Overcoming Barriers and Obstacles to Adopting Diabetes Devices (ONBOARD) Trial
Phase: NA
Conditions: Type 1 Diabetes
Sponsor: Molly Tanenbaum

 
 
 
 
Overcoming Barriers and Obstacles to Adopting 
Diabetes Devices (ONBOARD) Trial   
 
Study Protocol and Statistical Analysis Plan 
NCT04672655 
November 11, 2020 

 
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ONBOARD: Overcoming Barriers and Obstacles to Adopting Diabetes Devices 
Version 1 
November 2020 
 
 

 
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CHAPTER 1: INTRODUCTION 
 
1.1. Purpose 
The primary objective of this randomized controlled trial is to examine the impact of a behavioral support 
intervention for adults with type 1 diabetes (T1D) who are starting on continuous glucose monitoring (CGM). 
This trial compares adults with T1D who are starting on CGM with behavioral supports (the intervention group) 
versus those who are starting on CGM without behavioral supports (the control group). We will examine group 
differences over a 3-month period on two sets of outcomes. The first set of outcomes includes glycemic 
variables (e.g. hemoglobin A1c, time in range). In this set of outcomes, A1c is the identified primary endpoint. 
The second set of outcomes includes psychosocial variables (e.g. diabetes distress, worry about 
hypoglycemia, technology attitudes), with diabetes distress as the primary endpoint. After the initial comparison 
of intervention to control across the first 3 months after starting CGM, we will conduct a longitudinal follow-up 
of glycemic and psychosocial outcomes at 6 and 12 months.  
 
1.2. Background 
1.2.1. Type 1 Diabetes (T1D) is a burdensome chronic disease; many adults with T1D do not meet treatment 
targets. The Centers for Disease Control and JDRF data estimate that there are over 1 million adults in the US 
with T1D (1, 2); 15,000 adults are newly diagnosed with T1D annually and by 2050 4.4 million adults in the US 
are expected to have T1D (1). T1D requires constant attention to glucose levels, food intake and physical 
activity, and insulin dosing decisions. Giving too much or too little insulin could result in hypo- or 
hyperglycemia, both of which carry risks of developing long-term complications. National data show that the 
majority of adults do not meet ADA’s recommended glycemic target of A1c<7.0% (86% of adults 18-25; 70% of 
adults over 25) (5). Adults with T1D are well-positioned to benefit from behavioral interventions that are tailored 
for their unique needs and integrated into clinical care.  
1.2.2. Existing and emerging diabetes technologies can dramatically improve health and reduce burden, but 
adoption rates are low. Diabetes technology offers major advances in diabetes management that reduce self-
management burden and improve health outcomes and quality of life for individuals with T1D (6-8). These 
devices include continuous glucose monitoring (CGM) systems and insulin pumps. CGM technology provides 
in-the-moment information about glucose levels, including direction and speed of change. CGM reduces 
management burden by reducing the need for frequent finger sticks. CGM has been shown to be cost-effective 
(9) and to help adults improve both glycemic control and time spent in target glucose range without increasing 
risk of hypoglycemic episodes or diabetic ketoacidosis (10-12). Furthermore, improvements in CGM accuracy 
have enabled the crucial next step toward automating diabetes management with closed loop systems. Closed 
loop systems have shown the ability to reduce hypoglycemia and glucose variability and increase time in range 
(16-20). In addition, these systems decrease the mental burden of living with T1D (21-23). To experience the 
benefits of current and future diabetes technologies adults with T1D must be willing to wear and maintain a 
CGM and insulin pump over time. We know that currently, more than half (~62%) of individuals with T1D use 
insulin pumps in the US (5), while only 14% of adults with T1D currently use CGM. Further, a concerning 
proportion of adults (27%) quit CGM within the first year due to the daily burden of using the device (24). 
Providing adults with T1D with the resources and tools to work through modifiable barriers could lead to 
continued CGM use and increased readiness for closed loop.  
1.2.3. There is no official standard of care for CGM initiation. 
Table 1 presents CGM recommendations from ADA’s 2018 
Standards of Medical Care in Diabetes (42). ADA 
recommends that adults receive robust education, training, 
and support for CGM use (42); this recommendation comes 
from expert consensus and clinical experience. There is a 
need to develop high-quality, evidence-based behavioral 
interventions to provide recommended training and support. If adults with T1D receive comprehensive 
education and support alongside CGM initiation, they may be more likely to use the devices and to experience 
short- and long-term health and quality of life benefits. Given that CGM is becoming part of “usual care” for 
Table 1. ADA 2018 Recommendations for CGM 
Current recommendation              State of the science         
(CGM)…is a useful tool to 
lower A1C in adults with T1D. 
A - Strong evidence 
Robust diabetes education, 
training, support are required 
for optimal implementation 
and ongoing use. 
E- Expert consensus 
or clinical experience 
(clinical trials needed) 
(ADA, 2018) 

