Feasibility and Acceptability of Home Use Continuous Glucose Monitors for Type 2 Diabetes Risk Evaluation in Youth
Phase: NA
Conditions: Overweight and Obesity, PreDiabetes, Insulin Resistance
Sponsor: Mary Ellen Vajravelu, MD

 
 
  
Title: 
Feasibility and Acceptability of Home Use of Continuous 
Glucose Monitors for Type 2 Diabetes Risk Evaluation in 
Youth 
Short Title 
CGM for T2D Risk Evaluation 
Drug or Device 
Name(s): 
N/A 
FDA IND 
N/A 
Regulatory Sponsor: 
N/A 
eIRB Number :  
STUDY22030082 
Protocol Date:                   April 19, 2022 
Amendment 1 Date: August 9, 2022 
Amendment 3 Date: October 31, 2022 
Amendment 2 Date: October 12, 2022 
Amendment 4 Date: February 2, 2023 
Sponsor: Endocrine Fellows Foundation; Tanner Scholar Advancing Health Equity Award 
 
Study Principal Investigator: Mary Ellen Vajravelu, MD MSHP  
Children’s Hospital of Pittsburgh 
Division of Pediatric Endocrinology, Diabetes, and Metabolism 
University of Pittsburgh School of Medicine 
email: MaryEllen.Vajravelu@pitt.edu 
 

  
 
 
 
  
 
 
 
ii 
1 
CONTENTS 
ABBREVIATIONS AND DEFINITIONS OF TERMS .......................................................................................... IV 
ABSTRACT...........................................................................................................................................................................V 
PROTOCOL SYNOPSIS................................................................................................................................................. VI 
TABLE 1: SCHEDULE OF STUDY PROCEDURES .......................................................................................... XII 
FIGURE 1: STUDY DIAGRAM ............................................................................................................................... XIII 
2 
BACKGROUND INFORMATION AND RATIONALE ................................................................................ 1 
2.1 
INTRODUCTION .................................................................................................................................................... 1 
2.2 
NAME AND DESCRIPTION OF INTERVENTION .................................................................................................. 2 
2.3 
RELEVANT LITERATURE AND DATA................................................................................................................. 2 
2.4 
COMPLIANCE STATEMENT ................................................................................................................................. 3 
3 
STUDY OBJECTIVES ............................................................................................................................................. 3 
3.1 
PRIMARY OBJECTIVE .......................................................................................................................................... 3 
3.2 
SECONDARY OBJECTIVES................................................................................................................................... 3 
4 
INVESTIGATIONAL PLAN.................................................................................................................................. 4 
4.1 
GENERAL SCHEMA OF STUDY DESIGN............................................................................................................. 4 
4.1.1 
Screening Phase ............................................................................................................................................. 4 
4.1.2 
Study Visit........................................................................................................................................................ 4 
4.1.3 
Observation Period ....................................................................................................................................... 5 
4.1.4 
Individual Interview and Disordered Eating Questionnaire.................................................................. 5 
4.1.5 
Data Collection .............................................................................................................................................. 6 
4.2 
STUDY DURATION, ENROLLMENT AND NUMBER OF SITES........................................................................... 6 
4.2.1 
Duration of Subject Study Participation.................................................................................................... 6 
4.2.2 
Total Number of Study Sites/Total Number of Subjects Projected........................................................ 6 
4.3 
STUDY POPULATION ........................................................................................................................................... 6 
4.3.1 
Inclusion Criteria........................................................................................................................................... 6 
4.3.2 
Exclusion Criteria.......................................................................................................................................... 7 
5 
STUDY PROCEDURES........................................................................................................................................... 7 
5.1 
PHONE SCREENING .............................................................................................................................................. 7 
5.2 
STUDY VISIT ........................................................................................................................................................ 7 
5.3 
OBSERVATION PERIOD, DAYS 1-10 .................................................................................................................. 8 
5.3.1 
Non-Challenge Days:.................................................................................................................................... 8 
5.3.2 
Glucose Challenge: day of participant’s choice between Days 3 and 9 .............................................. 8 
5.3.3 
Mixed Meal Challenge: day of participant’s choice between Days 3 and 9 ....................................... 8 
5.3.4 
Removal and Return of CGM and ActiGraph: Day 10 ........................................................................... 9 
5.4 
INDIVIDUAL INTERVIEW AND DISORDERED EATING QUESTIONNAIRE: ANY TIME BETWEEN DAY 10 OF 
OBSERVATION PERIOD AND 1 MONTH AFTER STUDY VISIT ........................................................................................ 9 
5.5 
CGM, ACTIGRAPH DATA EXTRACTION .......................................................................................................... 9 
5.6 
SUBJECT COMPLETION/WITHDRAWAL ............................................................................................................ 9 
5.6.1 
Early Termination Procedures .................................................................................................................. 10 
6 
STUDY EVALUATIONS AND MEASUREMENTS..................................................................................... 11 
6.1 
SCREENING AND MONITORING EVALUATIONS AND MEASUREMENTS...................................................... 11 
6.1.1 
Medical Record Review .............................................................................................................................. 11 
6.1.2 
Physical Examination.................................................................................................................................. 11 
6.1.3 
Vital Signs ..................................................................................................................................................... 12 
6.1.4 
Laboratory Evaluations .............................................................................................................................. 12 
6.1.5 
Medical History, Family History, Social History Questionnaire ........................................................ 12 

 
 
 
 
  
 
 
 
iii 
6.1.6 
Interview and Disordered Eating Questionnaire ................................................................................... 12 
6.2 
EFFICACY EVALUATIONS ................................................................................................................................. 13 
6.3 
SAFETY EVALUATIONS ..................................................................................................................................... 13 
7 
STATISTICAL CONSIDERATIONS................................................................................................................ 14 
7.1 
PRIMARY ENDPOINT ......................................................................................................................................... 14 
7.2 
SECONDARY ENDPOINTS .................................................................................................................................. 14 
7.3 
CONTROL OF BIAS AND CONFOUNDING......................................................................................................... 14 
7.4 
STATISTICAL METHODS ................................................................................................................................... 14 
7.4.1 
Analysis of Primary and Secondary Outcomes of Interest ................................................................... 14 
7.4.2 
Qualitative analysis ..................................................................................................................................... 15 
7.4.3 
Exploratory analyses................................................................................................................................... 15 
7.4.4 
Missing Data................................................................................................................................................. 15 
7.5 
SAMPLE SIZE AND POWER ............................................................................................................................... 16 
8 
SAFETY MANAGEMENT ................................................................................................................................... 17 
8.1 
CLINICAL ADVERSE EVENTS ........................................................................................................................... 17 
8.2 
ADVERSE EVENT REPORTING.......................................................................................................................... 17 
8.3 
IRB/IEC NOTIFICATION OF SAES AND OTHER UNANTICIPATED PROBLEMS .......................................... 17 
8.3.1 
Follow-up report .......................................................................................................................................... 17 
8.4 
INVESTIGATOR REPORTING OF A SERIOUS ADVERSE EVENT TO SPONSOR .............................................. 17 
8.5 
MEDICAL EMERGENCIES .................................................................................................................................. 18 
9 
STUDY ADMINISTRATION............................................................................................................................... 19 
9.1 
DATA COLLECTION AND MANAGEMENT ....................................................................................................... 19 
9.2 
CONFIDENTIALITY............................................................................................................................................. 20 
9.3 
REGULATORY AND ETHICAL CONSIDERATIONS ........................................................................................... 20 
9.3.1 
Data and Safety Monitoring Plan ............................................................................................................. 20 
9.3.2 
Risk Assessment............................................................................................................................................ 21 
9.3.3 
Potential Benefits of Trial Participation.................................................................................................. 23 
9.3.4 
Risk-Benefit Assessment.............................................................................................................................. 23 
9.4 
RECRUITMENT STRATEGY ............................................................................................................................... 23 
9.5 
INFORMED CONSENT/ASSENT AND HIPAA AUTHORIZATION ................................................................... 23 
9.5.1 
Screening ....................................................................................................................................................... 23 
9.5.2 
Informed consent.......................................................................................................................................... 24 
9.5.3 
Re-Consent Plan for Subjects Who Reach Age of Majority ................................................................. 24 
9.6 
PAYMENT TO SUBJECTS/FAMILIES ................................................................................................................. 24 
9.6.1 
Reimbursement for travel, parking and meals ........................................................................................ 24 
9.6.2 
Payment Schema .......................................................................................................................................... 24 
10 
PUBLICATION ........................................................................................................................................................ 25 
11 
REFERENCES ......................................................................................................................................................... 26 
 

  
 
 
 
  
 
 
 
iv 
ABBREVIATIONS AND DEFINITIONS OF TERMS 
 
 
 
 
 
 
AE 
CAYAH 
BMI 
CGM 
PCTRC 
PHI 
SAE 
T2D 
OGTT 
HbA1c 
 
 
Adverse event 
Center for Adolescent and Young Adult Health  
Body mass index 
Continuous glucose monitor 
Pediatric Clinical and Translational Research Center 
Protected Health Information 
Serious adverse event 
Type 2 Diabetes 
Oral glucose tolerance test 
Hemoglobin A1c 
 
 

  
 
 
 
  
 
