruited through the enrolled, participating elementary schools selected.   
Study Procedures, Materials, and Potential Risks. Schools will be recruited to the study and will take part in 
a “run-in” including planning with the study, and an evaluation of readiness to complete study surveys.  We will 
recruit from 6 elementary schools in two communities (two schools in Shiprock, NM and three schools in 
Tsaile, AZ). We will recruit and enroll children in grades 3 and 4 (ages 8-11) who attend the selected 
elementary schools participating in the proposed study. 
 
Data will be collected for research purposes only. Materials to be obtained include interviewer-administered 
questionnaires and anthropometric measures (height and weight) at three time points of the proposed study; at 
the beginning-T1 (August) and end-T2 (June) of the intervention school year and the end of the second school 
year-T3, once the delayed intervention has completed the intervention. We will assess process evaluation 
measures including recruitment, retention and intervention fidelity. 
 
The interviewer-administered questionnaires will be completed online with questions constructed from 
items taken from the IRB approved previous study, “Engaging School and Family in Navajo Gardening for 
Health” and valid measures adapted minimally to be culturally relevant and understood by children and adult 
members of the Navajo community. The questionnaire for children will include healthy eating behaviors and 
gardening participation and self-efficacy including fruit and vegetable consumption at meals, relative frequency 
of health foods, gardening participation, and gardening self-efficacy.  The parent/caregiver questionnaire will 
include dietary intake questions, fruit and vegetable consumption using the instrument from the 5 A Day study, 
as well as soda and fast food consumption, obesity related dietary behaviors and gardening frequency 
measures.  Both parent and child will complete a virtual picture sort frequency method following the 
approached used in our current study. (originally developed in an African American community and modified 
for this study using foods commonly consumed by Navajo). Weekly frequencies will be converted to a relative 
healthy food ratio (healthy foods to total foods) based on the Alternative Healthy Eating Index (AHEI) 
categories.  
There are minimal risks associated with participating in the survey assessments.  It is possible that some 
participants (adult or child) may experience discomfort when answering questions about their health behavior. 
Participants will be informed that they do not have to answer any questions that make them feel uncomfortable.  
Finally, risks may include feelings of embarrassment, for children, during body measurements (height and 
weight). All staff will be trained to be aware of such discomfort, how to react in this situation, how to ease 
participants, and provide outside resources when needed. 
As a physical out-door activity, the act of gardening can occasionally produce risks including cuts, scrapes, 
and sunburn.  In most circumstances, accidents occurring in a garden are superficial.  When proper 
precautions are taken (i.e. wearing appropriate footwear, sunscreen, hat, gloves) and training is given on the 
appropriate use of tools, accidents are usually preventable.  Participants will be informed of the risk of out of 
door activities and advised to wear appropriate clothing, sunscreen and hat and to drink plenty of water. 
B. 
Adequacy of Protection Against Risks 
Informed Consent and Assent. Prior to the start of the school year, and after a successful run-in, information 
regarding the study will be sent out to all families in randomized schools.  They will also be invited to attend an 
information night to learn about the study in detail.  Information about the study will also be visible in the school 
newsletter prior to the start of recruitment, posted on school websites and posters displayed at the school to 
invite students to participate in the study. The project will ask from the school administration staff the first and 
last name of students, grade and teacher in order to create individualize recruitment packets.  Students will 
receive a recruitment packet from their teacher to be sent home with their daily schoolwork.  The packet will 
include information about the study, child and adult caregiver assent and consent to participate in the study.  
We will obtain assent and consent from parents of children in the schools. This assent and consent will be for 
all the study assessments during the entire study period.  