 
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people with T1D and is a component of closed loop systems, the next key step is to test interventions that 
provide additional resources and support for CGM uptake versus CGM alone.  
1.2.4. The need for guided diabetes device ‘onboarding’. To address the need for increased support for 
initiating diabetes devices, the overall objective of the proposed study is to provide adults with T1D with a 
tailored behavioral intervention using evidence-based strategies and tools to enable them to maximize benefit 
from CGM and increase readiness for closed-loop technology. According to the widely used Technology 
Acceptance Model (44), factors such as the technology’s perceived usefulness and ease of use influence 
likelihood of using and benefitting from the technology. Therefore, our ONBOARD (Overcoming Barriers & 
Obstacles to Adopting Diabetes Devices) intervention package will prepare adults with T1D to use and benefit 
from CGM by 1) setting realistic expectations for the technology; 2) providing resources and problem-solving 
skills to work through barriers; 3) helping to highlight benefits of the technology; and 4) planning for potential 
issues that may arise in the future to prevent CGM discontinuation. This study addresses a major gap in the 
literature on what guidance and support adults with T1D need, beyond education, to benefit from advances in 
diabetes devices and to increase their readiness to adopt new diabetes technologies.  
 
1.3. Preliminary Studies 
The preliminary work described here focused on identifying modifiable barriers to diabetes device use, 
pinpointing targets for intervention, and highlighting links between intervention targets and important diabetes 
outcomes. 
1.3.1. We found that non-users of CGM are 
younger, have higher A1c values, and more 
negative attitudes toward diabetes technology 
compared to CGM-users. Through an online survey 
of participants in the T1D Exchange Clinic Network, 
we collected data from 1,503 adults with T1D 
regarding their current device use and major 
barriers to using diabetes devices (54.7% women; 
mean age=35.3±14.8 years; mean diabetes 
duration=20.4±12.5 years; 70% using insulin 
pumps; 37% using CGM). On average, non-users of CGM were 5 years younger; had higher A1c values (.37% 
higher mean A1c); and reported more barriers to device use compared to CGM users (22).  
1.3.2. Physical, data, social, and trust barriers interfere with CGM use. In the same survey, barriers to using 
diabetes devices (CGM and insulin pump) fell into several categories: 1) hassle/ burden of wearing devices on 
the body; 2) nervous to rely on the technology; 3) time burden of managing diabetes; and 4) devices drawing 
unwanted attention from others (Table 1). We conducted a follow-up survey of adults who had discontinued 
using diabetes devices to learn their reasons for discontinuation (Table 2). Rates of CGM discontinuation are 
considerably higher than pump discontinuation (5). After cost, issues with alarms, accuracy, discomfort and 
pain led to CGM discontinuation. Our preliminary data highlight why many adults with T1D feel the negatives 
outweigh positives of CGM and stop using this beneficial technology. 
Survey data strongly support the ADA recommendation for robust 
support tailored to the commonly endorsed barriers to using CGM to 
promote increased uptake and sustained use of CGM and, 
eventually, closed loop systems. 
1.3.3. Closed loop systems depend on CGM accuracy to gain user 
trust. Closed loop systems require wearing a CGM and an insulin 
pump and partially automate insulin delivery. Given the novelty of 
closed loop systems, we aimed to understand major factors that 
could influence willingness to trust and accept the potential risks of 
closed loop. I applied my expertise in qualitative research methods to analyze focus groups with participants in 
a closed loop system trial (n=32). Results showed that user expectations and trust shaped overall satisfaction 
with the system and likelihood of continued use. Specifically, overly high/unrealistic expectations contributed to 
increased negative evaluations of the system (3). Issues with CGM accuracy and intrusiveness of alerts hurt 