 
 
v
ABSTRACT 
Context: Youth-onset type 2 diabetes (T2D), an increasingly common and aggressive 
disease that disproportionately impacts racial and ethnic minorities, presents several 
diagnostic challenges.The screening tests currently used in practice, including hemoglobin 
A1c (HbA1c), fasting glucose, and 2-hour oral glucose tolerance test (OGTT), have 
significant drawbacks. Real-time continuous glucose monitors (CGM) are promising new 
tools for risk stratification in individuals with dysglycemia, but whether use of CGMs to 
evaluate type 2 diabetes risk in free-living youth is feasible and acceptable to patients and 
families is unknown. 
Objectives: The primary objective is to determine the feasibility of CGM-based type 2 
diabetes risk evaluation in youth, as measured by adequacy of CGM data capture and 
nutrition logging quality and completion during at-home glucose challenge. Secondary 
objectives are to determine the test performance characteristics of at-home, CGM-measured 
glucose challenge as compared to a gold-standard laboratory-based 2-hour OGTT; and to 
determine the acceptability of use of CGM for at-home dysglycemia evaluation as an 
alternative to clinical 2-hour OGTT. 
Study Design: prospective observational study 
Setting/Participants: Pubertal or post-pubertal 8-18 year-old children and adolescents with 
overweight/obesity (BMI≥85th percentile for age/sex, or ≥25 kg/m2 if =18 years old), who 
have or are at risk for prediabetes or type 2 diabetes, and attend the Endocrinology or 
Adolescent Medicine outpatient clinic at the Children’s Hospital of Pittsburgh; 40 
participants will be recruited. 
Study Interventions and Measures: Vitals, body size measurement, pubertal status, medical 
history, and laboratory assessments including oral glucose tolerance test and hemoglobin 
A1c will be assessed at one in-person study visit after overnight fast. Participants will wear 
continuous glucose monitor and wrist-worn actigraphy device for physical activity and sleep 
measurement for 10 days beginning on the day of the study visit, then return the monitors by 
mail. During the 10 day wear period, participants will respond to text message-based 
surveys to document food intake, physical activity, and sleep times and will complete two 
at-home challenges: 1) glucose challenge using study-provided glucose beverage that is 
identical to that they consume during clinical oral glucose tolerance test; and 2) food 
challenge with mixed carbohydrate/fat/protein-containing food of their choice. Glucose 
trends during these at-home challenges will be compared with oral glucose tolerance test 
obtained during the study visit. Individual interviews will be conducted upon completion of 
CGM wear to assess acceptability of the use of at-home glucose challenge and CGM wear as 
a strategy to evaluate diabetes risk in youth.  
 
 
 

  
 
 
 
  
 
 
 
vi 
PROTOCOL SYNOPSIS 
Study Title 
Feasibility and Acceptability of Home Use of 
Continuous Glucose Monitors for Type 2 Diabetes Risk 
Evaluation in Youth 
Funder 
Institutional funds 
Study Rationale 
Youth-onset type 2 diabetes (T2D), an increasingly 
common and aggressive disease that disproportionately 
impacts racial and ethnic minorities, presents several 
diagnostic challenges. The rapid loss of glycemic control 
soon after T2D diagnosis makes early identification an 
important goal in pediatrics, and risk-based screening has 
been recommended for children for over two decades. 
However, the screening tests currently used in practice, 
including hemoglobin A1c (HbA1c), fasting glucose, and 
2-hour oral glucose tolerance test (OGTT), have 
significant drawbacks. Real-time continuous glucose 
monitors (CGM) are promising new tools for risk 
stratification in individuals with dysglycemia. These 
patient-worn medical devices measure interstitial glucose 
every 5 minutes and offer glimpses into an individual’s 
everyday life, which may include consumption of 
carbohydrates in amounts larger than that assessed in an 
OGTT, enhancing test sensitivity. Whether use of CGMs 
to evaluate type 2 diabetes risk in free-living youth is 
feasible and acceptable to patients and families is 
unknown. Assessment of CGM with standardized, but 
practical, 
home-based 
glucose 
and 
mixed-meal 
challenges is needed to determine facilitators and barriers 
to use of this technology-driven approach in clinical 
practice. Without advancement in the approach to 
screening for youth-onset T2D, there is ongoing risk of 
failure to understand which individuals are at highest risk 
for complications and could benefit the most from 
intervention early in the disease process.  
Study Objective(s) 
Primary: to determine the feasibility of CGM-based 
type 2 diabetes risk evaluation in youth, as measured by 
adequacy of CGM data capture and nutrition logging 
quality and completion during at-home glucose 
challenge. 
Secondary: to determine the test performance 
characteristics of at-home, CGM-measured glucose 
challenge as compared to a gold-standard laboratory-
based 2-hour OGTT; to determine the acceptability of 

 
 
 
 
 
 
 
 
 
 
vii 
use of CGM for at-home dysglycemia evaluation as an 
alternative to clinical 2-hour OGTT 
Study Design 
 
Prospective observational study 
Subject Population 
Key criteria for Inclusion and 
Exclusion: 
Inclusion Criteria 
1. Any gender, age 8-18 years 
2. Tanner 2 or higher pubertal development 
3. Overweight or obese (BMI ≥85th percentile for 
age/sex, or ≥25 kg/m2 for participants =18 years) 
4. A) No previously documented abnormal HbA1c 
or glucose but at higher risk for T2D based on 
race/ethnicity (Black, Hispanic, Asian, Native 
American, Pacific Islander), diagnosis with 
dyslipidemia, hypertension, polycystic ovary 
syndrome, presence of acanthosis nigricans, or 
first degree relative with T2D (n = 15); or B) 
previously documented (within 6 months) 
HbA1c 5.7-7.0%, fasting glucose ≥100 mg/dL, 
or 2-hour plasma glucose on OGTT of ≥140 
mg/dL (n = 25) 
5. Consent (adult subjects), parental/guardian 
permission (if applicable), assent (if applicable) 
6. Willingness to wear ActiGraph watch and CGM 
continuously for 10 day study duration 
 
Exclusion Criteria 
1. Current or recent (within 1 month) use of 
diabetes-related medication 
2. Current use of hydroxyurea (due to interference 
with CGM) 
3. Known type 1, cystic fibrosis-related, or 
medication-induced diabetes 
4. Potential subject unable to speak or read in 
English  
5.   Severe cognitive impairment 
6. Current or previous pregnancy 
Number Of Subjects  
40 total, all at Children’s Hospital of Pittsburgh 
Study Duration 
Each participant will attend 1 in-person study visits that 
will last 2.5-3 hours, followed by 10 days of continuous 
CGM wear at home. The entire study is expected to last 
approximately 1 year, from July 1, 2022 – June 30, 
2023. 

 
 
 
 
 
 
 
 
 
 
viii 
Study Phases 
  
Screening and recruitment: Potential subjects will be 
identified via review of Endocrinology clinic schedules 
weekly and by using the Research Interest Form 
distributed by Adolescent medicine. After potential 
subjects are identified, they will be contacted along with 
their parents/guardians (as applicable), to screen for 
eligibility. Subjects will be consented and will be 
scheduled for a morning study visit at the Pediatric 
Clinical and Translational Research Center (PCTRC). 
They will be instructed to complete an overnight 10 
hour fast at home prior to the study visit. 
Study Visit 1: Participants will undergo physical 
examination 
by 
a 
pediatric 
endocrinologist, 
anthropometrics, vital signs measurement, questionnaires 
(medical, family, social history), and 2-hour oral glucose 
tolerance test (OGTT). Dexcom G6 Pro (blinded, no data 
visible to participant) CGM will be placed on the 
participant’s abdomen by trained study staff. Participants 
(or their parent) will be registered for text message-based 
surveys and will be instructed on nutrition, activity, and 
sleep logging to be completed during the 10-day CGM 
wear period. Participants will be provided with a wrist-
worn actigraphy device (ActiGraph GT9X Link) to wear 
continuously during the 10-day period for collection.  
10-day Observation Period: Participants will be 
instructed to participate in their typical daily routines, 
with the exception of two at-home challenges: 1) glucose, 
and 2) mixed-meal. The at-home glucose challenge will 
serve as the primary comparison to the laboratory-
measured OGTT. For this challenge, participants will be 
asked to drink the same glucose solution (Trutol) 
consumed as part of the OGTT at PCTRC and provided 
with the appropriate weight-based amount. They will be 
instructed to choose a day between days 3 and 9 of the 
study period during which they will be able to fast for at 
least 10 hours, drink the glucose beverage over the course 
of 5 minutes, and then be inactive for 2 hours. They will 
log the date and time of glucose ingestion. For the at-
home mixed-meal challenge, participants will be asked 
to choose a day between study days 3 and 9, separate 
from the glucose challenge day, during which they will 
be able to fast for at least 10 hours, eat a snack or meal 
with at least 50 grams of carbohydrate as well as fat and 
protein content, and then be inactive for 2 hours. All 
participants 
and families 
will 
be instructed on 

  
 
 
 
  
 
 
 
ix 
determination of carbohydrate content using example 
foods that they typically consume.  
Text message-based surveys: Participants will be sent 
surveys 3 times daily via text message, inquiring about 
food and drink intake, physical activity, and time in bed 
(start/stop times).  
Study completion: On day 10 of CGM wear (or earlier in 
case of discomfort), participants will remove the sensor 
and transmitter at home by simply peeling off the device. 
Transmitter and ActiGraph will be returned to the study 
team by participants using prepaid shipping envelopes or 
in-person if preferred. Upon receipt of the transmitter and 
ActiGraph, participants will receive compensation for 
participation in the study ($100).  
Individual 
interview 
and 
disordered 
eating 
questionnaire: 
Upon completion 
of CGM wear, 
participants, with or without their parents at the discretion 
of the research team, will be invited to participate in a 20-
minute 
semi-structured 
interview 
via 
phone 
or 
videoconferencing platform to assess the acceptability of 
CGM use as an alternative to clinical OGTT for diabetes 
risk assessment. Interviews will be conducted by study 
staff and will be audio-recorded and professionally 
transcribed.  
After completion of the interview, participants will be 
asked to complete a brief, 12-item questionnaire related 
to disordered eating behaviors in the past 28 days. This 
will be completed via REDCap. Participants will be 
allowed to skip questions if they are uncomfortable 
answering. 
Participants will be compensated $15 for completion of 
the interview.  
 