For the students consented to participate in assessment, study staff will identify a series of after school 
times for students to complete the baseline survey.  Student and adult caregivers who are not able to attend an 
assessment session after school, will be provided the opportunity to conduct the assessment at their home or 
place of their choosing.  
Protections Against Risk. All individuals who participate in the surveys will be told that they can decline to 
answer any specific questions. All will be told they can stop participation at any time.  Any paper records will be 
kept in a locked cabinet for up to three years.   
Confidentiality of the study participants will be protected in this project. All participants will be assigned a 
study identification (ID) number. Information linking the participant name and study ID number is kept in a 
password protected computer file, separate from the survey responses and other data collected in the study. 
Access to the linked data is under the oversight of the Joint PIs, Dr. Lombard, at the NMSU-ASC, Farmington 
and Dr. Beresford of the FHCRC, who are responsible for maintaining the confidentiality. Questionnaire data is 
coded and managed as data files in a separate, protected part of the computer network. No information is 
released that could lead to the identification of any participating individual.  Access to computer-stored 
information will require simultaneous knowledge of the data format, computer language, file name, and 
password. No individuals will be identified in any reports from the study. 
We regard the risk of participation in this project as relatively slight.  We will take care that every 
interviewer/facilitator is trained to handle an adverse situation sensitively and empathically, if a participant does 
experience significant distress during focus groups, interviews, or questionnaire completion.  We will be 
prepared to consult with our IRB and/or human resources in the event that an adverse situation is reported.  All 
participants will be given the name and number of a person in IRB to contact if an adverse situation should 
arise.   
In the school gardens, participants will receive training in appropriate use of garden tools and be 
encouraged to wear appropriate attire.    
Vulnerable Subjects. The individual level, school level, family level and community level intervention focuses 
on improving health of children and their parent/caregiver by integrating healthy eating and gardening 
throughout Shiprock, NM and Tsaile, AZ area.  While the study is considered minimal risk, it is understood that 
permission to participate in the study means the agreement of parent or guardian to the participation of their 
child.   
The institutional review board at the Fred Hutchinson Cancer Research Center has strict guidelines 
regarding the participation of children in research. All policies and recommendations will be followed.   The IRB 
will approve all mechanisms for soliciting the assent of the children and the permission of their parents or 
guardians.  
C. 
Potential Benefits of the Proposed Research to Participants and Others 
Many aspects of the proposed study may be beneficial to the participants and their families. Benefits may 
include learning about healthy eating and how to garden, greater communication about healthy meals among 
families, gaining satisfaction knowing that they are providing information that may help other people within the 
Navajo community and their families in the future.   
D. 
Importance of Knowledge to be Gained 
This study will provide important information about preparation, storage, health benefits of foods and using 
school gardens to improve the vegetable and fruit consumption and general health among people of the 
Navajo Nation. Given the broad engagement with the school communities in project, our hope is that the 
schools and families involved will also become health champions in their communities, passing on their 
knowledge of healthy eating and gardening to others in their community and encouraging participation in our 
future studies. The project also serves to maintain an important relationship between the Navajo Nation tribal 
leaders and the NMSU ASC for their other collaborative research projects.  This relationship makes it possible 
for us to sustain our efforts with our Navajo partners and provides a mechanism to transfer research findings 
directly to Navajo Nation policy makers.   

The knowledge gained will lay the groundwork for an R01 type proposal, including specification of both the 
intervention and outcome measures, that would formally evaluate intervention effectiveness of the intervention 
using an experimental design.   
E. 
Data Safety Monitoring Plan 
This plan pertains to the intervention activities involving the garden.  The risk of intervention activities is 
small due to the modest levels of exertion of the proposed project and the care in implementation of all 
gardening activities. Anticipated risks, if any, may include minor strain injuries sustained while being physically 
active.  At the end of each class, staff will ask participants if they have experienced any muscle soreness or 
strains or other concerns. The research staff will record positive responses. The research staff will carry a first 
aid kit to all events to attend to any minor bruises, cuts or other injuries experienced by youth. Each week the 
research staff will send a report to the PIs. The PIs will track the concerns/problems and assess for any 
patterns that might emerge. If a trend or pattern emerges, the PIs will consult with the FHCRC IRB and 
adjustments to the program will be made accordingly.  
Should any adverse event occur, the staff monitoring the intervention will inform the Community field manager 
within the hour. The community field manager will inform the PI of any adverse event within 24 hours. The PI 
will file an adverse event form with FHCRC IRB. The PI will send a copy of an adverse event report submitted 
to the FHCRC IRB to the NIH within 48 hours. We will track expected and adverse research related events and 
monitor over time.  
 
VI. 
LIST OF STUDY DOCUMENTS 
A. 
Participant Recruitment & Enrollment 
1. Parent Consent – approved 8/31/19 
2. Youth Assent – approved 8/31/2018 
3. Parent Consent 2 – approved 3/29/19 
4. Parent Consent 3 – approved 7/11/2019  
5. Youth Assent 2 – approved 7/11/2019 
6. Parent Consent 4 – approved 9/05/2019 
7. Youth Assent 3 – approved 9/05/2019 
8. Parent Verbal Consent – 01/16/20 
 
B. 
Assessment 
1. Baseline Questionnaire – approved 8/31/2018 
2. Parent/Guardian Baseline Questionnaire – approved 7/3/19 
3. Family Survey – approved 7/3/19 
4. 3rd and 4th grade Student Baseline Questionnaire – approved 7/3/19 
5. Baseline Questionnaire (T1) – Parent/Child electronic survey – approved 8/12/19 
6. Follow Up Questionnaire (T2) – approved 01/16/20 
C. 
Study Approach Documents & Intervention 
1. School Information Sheet – approved 7/3/19 
2. Assessment Overview Document – approved 7/3/19 
3. Recruitment packet documents – approved 7/3/19 
a. Intervention Later Information Sheet 
b. Intervention NOW Information Sheet 
c. Parent Instruction Sheet 
4. Study Logo – approved 7/11/2019 
5. Principal Support Letter template – approved 7/11/2019 
6. Intervention Curriculum – approved 8/12/19 

7. Follow up Assessment Parent/Guardian Postcard – approved 01/16/20 
8. Follow up Assessment Child/Student Postcard – approved 01/16/20 
9. Follow up Assessment Parent/Guardian Call Script – approved01/16/20 
10. Revised Intervention Curriculum Part I – approved 1/28/20 
11. Revised Intervention Curriculum Part II – approved 3/12/20 
12. Family Update Letter – COVID-19 – approved 3/19/20 
 
 
 

VII. 
REFERENCES 
1. 
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