 
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user trust and decreased the likelihood that someone would opt to continue using the system (24). Relatedly, 
our extensive interviews with adults with T1D (n=113) highlighted that CGM accuracy was a major priority 
when considering closed loop system adoption (45), since accuracy of CGM determines the system’s ability to 
improve glycemic control. Our results highlight additional potential barriers and intervention targets to promote 
adoption and sustained use of CGM, and to increase readiness for using closed loop systems. Results 
demonstrate the investigator’s strong ability to conduct qualitative research related to T1D experience. 
1.3.4. Interventions with problem-solving, motivational interviewing, and social learning components can 
improve psychosocial and health outcomes in adolescents and adults with diabetes. Multicomponent 
interventions are advantageous because they capitalize on effective pieces of existing, evidence-based 
interventions (46, 47). Multicomponent interventions that include motivational interviewing, problem-solving, 
and cognitive behavioral therapy have demonstrated ability to improve A1c in T1D (48-50). Extensive evidence 
supports the benefit of problem-solving interventions for diabetes management (51-57). Motivational 
interviewing has also proven to be effective in promoting positive behavior change in diabetes management 
(58-60). Finally, successful programs to improve psychosocial and health outcomes often incorporate a social 
component, whether through group delivery (61), an online forum (63), or involvement of a peer coach (64-68). 
While these strategies can be beneficial, another powerful tool, informed by social learning theory (69), is to 
incorporate videos of first-person stories that model how individuals worked through relevant problems (70, 
71). For example, YourWay, an Internet-based, social learning and problem-solving program, helped 
adolescents with T1D work through psychosocial barriers to diabetes self-management (63). Through digital 
storytelling, YourWay presented participants with first-person “stories” of diabetes problem-solving, which can 
help individuals develop problem-solving skills and self-efficacy through “vicarious learning” (72, 73). 
 
 

 
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CHAPTER 2: STUDY PROTOCOL 
 
2.1. Synopsis of study protocol 
 
The primary objective of this randomized controlled trial is to examine the impact of a behavioral support 
intervention for adults with type 1 diabetes (T1D) who are starting on continuous glucose monitoring (CGM). 
This trial compares adults with T1D who are starting on CGM with behavioral supports (the intervention group) 
versus those who are starting on CGM without behavioral supports (the control group). We will examine group 
differences over a 3-month period on two sets of outcomes. The first set of outcomes includes glycemic 
variables (e.g. hemoglobin A1c, time in range). In this set of outcomes, A1c is the identified primary endpoint. 
The second set of outcomes includes psychosocial variables (e.g. diabetes distress, worry about 
hypoglycemia, technology attitudes), with diabetes distress as the primary endpoint. After the initial comparison 
of intervention to control across the first 3 months after starting CGM, we will conduct a longitudinal follow-up 
of glycemic and psychosocial outcomes at 6 and 12 months.  
 
2.2. Study procedures 
 
Participants will be recruited at Stanford University through a combination of in-clinic, in community locations 
and online through type 1 diabetes online communities. Eligible participants will be adults (ages 18-50) who 
have not been using CGM consistently (>5 days/week) for at least the past 6 months. Once identified in clinic 
or once someone has expressed interest in the study, study staff will 
approach potential participants to explain the study, determine 
eligibility, and obtain informed consent. All participants will complete 
their baseline visit remotely. This baseline visit will include 1) 
completing a hemoglobin A1c test kit that is mailed to them in 
advance; 2) completing a baseline assessment survey online via a 
secure site (REDCap) to obtain demographic and psychosocial data 
and 3) initiate use of CGM supplies. Participants will be given the 
choice of using Dexcom G6 or Libre 2 CGM. Participants will be 
mailed 12 weeks of CGM supplies of their choice and will receive 
initial standard CGM introduction and education from the study staff 
and will be provided with standard resources from the device 
manufacturer at this baseline visit. At baseline, participants will then 
be randomized. We will randomize at a 1:1 ratio, intervention to 
control. Those randomized to the intervention (ONBOARD) condition 
will schedule 4 60-minute sessions with study interventionist (every 
2 weeks), with the first session scheduled for 2 weeks after CGM 
initiation. Sessions will be conducted via a secure, HIPAA-compliant, 
videoconferencing software (Zoom) and may be recorded to ensure 
consistency and quality of the intervention across participants and 
interventionists. Each participant will receive one unique Zoom link 
that they will use for all 4 of their study sessions. At the 3-, 6-, and 
12-month time points, participants will be mailed A1c test kits for 
follow-up A1cs, and will complete a follow-up REDCap survey at 
these time points as well. The follow-up survey will assess 
psychosocial variables, technology satisfaction, and changes to 
demographic/medical information. Each follow-up survey is expected 
to take 30 minutes to complete. Of note, all study participants will 

 
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receive instruction on how to work with their insurance to obtain coverage for continuing to use CGM after the 
first 12 weeks of the study. At the 3-, 6-, and 12-month timepoints, CGM data downloads will be obtained.  
 