Efficacy Evaluations 
Feasibility and acceptability of CGM with at-home 
glucose challenge as compared to clinical OGTT 
Safety Evaluations 
Adverse events are not anticipated. Ingestion of the 
glucose beverage uncommonly leads to 
nausea/vomiting. Mild skin irritation may result from 
use of adhesives for CGM placement. OGTT evaluation 
may result in recognition and diagnosis of previously 
unknown diabetes; results will be shared with 
participants. Any AEs and SAEs will be reported to IRB 
within the allotted timeframe. 

  
 
 
 
  
 
 
 
x
Statistical And Analytic Plan 
Demographic and clinical characteristics will be 
described using summary statistics, including means, 
standard deviations, medians, and ranges for continuous 
variables, and frequencies for categorical variables. 
Analyses will be conducted using Stata 17 (StataCorp, 
College Station, TX). Raw actigraphy data will be 
processed using GGIR, a package in R: A language and 
environment for statistical computing (R Corp Team, 
Vienna, Austria). The significance level for two-sided 
hypothesis testing will be set at 0.05. 
To assess completeness of CGM data, the number of days 
with adequate CGM data will be divided by 9, omitting 
the first 24 hours due to possible inconsistent 
measurements after initial placement. Feasibility will be 
defined as ≥ 80% (7.2) of days with data. To assess 
completeness of glucose and mixed-meal challenge 
documentation, the number 
of participants who 
document the date and time of glucose and mixed-meal 
ingestion (including mixed-meal content) will be 
determined and divided by the total number of 
participants (40). Feasibility will be defined as ≥80% of 
participants documenting date and time of either the 
glucose challenge, mixed-meal challenge, or both. To 
evaluate test performance characteristics, sensitivity, 
specificity, and positive and negative predictive values of 
glucose on CGM 2 hours after at-home glucose beverage 
ingestion (CGM-2h) to predict OGTT-2h≥140 mg/dL 
will be assessed for various thresholds of CGM-2h. Area 
under the receiver operating characteristic curve (AUC) 
will be determined. An AUC threshold of ≥0.7 will be 
used to define adequate discrimination. Acceptability 
will be rated on a Likert scale (1: completely 
unacceptable, 2: mostly unacceptable, 3: neutral, 4: 
mostly 
acceptable, 
5: 
completely 
acceptable). 
Acceptability will be defined as a mean score for all 
participants of ≥3. Interview transcripts will be reviewed 
by study staff trained in qualitative analysis. Content 
analysis will be used to identify themes and sub-themes. 
DATA AND SAFETY MONITORING 
PLAN 
The study team will be responsible for data management 
and collection and are responsible for the accuracy and 
completeness. Only investigators and study team 
members that have completed appropriate IRB 
training/approval are eligible to collect and work on 
information collected from this study. Data will be 
entered directly into REDCap by the study team or by 

  
 
 
 
  
 
 
 
xi 
participants when responding to surveys. In order to 
guard against disclosure of PHI, each study participant 
will be assigned a unique identification code. The code 
will be kept in a password-protected file on the PI’s 
UPMC-managed secure server.   

 
xii  
 
 
 
 
 
 
 
TABLE 1: SCHEDULE OF STUDY PROCEDURES  
Study Phase 
Screening 
(Phone or 
in-person) 
Study Visit 
(PCTRC) 
Observation 
Period 
(Home) 
Interview 
(Phone) 
Return of 
CGM and 
ActiGraph 
(mail) 
 
 
Study Days 
 
1 
1-10 
Within 4 
weeks after 
Study Visit 
Upon 
completion of 
CGM wear 
Review Inclusion/Exclusion 
Criteria 
X 
X 
 
X 
 
Written Documentation of 
Consent/Assent 
X 
(X if not 
obtained prior) 
 
 
 
Demographics/Medical History 
 
X 
 
 
 
Physical Examination 
 
X 
 
 
 
Vital Signs: BP, HR, RR 
 
X 
 
 
 
Anthropometry 
 
X 
 
 
 
Urine Pregnancy Test 
 
X 
 
 
 
Prior/Concomitant Medications 
 
X 
 
 
 
2-hour OGTT, HbA1c  
 
X 
 
 
 
Place CGM, give ActiGraph to 
wear 
 
X 
 
 
 
Wear CGM, ActiGraph 
 
 
X 
 
 
Respond to surveys   
 
 
X 
 
 
Individual interview,questionnaire 
 
 
 
X 
 
Adverse Event Assessment 
 
 
X 
X 
 
Return CGM, ActiGraph  
 
 
 
 
X 
Upload CGM, Actigraphy data 
 
 
 
 
X 

 
page xiii 
  
 
 
 
FIGURE 1: STUDY DIAGRAM 
 
 
 
 
 

 
  
 
 
 
1 
2 
BACKGROUND INFORMATION AND RATIONALE 
2.1 Introduction 
Youth-onset type 2 diabetes (T2D), an increasingly common and aggressive disease that 
disproportionately impacts racial and ethnic minorities, presents several diagnostic 
challenges. Unlike type 1 diabetes, type 2 diabetes may occur asymptomatically while still 
contributing to complications including nerve damage, blindness, and kidney failure. Early 
identification and targeted lifestyle intervention for those at risk for T2D has proven effective 
in adults.(Knowler, Barrett-Connor et al. 2002) Although similar efficacy data is lacking in 
youth, the rapid loss of glycemic control soon after T2D diagnosis(Group, Zeitler et al. 2012) 
makes early identification an important goal in pediatrics, and risk-based screening has been 
recommended for children for over two decades.(American Diabetes Association Professional 
Practice, American Diabetes Association Professional Practice et al. 2022) However, the 
screening tests currently used in practice, including hemoglobin A1c (HbA1c), fasting 
glucose, and 2-hour oral glucose tolerance test (OGTT), have notable drawbacks. Fasting 
tests, particularly the time-intensive 2-hour OGTT, are often impractical to complete, while 
the non-fasting HbA1c is an indirect measure of glycemia that is unreliable in the setting of 
abnormal hemoglobin or atypical blood cell turnover.  
Real-time continuous glucose monitors (CGM) are promising new tools for risk stratification 
in individuals with dysglycemia. These patient-worn medical devices measure interstitial 
glucose every 5 minutes and are increasingly used in clinical practice for diabetes 
management, particularly for type 1 diabetes. This technology offers glimpses into an 
individual’s everyday life, which may include consumption of carbohydrates in amounts 
larger than that assessed in an OGTT, enhancing test sensitivity. Whether use of CGMs to 
evaluate type 2 diabetes risk in free-living youth is feasible and acceptable to patients and 
families is unknown. Assessment of CGM with standardized, but practical, home-based 
glucose and mixed-meal challenges is needed to determine facilitators and barriers to use of 
this technology-driven approach in clinical practice. Without advancement in the approach to 
screening for youth-onset T2D, there is ongoing risk of failure to understand which individuals 
are at highest risk for complications and could benefit the most from intervention early in the 
disease process.  
The overall objective for this study is to determine whether CGM paired with technology-
driven health behavior data collection is a feasible and acceptable approach to T2D 
screening for youth and their caregivers. The central hypothesis is that CGM, text message-
based surveys, and home-based glucose challenge will allow for accurate classification of 
diabetes risk while providing an acceptable alternative to clinical OGTT for families. 
Previous research has demonstrated the strong correlation between several CGM indices and 
HbA1c or 2-hour glucose on OGTT in youth with obesity and dysglycemia,(Chan, Pyle et 
al. 2015) and home-based glucose challenge with CGM appears promising for use in adults 
across the glycemia spectrum.(Dehghani Zahedani, Shariat Torbaghan et al. 2021) 
Determination of the feasibility and acceptability of CGM with home-based glucose 
challenge in youth at risk for T2D will pave the way for a new screening method that 
minimizes family burden while maximizing data quality and ability to accurately risk-
stratify.  

 
  
 
 