2.3. Study groups 
 
There are two groups in this study: intervention (ONBOARD) and control (CGM-only). All participants will 
receive 12 weeks of CGM supplies and will receive standardized education about getting started with CGM. A 
person trained in delivering education about CGM will deliver education about CGM use and will be present 
during a virtual meeting while participant is inserting first sensor during training. This individual will be available 
to assist with questions from participants. In addition, Dexcom and Abbott representatives are available to 
participants for technical questions or issues with the system, just like the access any CGM user has. All 
participants in both groups will be required to actively use CGM for 12 weeks. After that time period, they can 
continue or discontinue use of CGM. If they decide to continue, the study team will provide information on 
working with insurance and with their provider to obtain CGM for both study groups. 
 
After randomization, participants in the intervention group will receive 4 one-on-one sessions of ONBOARD 
(OvercomiNg Barriers & Obstacles to Adopting Diabetes Devices). Sessions will be held every 2-3 weeks over 
the 12-week period 
when participants 
are using CGM 
provided by the 
study. ONBOARD 
is a multicomponent 
intervention to 
provide tailored 
support for CGM 
adoption. Session 
content and 
strategies are 
outlined in Table 3. 
Sessions target four 
primary topics. 
Each participant will 
receive content in 
the same order, but 
the program is 
designed to be 
flexible depending 
on individual 
barriers and 
concerns. Some 
participants may 
spend more time on 
certain topics than 
others. ONBOARD 
will approach CGM 
data interpretation 
with the goal of reducing ‘data overload’ and to empower participants to use data in a way that works for them. 
Setting alerts/alarms, understanding trend arrows, reviewing the data for patterns and trends, and identifying 
common reactions that may arise with this quantity of glucose data. Participants will first increase comfort with 
data quantity, change arrows, and alarms, and then will learn to examine data for patterns and trends. Study 
personnel will not directly suggest insulin dosing and may encourage participants to talk with their care team 
when relevant. ONBOARD sessions will be delivered individually to participants by a doctoral level 
Table 3. ONBOARD Intervention Topic Content 
Barrier 
addressed 
Topic name 
Strategies used 
Goals 
 
Introduction 
- Psychoeducation; 
rapport building 
- Provide rationale for ONBOARD 
- Introduce concepts from Technology Acceptance 
Model to discuss CGM pros and cons 
Physical 
Wearing 
Diabetes 
Device(s) 
- Experiential wear 
- Troubleshooting device placement 
- Provide education and examples of problem solving 
for common concerns and strategies for navigating 
them: appearance, insertion, skin irritation, 
discomfort, interference with daily activities 
- Provide resources for adhesive, skin prep, and 
adhesive removal 
Data 
Managing 
CGM Data 
- Education 
- Behavioral: 
optimizing alert 
thresholds 
- Cognitive: 
Identifying 
thoughts & 
feelings 
- Provide information on trend arrows 
- Review options for customizing alert thresholds  
- Identify common thoughts and feelings that may 
arise from receiving data (e.g. managing reactions to 
double arrows) and identify helpful thoughts 
Demonstrate how to view data on Clarity or 
LibreView 
Social 
CGM and 
Social 
Situations 
- Problem solving 
- Demonstrate problem solving common issues that 
arise with using and wearing diabetes devices 
around others (e.g. answering questions about 
devices, engaging with diabetes around others 
- Practice using problem-solving exercise in session 
Trust 
Building 
Trust 
- Psychoeducation 
- Social problem 
solving  
- Demonstrate how others have developed trust and 
what they do when trust in a device is broken (e.g. 
listening to body, using meter) 
 
Wrapping 
Up 
- Goal-setting 
- Motivational 
Interviewing 
- Reviewing perceived benefits of the technology as 
they relate to, or are weighed against, perceived 
issues.  
- Anticipate future barriers that may lead to CGM 
discontinuation to brainstorm possible alternative 
actions. 