 
2 
2.2 Name and Description of Intervention 
This study will compare laboratory-measured glucose after oral glucose tolerance test to 
CGM-measured glucose after at-home glucose challenge, as well as assess the feasibility 
and acceptability of this approach to T2D risk assessment in youth.  
2.3 Relevant Literature and Data 
Type 2 diabetes (T2D), an obesity-related disease once limited to adults, has become 
increasingly common in youth over the past two decades.(Divers 2020, Lawrence, Divers et 
al. 2021) Prevalence of youth-onset T2D is highest among racial and ethnic minorities, a 
disparity that will widen due to a more rapidly rising incidence in minority youth as compared 
with non-Hispanic white youth.(Mayer-Davis, Lawrence et al. 2017) Youth-onset T2D is 
associated with numerous severe health outcomes, including an 80% cumulative incidence of 
microvascular comorbidities such as kidney, retinal, and nerve disease within 15 years of 
diagnosis.(Group, Bjornstad et al. 2021) Pregnancy outcomes for adolescent and young adult 
women with T2D are incredibly poor, with a 25% rate of pregnancy loss and 33% rate of 
preterm birth.(Group 2021) Due to the severe complications of youth-onset T2D, the 
American Diabetes Association recommends a risk-based screening approach, targeting youth 
ages 10 and older (or earlier if pubertal) with overweight or obesity who have at least one 
additional risk factor including race/ethnicity (African American, Native American, Latino, 
Asian American, Pacific Islander), maternal history of gestational diabetes, family history of 
T2D in a first- or second-degree relative, or signs of insulin resistance or associated condition 
(acanthosis nigricans, hypertension, dyslipidemia, polycystic ovary syndrome, or small-for-
gestational-age birth weight).(American Diabetes Association Professional Practice, 
American Diabetes Association Professional Practice et al. 2022) However, the screening tests 
currently used in practice, including hemoglobin A1c (HbA1c), fasting glucose, and 2-hour 
oral glucose tolerance test (OGTT), have notable drawbacks. Fasting tests, particularly the 
time-intensive 2-hour OGTT, are often impractical to complete, while the non-fasting HbA1c 
is convenient (Lee, Eason et al. 2014) but is an indirect measure of glycemia that is unreliable 
in the setting of abnormal hemoglobin or atypical blood cell turnover and is a more expensive 
test than plasma glucose.(Wu, Kazzi et al. 2013, Vajravelu and Lee 2018)  
Real-time continuous glucose monitors (CGM) are a promising new tool for risk stratification 
in individuals with dysglycemia. These patient-worn medical devices measure interstitial 
glucose every 5 minutes and are increasingly used in clinical practice for diabetes 
management. This technology offers glimpses into an individual’s everyday life, which may 
include consumption of carbohydrates in amounts larger than that assessed in an OGTT, 
enhancing test sensitivity. In an observational study of 98 youth with obesity, prediabetes, or 
T2D who wore CGM for 48 hours, free-living glycemia was highly correlated (r=0.5) with 
both HbA1c and OGTT.(Chan, Pyle et al. 2015) Although this study demonstrated strong 
correlations between CGM indices and traditional testing strategies, it consisted of only 2 days 
of data, without standardized home glucose or mixed-meal challenge. A study in adults across 
the glucose and dysglycemia spectrum, including non-insulin treated T2D, prediabetes, and 
normal glucose, did evaluate home glucose and mixed-meal challenges during 10-day CGM 
wear and demonstrated diabetes-range glucose excursions even in participants with self-
reported prediabetes.(Dehghani Zahedani, Shariat Torbaghan et al. 2021) This study did not 
directly compare home glucose challenge results with laboratory-measured OGTT, however. 

 
  
 
 
 
3 
The potential acceptability and safety of use of CGM among adolescents with obesity as a 
behavior modification tool has been shown in a pilot study evaluating time-limited eating and 
CGM use.(Vidmar, Naguib et al. 2021) To our knowledge, no studies have evaluated home-
based glucose challenges using CGM in adolescents at risk for T2D. If feasible and acceptable, 
this strategy could improve access to critical health evaluations, minimizing patient and family 
burden while providing rich glycemic data to guide treatment decisions. Whether use of 
CGMs to evaluate T2D risk in free-living youth is feasible and acceptable to patients and 
families is unknown. Without advancement in the approach to screening for youth-onset T2D, 
it will remain challenging to accurately determine which individuals are at highest risk for 
complications and could benefit the most from targeted, intensive lifestyle interventions. 
An additional important research question relates to the impact of disordered eating, most 
notably loss-of-control (LOC) eating, on glycemia. Disordered eating, including the 
consumption of objectively large amounts of food in one sitting, is common among youth 
with obesity and type 2 diabetes (TODAY Study Group 2011). The amount of carbohydrate 
and other nutrients consumed in a real-life, non-lab setting may be significantly larger than 
that provided in a standard oral glucose tolerance test, potentially leading to greater 
discrepancy between at-home and lab-based measures of glycemia in youth with disordered 
(LOC) eating than those without this tendency. 
   
2.4 Compliance Statement 
This study will be conducted in full accordance all applicable Children’s Hospital of 
Pittsburgh and University of Pittsburgh Research Policies and Procedures and all applicable 
Federal and state laws and regulations including 45 CFR 46. All episodes of noncompliance 
will be documented. 
The investigators will perform the study in accordance with this protocol, will obtain 
consent and assent, and will report unanticipated problems involving risks to subjects or 
others in accordance with institutional Policies and Procedures and all federal requirements. 
Collection, recording, and reporting of data will be accurate and will ensure the privacy, 
health, and welfare of research subjects during and after the study.  
3 
STUDY OBJECTIVES 
The purpose of the study is to determine the feasibility and acceptability of CGM-based at-
home glucose challenge as an alternative to clinical OGTT for T2D risk assessment in 
youth.   
3.1 Primary Objective  
The primary objective is to determine the feasibility of at-home CGM-based glycemia 
evaluation as measured by adequacy of CGM data capture and nutrition logging quality and 
completion.  
 
3.2 Secondary Objectives  
The secondary objectives are to: 

 
  
 
 
 
4 
• determine the test performance characteristics of at-home, CGM-measured glucose 
challenge as compared to a gold-standard laboratory-based 2-hour OGTT 
• to determine the acceptability of use of CGM for at-home dysglycemia evaluation as 
an alternative to clinical 2-hour OGTT 
 
4 
INVESTIGATIONAL PLAN 
4.1 General Schema of Study Design 
This prospective observational study will include screening by phone or in-person, 
completion of one in-person study visit, completion of 10 days of CGM wear and survey 
completion at home, one at-home glucose challenge and one at-home mixed meal challenge, 
and one phone interview.  
4.1.1 Screening Phase 
Potential subjects will be identified through weekly review of Pediatric Endocrinology and 
Diabetes clinic schedules. In addition, a list of potentially eligible patients will be generated 
via review of a list of patients with diagnosis of prediabetes or obesity and insulin resistance 
from current and previous research conducted by the PI or the PI’s mentor, Dr. Silva 
Arlsanian. The Wellness and Obesity Registry, monitored by Dr. Silva Arslanian, will be 
used to screen for potential subjects as well.The CAYAH RESEARCH INTEREST FORM 
will also be used for recruitment purposes. This is a REDCap form with a survey link that 
will contain questions for adolescents to answer self-screen questions which are non-
sensitive. Center for Adolescent and Young Adult Health (CAYAH) clinical staff will 
manage and distribute this survey. CAYAH clinical research staff will advertise the study to 
the teen. If the teen (age 13 or older) indicates interest in the study by viewing the study 
advertisement within the CAYAH RESEARCH INTEREST FORM, they will provide their 
contact information to the CAYAH clinical research staff who will then share it with the 
study team.  Medical records of potential subjects will be screened by the study team using 
the protocol inclusion and exclusion criteria. Those who appear to meet the criteria will be 
approached by a member of the study team by phone, email, or in-person and asked if they 
would like to hear about the study. Subjects and/or their parent/guardian will provide 
demographic, social, and medical information about themselves, their child, or family (as 
applicable) to confirm eligibility.  
4.1.2 Study Visit 
After study procedures are reviewed and questions answered, written informed consent and 
assent (participants<18) will be obtained if not already obtained electronically via REDCap. 
Participants will arrive after overnight fast (minimum 10 hours) and will undergo physical 
examination by a pediatric endocrinologist as well as anthropometrics, vital sign 
measurement, questionnaires (medical, family, social history), and 2-hour OGTT performed 
according to American Diabetes Association criteria.(American Diabetes Association 
Professional Practice, American Diabetes Association Professional Practice et al. 2022) After 
baseline (time 0) venous blood sample, participants will ingest glucose solution (1.75 g/kg 
body weight, max 75g) within 5 minutes or less. Additional venous blood samples will be 
obtained at timed intervals after ingestion to determine plasma glucose, insulin, and c-peptide 

 
  
 
 
 
5 
(30, 60, 90, 120 min) . HbA1c will also be measured (one venous blood sample). During 
OGTT, Dexcom G6 Pro (blinded, no data visible to participant) CGM will be placed on the 
participant’s abdomen by study staff trained in CGM placement. Participants will be assigned 
a unique study ID for use with Dexcom and survey collection. Participants (or their parent if 
the participant does not have a phone with text messaging capability) will also be registered 
for text message-based surveys via Mosio, a text messaging platform for clinical research, and 
will be instructed on nutrition, activity, and sleep logging to be completed during the 10-day 
CGM wear period. Paper logbooks will be provided for use in case of technical difficulties 
with texts. Participants will be provided with a wrist-worn actigraphy device (ActiGraph 
GT9X Link) to wear continuously during the 10-day period for collection of objectively 
measured activity and sleep data to define periods of eating, overnight fasting, and exercise.  
4.1.3 Observation Period 
Participants will be instructed to participate in their typical daily routines, with the exception 
of two at-home challenges: 1) glucose, and 2) mixed-meal. The at-home glucose challenge 
will serve as the primary comparison to the laboratory-measured OGTT. For this challenge, 
participants will be asked to drink the same glucose solution (Trutol) consumed as part of 
the OGTT at PCTRC and provided with the appropriate weight-based amount. They will be 
instructed to choose a day between days 3 and 9 of the study period during which they will 
be able to fast for at least 10 hours, drink the glucose beverage, and then be inactive for 2 
hours. They will log the date and time of glucose ingestion. For the at-home mixed-meal 
challenge, participants will be asked to choose a day between study days 3 and 9, separate 
from the glucose challenge day, during which they will be able to fast for at least 10 hours, 
eat a snack or meal with at least 50 grams of carbohydrate as well as fat and protein content, 
and then be inactive for 2 hours. All participants and families will be instructed on 
determination of carbohydrate content using example foods that they typically consume. 
Participants will receive $20 for travel to the study visit, loaded onto a university payment 
card. 
Text message-based surveys and actigraphy: Participants will be sent surveys 3 times daily 
via text message, inquiring about food and drink intake, physical activity, and time in bed 
(start/stop times). Survey responses will be collected via Mosio and entered in Research 
Electronic Data Capture (REDCap), a secure, web-based application for clinical research data 
collection. Branching logic will be used in REDCap so that participants will only need to 
provide detail for relevant activities each time. As an incentive for ActiGraph wear, 
participants will earn an additional $20 if the ActiGraph device is worn for at least 8/10 days.  
Study completion: On day 10 of CGM wear (or earlier in case of discomfort), participants will 
remove the sensor and transmitter at home by simply peeling off the device. Transmitter and 
ActiGraph will be returned to the study team by participants using prepaid shipping envelopes 
or in-person if preferred. Upon receipt of the transmitter and ActiGraph, participants will 
receive compensation for participation in the study ($100).  
4.1.4 Individual Interview and Disordered Eating Questionnaire 
Upon completion of CGM wear, youth participants, with or without their parents at the 
discretion of the research team, will be invited to participate in a 20-minute semi-structured 
interview via phone or videoconferencing platform to assess the acceptability of CGM use 
as an alternative to clinical OGTT for diabetes risk assessment. Interviews will also be used 