 
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psychologist with diabetes expertise. Each session will include relevant first-person digital stories from adults 
with T1D, recounting how they managed relevant CGM barriers. Sessions will be delivered via a HIPAA-
compliant videoconference program. 
 
2.4. Coordination of study procedures with clinical care  
 
This study will not be directly connected to participants’ clinical care. Participants will be encouraged to contact 
their care providers during the study to pursue initiating CGM use after study supplies run out and participants 
in the ONBOARD intervention will be provided education on how to advocate for getting the devices they need 
with their providers and with their insurance companies.  
The study staff will have primary role of initiating CGM at the start of the study for all participants and providing 
training on insertion. Participants will also receive information from study staff on how to share their CGM data 
with their diabetes providers.  
 
2.5. Study visits and assessments 
 
All participants will attend a baseline study visit. Baseline is the date they complete their first assessment and 
begin using their CGM and will receive training from study staff on beginning to use CGM. After baseline, only 
participants randomized to ONBOARD will receive 4 additional study visits. Remaining assessments (A1c, 
CGM data downloads, and surveys) will be done via mail and electronically, respectively.  
 
Study assessments for both groups will occur at baseline, 3 months, 6 months and 12 months post-baseline. 
We will conduct these assessments and obtain glucose data to examine changes over time in glycemic and 
psychosocial variables. Participants will receive a $25 gift card for each assessment they complete. 
 
Assessment components are included in Table 4.  
 
Table 4. Study Measures 
Domain 
Measure 
Description 
0 
mos 
 3 
mos 
6 
mos 
12 
mos 
Demographic 
History questionnaire 
Medical, personal, device history 
X 
 
 
 
Demographic/medical update 
Changes to baseline information 
 
X 
X 
X 
Psychosocial 
Diabetes Distress Scale-T1D 
28-item validated measure of T1D distress in adults 
X 
X 
X 
X 
Fear of Hypoglycemia - Worry 
18-items; measure of fears related to severe low BG 
X 
X 
X 
X 
Hypoglycemic Confidence Scale 
9 items; validated for adults with T1D 
X 
X 
X 
X 
Diabetes Self-Compassion Scale 
19 items; validated for adults with T1D 
X 
X 
X 
X 
Patient Health Questionnaire-8 
8 items; assesses depressive symptoms 
X 
X 
X 
X 
GAD-7 
7 items; assesses anxiety symptoms 
X 
X 
X 
X 
Perceived Stress Scale 
10 items; assesses stress and coping in past month 
X 
X 
X 
X 
World Health Organization-5 
5 items; assesses emotional wellbeing 
X 
X 
X 
X 
Self Care Inventory-Revised 
15 items; measure of a range of self-care activities 
X 
X 
X 
X 
Social Support Questionnaire 
6 items; assesses availability of social support 
X 
X 
X 
X 
Diabetes Empowerment Scale-SF 
8 items; assesses diabetes self-efficacy 
X 
X 
X 
X 
COVID-related impacts 
Assesses general and diabetes-specific impacts of 
pandemic 
X 
X 
X 
X 
Technology-
specific 
INSPIRE survey 
Assesses closed loop attitudes 
X 
 
 
X 
Glucose Monitoring System 
Satisfaction Survey (GMSS-T1D) 
15 items; validated measure of glucose monitoring 
device-related treatment satisfaction and quality of life 
X 
X 
X 
X 
Barriers to device use 
19-item list of barriers 
X 
X 
X 
X 
A1c 
Glycemic control 
X 
X 
X 
X 

 
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2.6. Study population 
 
The participant population is adults with type 1 diabetes ages 18-50. In order to have 76 participants per arm 
(152 total) we will enroll up to 178 adults with T1D and then randomize them to either the intervention 
(ONBOARD, n=89) or control group (CGM-only, n=89).  
 