 
  
 
 
 
6 
to elicit barriers and facilitators to diabetes evaluation and follow up for diabetes risk. 
Interviews will be conducted by study staff and will be audio-recorded and professionally 
transcribed.  
After completion of the interview, participants will be asked to complete a brief, 12-item 
questionnaire related to disordered eating behaviors in the past 28 days. This will be 
completed via REDCap. Participants will be allowed to skip questions if they are 
uncomfortable answering. 
Participants will be compensated $15 for completion of the interview. 
4.1.5 Data Collection 
CGM data extraction: Upon receipt of a participant transmitter, study staff will use a Dexcom 
G6 Pro receiver to upload the data to Clarity, a cloud-based software for data visualization 
and extraction. Glucose values and timestamps will be downloaded via CSV file to the 
principal investigator’s secure UPMC shared drive for analysis.  
Actigraphy data extraction: ActiLife 6 desktop software will be used to extract actigraphy 
data from returned ActiGraph GT9X Link devices. Automatically-detected sleep periods will 
be cross-checked with participant-reported start/end times in bed.  
 
4.2 Study Duration, Enrollment and Number of Sites 
4.2.1 Duration of Subject Study Participation 
The study visit is expected to take approximately 2.5-3 hours. CGM will be worn for 10 
days, beginning the day of the study visit. The phone interview is expected to take 
approximately 30 minutes. The phone call will take place no more than 4 weeks after the 
study visit.  
4.2.2 Total Number of Study Sites/Total Number of Subjects Projected 
This study will be conducted at the Children’s Hospital of Pittsburgh. A maximum of 40 
subjects will be included. 
4.3 Study Population 
We will not restrict enrollment based on gender or age within the eligible age group.  
We plan to enroll only English-speaking patients. 
4.3.1 Inclusion Criteria  
1. Any gender, age 8-18 years 
2. Tanner 2 or higher pubertal development 
3. Overweight or obese (BMI ≥85th percentile for age/sex, or ≥25 kg/m2 for participants 
=18 years) 
4. A) No previously documented abnormal HbA1c or glucose but at higher risk for T2D 
based on race/ethnicity (Black, Hispanic, Asian, Native American, Pacific Islander), 

 
  
 
 
 
7 
diagnosis with dyslipidemia, hypertension, polycystic ovary syndrome, presence of 
acanthosis nigricans, or first degree relative with T2D (n = 15); or B) previously 
documented (within 6 months) HbA1c 5.7-7.0%, fasting glucose ≥100 mg/dL, or 2-
hour plasma glucose on OGTT of ≥140 mg/dL (n = 25) 
5. Consent (adult subjects), parental/guardian permission (if applicable), assent (if 
applicable) 
6. Willingness to wear ActiGraph watch and CGM continuously for 10 day study 
duration 
4.3.2 Exclusion Criteria  
1. Current or recent (within 1 month) use of diabetes- or obesity-related medication 
2. Current use of hydroxyurea (due to interference with CGM) 
3. Known type 1, cystic fibrosis-related, or medication-induced diabetes 
4. Potential subject unable to speak or read in English  
5.   Severe cognitive impairment 
6. Current or previous pregnancy 
 
Subjects that do not meet all of the enrollment criteria may not be enrolled. Any violations of 
these criteria must be reported in accordance with IRB Policies and Procedures.  
 
5 
STUDY PROCEDURES 
5.1 Phone screening 
• Medical Record Review 
• Brief study overview: 5 minutes 
• Consent/HIPAA Authorization: 5-10 minutes/as long as needed for full 
comprehension of study involvement (if not already obtained electronically via 
REDCap) 
• Screening questionnaire: 5 minutes 
• Overview of 12-hour overnight fast and upcoming study visit: 5 minutes 
5.2 Study Visit  
• Vital signs (heart rate, blood pressure): 5 minutes 
• Urine pregnancy test (all females): 3 minutes 

 
  
 
 
 
8 
• Height, weight, waist and hip circumference: 5 minutes 
• Focused physical exam, including pubertal status: 5 minutes 
• Fasting 2-hour oral glucose tolerance test: 120 minutes 
• Medical, surgical, family, social history: 10 minutes (during OGTT) 
• Provide ActiGraph device, instruct on use: 5 minutes (during OGTT) 
• Place CGM on abdomen, instruct on use: 5 minutes (during OGTT) 
• Review instructions for glucose and mixed meal challenge, including food label 
interpretation for carbohydrate content: 10 minutes (during OGTT) 
• Enroll in text messaging platform, instruct about survey completion: 5 minutes 
(during OGTT) 
• Provide addressed, pre-paid shipping envelope to return CGM, ActiGraph 
5.3 Observation Period, Days 1-10 
5.3.1 Non-Challenge Days:  
• Participant wears CGM, ActiGraph continuously 
• Text messages sent 3 times daily (10 AM, 2 PM, 8 PM) to collect nutrition, physical 
activity, sleep records 
• No changes to routine diet or activity 
5.3.2 Glucose Challenge: day of participant’s choice between Days 3 and 9   
• Participant wears CGM, ActiGraph continuously 
• After minimum 10 hours of fasting overnight, participant drinks study-provided 
glucose beverage without any additional food or drink and remains as inactive as 
possible for 2 hours 
• Text messages sent 3 times daily (10 AM, 2 PM, 8 PM) to collect nutrition, physical 
activity, sleep records 
o At next available survey time, participant indicates time that glucose 
beverage was consumed (start and finish times) 
5.3.3 Mixed Meal Challenge: day of participant’s choice between Days 3 and 9     
• Participant wears CGM, ActiGraph continuously 
• After minimum 10 hours of fasting overnight, participant eats food item of their 
choice that contains at least 50 grams carbohydrate as well as fat and protein, without  
any additional food or drink, and remains as inactive as possible for 2 hours 
• Text messages sent 3 times daily (10 AM, 2 PM, 8 PM) to collect nutrition, physical 
activity, sleep records 

 
  
 
 
 
9 
o At next available survey time, participant indicates time that mixed meal 
challenge was completed, as well as food item chosen and nutritional content 
(amount, and carbohydrates, fat, protein per serving) 
5.3.4 Removal and Return of CGM and ActiGraph: Day 10 
• Midday on the 10th day of CGM wear, participants will remove CGM by painlessly 
peeling off the adhesive and device 
• Sensor and transmitter will be placed in a Ziploc bag and placed in the prepaid, 
addressed envelope for return 
• ActiGraph will be removed from wrist and placed with CGM in envelope 
• Envelope will be sent to study team by participant 
• Compensation will be provided to participants upon receipt of the CGM and 
ActiGraph 
5.4 Individual Interview and Disordered Eating Questionnaire: any time 
between Day 10 of Observation Period and 1 month after Study Visit 
• Participants (ages 15-18) or their parents (for participants ages 8-14) will be invited 
to participate in a 30-minute semi-structured individual interview via phone or 
videoconferencing platform to assess the acceptability of CGM use as an alternative 
to clinical OGTT for diabetes risk assessment.  
• Participants will be asked to complete a brief, 12-item questionnaire related to 
disordered eating behaviors in the past 28 days. This will be completed via REDCap. 
Participants will be allowed to skip questions if they are uncomfortable answering 
• Participants will be compensated $15 for completion of the interview. 
5.5 CGM, ActiGraph Data Extraction 
• Dexcom G6 Pro receiver will be used to transfer CGM sensor data to Dexcom 
Clarity (https://clarity.dexcom.com/professional/) 
• ActiGraph data will be uploaded from the device using ActiLife software on the PI’s 
UPMC desktop computer 
.  
5.6 Subject Completion/Withdrawal 
Subjects may withdraw from the study at any time without prejudice to their care. They may 
also be discontinued from the study at the discretion of the Investigator for lack of adherence 
to study treatment or visit schedules, AEs, or due to adherence to study treatment or visit 
schedules. The Investigator may also withdraw subjects who violate the study plan, or to 
protect the subject for reasons of safety or for administrative reasons.  It will be documented 
whether or not each subject completes the clinical study. If the Investigator becomes aware 
of any serious, related adverse events after the subject completes or withdraws from the 
study, they will be recorded in the source documents and on the case report form (CRF) on 
REDCap. 

 
  
 
 
 
10 
CGM, ActiGraph, questionnaire, and clinical data obtained prior to subject withdrawal will 
be retained. 
5.6.1 Early Termination Procedures 
Subjects who withdraw from the study will be asked to complete the interview to assess 
reasons for early termination and will be asked to return the CGM and ActiGraph device via 
the prepaid envelope. Full compensation will still be provided upon receipt of the devices.  
 
 

 
  
 
 
 
11 
6 
STUDY EVALUATIONS AND MEASUREMENTS 
6.1 Screening and Monitoring Evaluations and Measurements 
6.1.1 Medical Record Review 
Participants will be interviewed regarding their medical history. To ensure that no major 
items are missed and to clarify interview answers, the study team will review participant 
electronic medical records prior to and after the participant interview to confirm the 
following: 
• Date of birth 
• Birth history (gestational age, birth weight, complications during pregnancy) 
• Anthropometrics (weight, height, BMI) 
• Medications 
• List of medical problems, especially as they relate to inclusion and exclusion criteria 
• Demographic data including race, ethnicity, gender, and insurance type 
• Endocrine-related diagnoses, including: insulin resistance, prediabetes, impaired 
glucose tolerance, impaired fasting glucose, elevated hemoglobin A1c, diabetes 
mellitus, and polycystic ovary syndrome  
• History of attendance at an obesity clinic  
• History of bariatric surgery 
• Diabetes-related labs, including: plasma and point-of-care glucose, hemoglobin A1c, 
and insulin 
• History of non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, elevated 
ALT or AST, or other known liver disease 
6.1.2 Physical Examination 
A study physician (pediatric endocrinologist) will review with the parent and child the 
child’s current and past medical history, a review of systems, and family history (with 
particular attention to cardiovascular disease and diabetes). A focused physical examination 
will be conducted, including measurement of height, weight, waist circumference, hip 
circumference, pubertal staging, and pertinent physical findings associated with insulin 
resistance, including the presence of acanthosis nigricans, which will be recorded on a 
standardized form.  Investigators will verify that the patient has been fasting for a minimum 
of 10 hours.  
 

 
  
 
 
 
12 
6.1.3 Vital Signs 
• Blood pressure (BP) will be recorded while the subject is sitting down by the nursing 
staff. BP will be measured by auscultation three times, after a five minute rest in a 
quiet area with the subject in a seated position; the average of the 2nd and 3rd 
measurements will be used. 
• Pulse and respiratory rate will be measured by nursing staff 
6.1.4 Laboratory Evaluations  
6.1.4.1 Table: Clinical Laboratory Tests  
Category 
Tests 
Biomarkers of glucose 
metabolism 
Hemoglobin A1c, plasma glucose, insulin, c-peptide 
 
 
 
6.1.4.2 Pregnancy Testing 
A urine pregnancy test will be performed for all female subjects at baseline. A positive 
pregnancy result will be disclosed to the participant only. Pregnancy results will be 
disclosed to the parent/guardian if the subject gives the investigators permission. Subjects 
found to be pregnant during the visit will not be able to enroll in this study. The 
investigators will counsel the subject and guide them to seek the appropriate care. 
6.1.5 Medical History, Family History, Social History Questionnaire  
Will include past medical history, 1st and 2nd degree family history of diabetes, dyslipidemia, 
cardiovascular disease, and socioeconomic status questions. Social history will include 
questions to understand predictors of acceptability of the intervention, including 
parent/guardian’s employment (hours worked, flexibility of hours), household income, 
approximate travel time to UPMC Children’s Hospital of Pittsburgh from their home, child’s 
school start time, number of missed days of school this year related to medical appointments 
or assessments, child’s school performance (excellent, average, below average, failing), 
household size (number of adults, number of children), insurance type 
(commercial/government), and use of government assistance (e.g. SNAP, WIC, public 
housing).  
6.1.6 Interview and Disordered Eating Questionnaire 
Semi-structured individual interviews will be conducted by study staff after the observation 
period to evaluate acceptability of use of CGM for diabetes risk assessment, including 
barriers and facilitators to this approach. Interviews will be audiorecorded and then 
professionally transcribed for qualitative analysis using NVivo software.  
The disordered eating questionnaire includes 12 questions that inquire about the feeling of 
“loss of control” when eating. This questionnaire does not have a validated threshold for 
normal versus abnormal and is not in clinical use in its form in this study.  

 
  
 
 
 
13 
 
 
6.2 Efficacy Evaluations  
CGM data completeness (data available for >=80% requested days worn), nutrition logging 
quality and completion (>=80% of participants documenting date and time of glucose 
challenge, mixed meal challenge, or both), and acceptability (mean score >=3, or “neutral” 
for all participants) will be used to determine feasibility and acceptability of this approach.  
6.3 Safety Evaluations  
Participants will be fasting for a minimum of 10 hours prior to the study visit. This may 
cause hunger pangs, upset stomach, headache, or light-headedness. If the participant shows 
any signs of clinical instability or definitively decides to discontinue participation, the study 
visit will be ended. 
The patient will be notified of any clinically relevant abnormal test result(s) performed. It will 
be recommended that results, especially abnormal results, be discussed by the guardian with 
the participant’s primary care physician.  

 
  
 
 
 
14 
7 
STATISTICAL CONSIDERATIONS 
7.1 Primary Endpoint 
We will determine the completeness of CGM data capture and adequacy of nutrition logs for 
evaluation of at-home glucose challenge.  
7.2 Secondary Endpoints 
Secondary endpoints include test performance characteristics of at-home CGM-measured 
glucose challenge as compared with gold-standard laboratory-based 2-hour OGTT; 
acceptability of use of CGM for at-home dysglycemia evaluation as an alternative to 2-hour 
lab-based OGTT.  
7.3 Control of Bias and Confounding 
Potentially eligible subjects will be stratified by sex and age (8-14, 15-18), and an equal 
number of participants will be contacted per group until recruitment goals are reached or all 
potentially eligible subjects in a category are enrolled or decline to participate. 
Multivariable models will adjust for covariates including age, sex, race, ethnicity, and 
anthropometrics (e.g. BMI-Z).  
 
7.4 Statistical Methods 
7.4.1 Analysis of Primary and Secondary Outcomes of Interest 
Primary objective: Determine the feasibility of at-home, CGM-based glycemia evaluation as 
measured by adequacy of CGM data capture and nutrition logging quality and completion on 
days of at-home glucose and mixed-meal challenge.  
H1a: Complete CGM data will be available for ≥ 80% of requested days worn: The number 
of days with adequate CGM data will be divided by 9, omitting the first 24 hours due to 
possible inconsistent measurements after initial placement. Feasibility will be defined as ≥ 
80% (7.2) of days with data. 
H1b: Documentation of glucose and mixed-meal challenge will be complete and adequate for 
analysis for ≥80% of participants: The number of participants who document the date and 
time of glucose and mixed-meal ingestion (including mixed-meal content) will be determined 
and divided by the total number of participants. Feasibility will be defined as ≥80% of 
participants documenting date and time of either the glucose challenge, mixed-meal challenge, 
or both.  
Secondary objective: Determine the test performance characteristics of at-home, CGM-
measured glucose challenge with laboratory-based 2-hour OGTT.  
H2: CGM-measured glucose 2 hours and 5 minutes after standardized glucose ingestion will 
have adequate discrimination of normal (<140 mg/dL) versus dysglycemic (≥140 mg/dL) 2-
hour OGTT glucose, as assessed by area under the receiver operating characteristic curve ≥ 
0.7: Using participant logs via text message survey or paper-based logs, date and time of home 
glucose challenge will be determined and labeled in CGM data. A time point 2 hours and 5 

 
  
 
 
 
15 
minutes later (accounting for lag due to interstitial measurement)(Wadwa, Laffel et al. 2018) 
(CGM-2h) will serve as the comparison to the 2-hour glucose during OGTT obtained at the 
study visit (OGTT-2h). Sensitivity, specificity, and positive and negative predictive values of 
CGM-2h to predict OGTT-2h≥140 mg/dL will be assessed for various thresholds of CGM-
2h. Area under the receiver operating characteristic curve (AUC) will be determined. An AUC 
threshold of ≥0.7 will be used to define adequate discrimination. The same analysis will be 
repeated for the comparison of baseline CGM glucose (at time of glucose ingestion) to fasting 
glucose on OGTT, using a fasting glucose threshold of ≥100 mg/dL to define dysglycemia. 
Finally, correlation analyses (Spearman or Pearson depending on distribution) will be 
performed to further explore the relationship between CGM indices obtained during at-home 
glucose challenge (e.g., baseline, peak, mean glucose) and both laboratory-measured HbA1c 
and plasma glucose during OGTT. Correlations will be examined across subgroups such as 
lower versus higher ActiGraph-measured physical activity level and self-reported 
carbohydrate intake on the day prior to at-home glucose challenge, age, pubertal stage, and 
body mass index. 
7.4.2 Qualitative analysis 
After the completion of individual interviews, recordings will be transcribed. Transcripts 
will be analyzed in NVivo software, using directed content analysis techniques (Merriam 
and Tisdell 2016) to identify and organize relevant themes. Codes and coding rules for a 
codebook will be established by the PI and study staff based on the interview guide and 
transcripts. When the codebook is established, at least two study staff will independently 
code transcripts to identify themes and sub-themes, resolving disagreements in coding 
through discussion. Themes will be summarized and compared across demographic groups 
(e.g. sex, age, race/ethnicity), activity level (high/low), and sleep duration (longer/shorter). 
Acceptability of the use of CGM for T2D risk evaluation at home will be rated on a Likert 
scale (1: completely unacceptable, 2: mostly unacceptable, 3: neutral, 4: mostly acceptable, 
5: completely acceptable). Acceptability will be defined as a mean score for all participants 
of ≥3. 
7.4.3 Exploratory analyses 
The analyses for at-home glucose challenge described above will be repeated to evaluate the 
test performance of at-home mixed-meal challenge in comparison to 2-hour OGTT. In 
addition, CGM metrics such as average, area under the curve, and peak glucose as well as 
coefficient of variation will be compared for days of CGM wear without glucose or mixed-
meal challenge versus challenge days to assess the difference in glucose trends of typical 
daily life versus those artificially imposed by testing.  
An additional exploratory analysis will use responses from the disordered eating 
questionnaire to assess whether correlations between OGTT and CGM-measured glycemia 
differ between youth with higher versus lower self-report of loss-of-control eating. 
 
7.4.4 Missing Data 
The CGM measures interstitial glucose every 5 minutes, but glucose data may be missing 
due to signal disruption or mechanical dislodgment. Periods of missing data for more than 

 
  
 
 
 
16 
20 minutes will not be replaced. For data gaps of up to 20 minutes, the two glucose values 
preceding and following the missing period will be averaged and used to replace the missing 
data. 
7.5 
Sample Size and Power 
The sample size for this pilot study balances feasibility with the likelihood of obtaining 
meaningful results for future studies. Assuming 20% drop-out or incomplete data, a sample 
size of 40 should lead to 32 evaluable subjects. This will allow for subgroup analyses, 
including by sex and physical activity strata (high versus low). This study will include 
nearly twice as many participants with known dysglycemia (or more if previously 
undiagnosed) as those without in order to maximize the ability to compare impaired glucose 
tolerance and abnormal CGM-measured glucose trends. 
 

 
  
 
 
 
17 
8 
SAFETY MANAGEMENT 
8.1 Clinical Adverse Events 
Clinical adverse events (AEs) will be monitored throughout the study.  
8.2 Adverse Event Reporting 
Since the study procedures are not greater than minimal risk, serious adverse events (SAEs) 
are not expected. If any unanticipated problems related to the research involving risks to 
subjects or others happen during the course of this study (including SAEs) they will be 
reported to the IRB in accordance with institutional guidelines. AEs that are not serious but 
that are notable and could involve risks to subjects will be summarized in narrative or other 
format and submitted to the IRB at the time of continuing review. 
The relationship of each SAE to the study intervention will be characterized using one of the 
following terms in accordance with IRB Guidelines: definitely, probably, possibly, unlikely 
or unrelated.  
8.3 IRB/IEC Notification of SAEs and Other Unanticipated Problems 
The Investigator will promptly notify the IRB of all on-site unanticipated, serious Adverse 
Events that are related to the research activity. Other unanticipated problems related to the 
research involving risk to subjects or others will also be reported promptly. Written reports 
will be filed using the electronic IRB system and in accordance with the timeline below. 
External SAEs that are both unexpected and related to the study intervention will be 
reported promptly after the investigator receives the report.   
Type of Unanticipated Problem 
Initial 
Notification  
(Phone, 
Email, Fax) 
Written Report 
Internal (on-site) SAEs 
Death or Life Threatening  
24 hours 
Within 2 calendar days 
Internal (on-site) SAEs 
All other SAEs 
7 days 
Within 7 business days 
Unanticipated Problems Related to Research 
7 days  
Within 7 business days 
All other AEs 
N/A 
Brief Summary of important AEs may 
be reported at time of continuing review 
8.3.1 Follow-up report 
If an SAE has not resolved at the time of the initial report and new information arises that 
changes the investigator’s assessment of the event, a follow-up report including all relevant 
new or reassessed information (e.g., concomitant medication, medical history) will be 
submitted to the IRB. The investigator will be responsible for ensuring that all SAE are 
followed until either resolved or stable.  
8.4 Investigator Reporting of a Serious Adverse Event to Sponsor 
Reporting will be consistent with National Institutes of Health requirements. 

 
  
 
 
 
18 
8.5 Medical Emergencies 
Medical emergencies that might develop during the course of the study at PCTRC will be 
referred to the CHP emergency room. Medical emergencies that might develop during the 
course of the study during the at-home intervention will be referred to local emergency 
medical services.  
 

 
  
 
 
 
19 
9 
STUDY ADMINISTRATION 
9.1 Data Collection and Management 
The PI is responsible for the accuracy and completeness of data collection and management. 
The PI may designate qualified individual(s) to collect data and manage data. Only 
investigators and research staff that have completed appropriate IRB training and approval 
and are listed on the IRB approved protocol are eligible to collect and work on information 
from the study. Future studies that may use patients or data collected from this study must 
have separate approved IRB protocols and consent forms, if applicable.  
 
REDCap Case Report Forms (CRF): REDCap CRFs will be created by the study team for 
data capture. REDCap is a secure web-based data management software designed by 
Vanderbilt University investigators. Study data will be entered through intelligent REDCap 
forms that adapt to data content, and include built-in eror checks to trap out-of-range or 
inconsistent entries into the central database. Original data will be recorded directly into 
CRFs by the study coordinator or a study investigator after consent is documented. Copies 
of laboratory, physical exam, anthropometric, and questionnaire responses will be received 
through the electronic medical record or through secured email. This information also will 
be recorded into CRFs in REDCap. The password to log into REDCap will be unique to 
each member of the study team. REDCap will also be used to collect disordered eating 
questionnaire responses. 
 
Dexcom G6 Pro Data: Dexcom Clarity for Health (https://clarity.dexcom.com/professional/) 
will be used to upload CGM data. Only study IDs will be used, without identifiable patient 
information. A separate “clinic” will be created for this research project on the website, with 
a separate login created for each study team member. The PI and primary research 
coordinator will have Administrator privileges for data access and uploads; additional study 
staff will be added for view or upload only, without editing priviliges.  
ActiGraph GT9X Link Data: ActiLife 6 software will be used to upload and analyze 
anonymized actigraphy data. This software will be on the PI’s UPMC desktop computer, 
and uploaded data will be saved to the PI’s UPMC secure shared drive.  
Text Message-Based Survey Data: Following enrollment, study staff will obtain the phone 
number for the participant or participant parent’s text message-enabled cellphone in order to 
send and receive text message based nutrition, activity, and sleep surveys. No PHI will be 
shared with the text message platform Mosio.  
 
Interview Data: Written data collected during the interview will be stored in a secure file 
cabinet in the PI’s office. Only the research team will have access to interview notes, which 
will be destroyed after a minimum of 7 years after completion of the study. Interviews will 
also be audio-recorded. Audio recordings will be kept as digital files and kept on the PI’s 
password-protected institutional shared drive. Recordings will be destroyed after the 
recordings are transcribed and qualitative analysis is complete. 
 

 
  
 
 
 
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Participant Recruitment Log: This password-protected Microsoft Excel file, saved on the 
PI’s institutional shared drive will include patient identifying information necessary for 
registration, enrollment, and follow-up. Following enrollment, this document will be used to 
maintain a log of enrolled patients. For patients who are not enrolled, patient-identifying 
information will be destroyed. A non-identifiable list of patients that were not enrolled will 
be retained for the purpose of calculating response rate.  
 
Consent Forms: Electronic copies of the consent forms will be stored in a password-
protected folder on the PI’s shared drive. Participants will be emailed their signed consent 
form. If a participant turns 18 during the study, consent will be re-obtained electronically via 
REDCap. 
 
Anonymization: Data will be extracted from REDCap, Dexcom Clarity, and ActiLife 
software and downloaded onto the PI’s secure UPMC shared drive. Datasets will be stripped 
of all identifiers and individuals will be referred to by their study ID. The study ID will also 
be used on all analytical files. 
 
9.2 Confidentiality 
All data and records generated during this study will be kept confidential in accordance with 
institutional policies and on HIPPA subject privacy. The investigators/study team 
members/site personnel will not use such data and records for any purpose other than for 
conducting the study. 
As a way to minimize the chance of PHI (protected health information) from being 
disclosed, a unique identification code will be used for each participant. Specific keys will 
be saved in an encrypted format on the PI’s secure institutional shared drive.   
Participants will not be identified by name/PHI on any publications that result from this 
research. 
The information collected as part of this study will be kept for 7 years after study 
completion. At that time, the information collected will be destroyed or all identifiable 
information will be removed. All keys will be destroyed at this time, as well. No identifiable 
data will be used for future studies without first obtaining IRB approval. 
9.3 Regulatory and Ethical Considerations 
9.3.1 Data and Safety Monitoring Plan 
Due to the minimal risk involved in the investigation, a Data and Safety Monitoring Board 
(DSMB) is not applicable. Study data will be carefully monitored by the PI. The PI will 
provide weekly supervision to a trained clinical research coordinator who will be involved in 
data collection. The study team will monitor and track collection of all study data. The team 
will additionally track all protocol deviations and adverse events and will report these to the 
IRB, in accordance with reporting guidelines.  

 
  
 
 
 
21 
9.3.2 Risk Assessment 
Study participation poses no more than minimal risk. Expected risks by procedure are as 
follows: 
Phlebotomy and IV insertion: The blood volume collected will be approximately 18 mL. 
The blood volume removal is much less than the maximum blood volume removal per 8-
week period recommended by OHRP (children < 7 ml/kg over 6 weeks). IV insertion and 
phlebotomy will be done by trained PCTRC nurses. There is a risk of bruising and 
discomfort at the venipuncture site. Blood draw may result in temporary discomfort from 
needle stick, bruising, fainting, weakness, and rarely an infection at the site. To minimize 
discomfort, a topical numbing cream or spray will be offered. Slight swelling of the skin in 
response to the numbing medicine may occur in approximately half of all individuals. This 
goes away within about 4 hours in most cases. 
Overnight Fast: Fasting may cause hunger pangs, upset stomach, headache, or light-
headedness. However, the requested fasting period is no longer than usual for most 
individuals, and none of the participants will be taking medications that would place them at 
risk for hypoglycemia. 
Anthropometric measurements and pubertal status: Exam poses minimal risks. The 
anthropometric assessment involves measurements of height, weight, and circumferences. 
Some individuals are uncomfortable with physical examinations. For this reason, during the 
encounter each step will be explained to the participant explicitly. Drapes and other barriers 
will be used if they are required to disrobe during the exam. The exam will be performed by 
staff experienced in obtaining measurements in children at all levels of cognitive ability. 
The measurements are obtained in a private room. The parent is permitted to stay with the 
child if it increases their comfort with the exam. 
 
The puberty assessment will be performed by a pediatric endocrinologist in a private 
setting. The procedure will be explained to the child in advance, and the parent is permitted 
to be present if preferred by the child. The exam is performed by highly experienced 
personnel who are familiar with minimizing distress associated with the exam. 
Blood pressure measurement by auscultation: Procedure may cause temporary 
numbness/tingling in the arm. Blood pressure will be obtained by trained PCTRC nurses.  
Oral glucose tolerance test (OGTT) and at-home glucose challenge: The risks associated 
with the OGTT are the same as those for having blood drawn as described above. The 
OGTT is safe and is used clinically in children and adults of all ages. Glucose is a normal 
nutrient found in many different foods. About one out in ten people have mild nausea or an 
upset stomach with the glucose (sugar) drink that is given during the OGTT. This can be 
minimized by drinking the sugar drink slowly over 5 minutes.  Rarely, some people 
experience a mild low blood sugar reaction (symptoms like nervousness or sweating) at the 
end of the test. Participants will be offered a snack to guard against this from occurring. 
At-home mixed meal challenge: Participants are at no greater risk than usual when they 
consume foods of choice at home. Examples of foods that would satisfy the requirement of 
50g carbohydrate with fat and protein include: 1) 1 banana (27g carbs) and 2 slices of bread 

 
  
 
 
 
22 
with butter or peanut butter (30g carbs); 2) 1.5 cup Honey Bunches of Oats cereal (35g 
carbs) with 1 cup soy milk (15g carbs); 3) 8 oz strawberry yogurt (31g carbs) with 1 cup of 
fresh blueberries (21g carbs) or 1 medium apple (25g carbs). 
 
Wearing Dexcom G6 Pro device for 10 days: The primary risks with Dexcom G6 Pro 
wear include skin irritation due to adhesive; bleeding, pain or infection at insertion site; and 
remote chance of sensor wire breakage. Skin irritation is common among children with type 
1 diabetes (approximately 40-50%), but is significantly more common among individuals 
who have been using CGM (including removing and replacing) for more than 1 year (OR 
0.3, versus less than 1 year) and is most frequently described as “eczema” (35%) or “dry 
wound” (8-14%).(Berg, Olsen et al. 2018)  To minimize risk of irritation or poor adhesion, 
participants will be asked to refrain from using insect repellent, sunscreen, perfume, or 
lotion on their abdominal skin. To minimize risk of insertion complications, only trained 
study staff will place CGM on participants. Staff will clean and dry hands, then put on 
gloves before insertion. The insertion site will be cleaned with alcohol wipes, and device 
inserted after the skin is dry. The device will be placed away from waistbands, scarring, 
tattoos, irritation, or bones (such as hip bone). To minimize risk of sensor wire breakage 
upon removal, participants will be instructed on safe removal technique via a Dexcom-
created video as well as explanation by study staff. Sterile broken or detached sensor wires 
pose minimal medical risk. Participants will be encouraged to call the study team with any 
concerns as soon as possible and informed that they may remove the device at any time if 
needed. If there is concern that the sensor wire has broken off under the skin, participants 
will be advised to not remove it, but to contact the study team. They may also contact 
Dexcom’s 24/7 Technical Support at 1-844-607-8398. Participants may require professional 
medical help if sensor wire is retained in skin, particularly if they have symptoms of 
infection or inflammation at the insertion site.  
Participants will be asked to not undergo magnetic resonance imaging (MRI), computed 
tomography (CT), or diathermy while wearing CGM due to reading inaccuracies that may 
result from magnetic fields or heat.  
Wearing an ActiGraph GT9X physical activity and sleeper tracker on wrist: 
Participants may experience discomfort or rash related to wearing the device. Participants 
will be allowed to remove the device at any time if needed due to discomfort or rash. 
Interview and disordered eating questionnaire: Potential risks include momentary 
embarrassment or discomfort as well as breach of privacy and confidentiality. Participants 
may decline to answer any question during the interview for any reason. Every precaution 
will be taken to secure participants' personal information to ensure confidentiality. 
Sharing of private health information (PHI): There is the potential risk for a breach of 
confidentiality. Private health information will be collected, accessed and stored according 
to HIPAA guidelines, including the use of multilevel password protection and enforcement 
of system user privileges on the database. To limit the risk of disclosure to the minimum 
necessary to conduct the study, all direct identifiers will be removed as soon as possible and 
codes will be substituted for personal identifiers. Records of individuals are stored with ID 

 
  
 
 
 
23 
numbers and a code with no discernible personal identifiers. Code lists and data files will be 
stored in separate, secure locations. Data will be stored on institutional secure servers hosted 
and accessed on password-protected computers. To maintain confidentiality, codes will be 
used in the database, presentations and publications. 
9.3.3 Potential Benefits of Trial Participation 
Participants may indirectly benefit from identification of abnormalities such as diabetes 
from the hemoglobin A1c or OGTT. If clinically relevant abnormalities are found, the 
family will be notified. With the consent from the family, clinically relevant tests results will 
be shared with the subject’s primary care physician. Participants found to have an impaired 
fasting glucose or impaired glucose tolerance who are not already under care for the 
condition will be referred appropriately for further management and treatment.  
9.3.4 Risk-Benefit Assessment 
As the risk is no more than minimal and there is significant potential direct and indirect 
benefits, the risk-benefit balance is favorable.  
9.4 Recruitment Strategy 
Potential subjects will be identified through weekly review of Pediatric Endocrinology and 
Diabetes clinic schedules. In addition, a list of potentially eligible patients will be generated 
via review of a list of patients with diagnosis of prediabetes or obesity and insulin resistance 
from current and previous research conducted by the PI or the PI’s mentor and co-
investigator, Dr. Silva Arlsanian. The Wellness and Obesity Registry, monitored by Dr. 
Silva Arslanian, will be used to screen for potential subjects as well.The CAYAH 
RESEARCH INTEREST FORM will also be used for recruitment purposes. This is 
a REDCap form with a survey link that will contain questions for adolescents to answer self-
screen questions which are non-sensitive. Center for Adolescent and Young Adult Health 
(CAYAH) clinical staff will manage and distribute this survey. CAYAH clinical research 
staff will advertise the study to the teen. If the teen (age 13 or older) indicates interest in the 
study by viewing the study advertisement within the CAYAH RESEARCH INTEREST 
FORM, they will provide their contact information to the CAYAH clinical research staff 
who will then share it with the study team.  Medical records of potential subjects will be 
screened by the study team using the protocol inclusion and exclusion criteria. Those who 
appear to meet the criteria will be approached by a member of the study team by phone, 
email, or in-person and asked if they would like to hear about the study. Subjects and/or 
their parent/guardian will provide demographic, social, and medical information about 
themselves, their child, or family (as applicable) to confirm eligibility.  
 
9.5 Informed Consent/Assent and HIPAA Authorization 
9.5.1 Screening  
Information obtained via chart review will be preparatory to enrollment and will be limited 
to the minimum necessary information to determine eligibility for the main study.  

 
  
 
 
 
24 
9.5.2 Informed consent 
Consent/assent (as applicable) will be signed electronically via REDCap. A combined 
consent/assent-authorization document will be used, and subjects will be provided with a 
copy of the consent form. Subjects will be allowed to read the consent form and ask 
questions. Written consent/assent will be obtained from the family after all the questions and 
discussions have been completed and we are reassured that subjects comprehend the nature 
of the study, the study procedures and the risks-benefits of participation. To maximize 
subject privacy, the discussion will take place in a private location in or near PCTRC or the 
Endocrinology clinic, or via phone. A copy of the fully signed and completed consent form 
will then be provided via email.  
To avoid coercion, we will explain that study participation is voluntary and the subject does 
not have to partake in the study in order to receive care at CHP. Decision not to participate 
or decision to withdraw after consent for study participation will not cause penalties or loss 
of any benefits otherwise entitled to the subject as a patient. In addition, the subject’s current 
and future medical care at CHP will not be affected by final decision for or against study 
participation.  
9.5.3 Re-Consent Plan for Subjects Who Reach Age of Majority 
Individuals who turn 18 while enrolled in the study will be contacted by phone and will be 
asked to provide consent/HIPAA authorization for their continued participation via 
REDCap.  
9.6 Payment to Subjects/Families 
All study procedures and expenses will not be billed to the participant but rather to the 
study’s funding source. 
9.6.1 Reimbursement for travel, parking and meals 
Reimbursement will be provided for travel/parking for study visit: $20, given via Vincent. 
Incentives and compensation will be provided via Vincent as described below. 
9.6.2 Payment Schema  
Study Visit: Compensation: $100; Reimbursement for travel/parking: $20; paid upon receipt 
of CGM transmitter and ActiGraph 
ActiGraph wear during Observation Period: Incentive of $20 if worn on at least 8 days out 
of 10  
Individual interview by phone/videoconference: Compensation of $15 
Total: Max compensation $135; max reimbursement for travel: $20 

 
  
 
 
 
25 
10 PUBLICATION 
After completion of the study, the investigator and study team will review and analyze the 
data for reporting and publication. All published data will be de-identified. No individually 
identifiable PHI will be published. 
 
 

 
  
 
 
 
26 
 
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