2.6.1. Eligibility criteria 
 
To be eligible for the study, an adult must meet the following criteria: 
 
1. Clinical diagnosis of type 1 diabetes 
2. Age between 18 and 50 years at time of screening 
3. Comprehension of written and spoken English 
4. Lack of consistent continuous glucose monitoring use (>5 days/week) for past 6 months 
5. No severe medical conditions, which in the opinion of the investigators are likely to hinder participation 
in this clinical trial 
 
2.6.2. Exclusion criteria 
 
The presence of any of the following is an exclusion for the study: 
1. Subject has a medical disorder that in the judgment of the investigator will interfere with completion of 
any aspect of the protocol (e.g. pregnancy, kidney disease, skin condition that may hinder sensor 
application). 
2. Subject has a neurologic disorder that in the judgment of the investigator will affect completion of the 
protocol. 
 
2.7. Data analysis plan 
Our team has extensive experience in the use of web-based assessment, data management and data 
anlysis. Quantitative data will be entered into an online encrypted, HIPAA-compliant data management system, 
REDCap, with secure access for unique study IDs assigned to each participant. REDCap survey data is then 
ready for download by study staff and will be imported into SPSS for data cleaning and analysis. CGM data will 
be downloaded via Dexcom Clarity and LibreView which create a CSV file for transfer to REDCap and data 
analysis programs.  
Demographic, medical, psychosocial variables, and some outcome measures are surveys and multi-
item scales that participants will answer in REDCap. Psychometric properties of scales will be assessed before 
proceeding to investigate the proposed aims. These psychometric properties include item-total correlations and 
Cronbach’s α to assess reliability. Total scores and subscale scores, when available, will be calculated and 
used for statistical analyses. Descriptive statistics will calculate frequencies, means and standard deviations for 
study variables. Independent samples t-tests and c2 analyses will assess potential differences between groups 
at baseline in demographic, psychosocial and diabetes variables. Analyses for Hypotheses 1&2 will follow the 
intention-to-treat principle.  
To test Hypotheses 1&2, we will first conduct a treatment group comparison (ONBOARD vs. CGM-only) 
of the change in A1c, the primary outcome, from baseline to 3, 6, and 12 months. Specifically, we will use 
linear mixed models to model changes in A1c as a function of time, intervention assignment, and group-by-
time interaction. These models will include a subject-specific random effect to account for the correlation of 
A1c and CGM 
data 
% time in range; percent time in 
hypoglycemia and hyperglycemia; 
additional indices of variability 
including standard deviation 
Glycemic control from CGM 
X 
X 
X 
X 
% time wearing CGM 
Data from CGM 
X 
X 
X 
X 
Satisfaction 
Satisfaction survey (for ONBOARD 
participants only) 
 
 
X 
 
 

 
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outcomes over time within a subject. We will examine change from baseline for each outcome as the 
dependent variable. We will begin by fitting models with minimum covariates prior to considering additional 
covariates. Similar models will be used to examine secondary outcomes of time in range, days of CGM wear 
(Hypothesis 1), diabetes distress, and perceived CGM benefit (Hypothesis 2). We will reference information 
criteria (e.g., Akaike’s) to inform model selection decisions. Beyond testing the groups-by-time interaction term, 
custom contrasts will assess group differences at each time point. Exploratory analyses will examine 
differences between subgroups over time after primary, intent-to-treat analyses are completed. Additional 
exploratory analyses will examine patient-level predictors of CGM wear (e.g. age, gender, diabetes duration). 
For the CGM-continuer subgroup, we will conduct exploratory longitudinal analyses using CGM data to look at 
changes in time in range. We will adjust for multiple comparisons by using the Benjamini-Hochberg procedure 
and a false discovery rate of 0.05 (78). Analyses will initially be conducted without imputation for missing 
values, using the missing-at-random approach (79) and then multiple imputation will be used to supply values 
for missing data. We will conduct sensitivity analysis by multiple imputation to compare the effects. 
Enrolling and randomizing a sample of 178 adults with T1D (1:1 randomization; 89 per arm) will be 
sufficient to investigate the hypotheses in this study. Based on our previous related work, we estimate 15% 
attrition, yielding a final sample size of 76 participants per arm (152 total). This target sample size is based on 
the following pieces of data. First, effect sizes comparing CGM to non-use in adults with T1D are in the 
moderate (d=.40-.50) range (8, 75, 76), showing improvements in A1c and time in range during CGM use. 
Further, standardized effects of diabetes behavioral interventions for adults are in the small to moderate range 
with .35 to .40 SD unit differences (43, 77). In the proposed study, we hypothesize group differences in A1c of 
a similar or greater magnitude will be driven by a combination of greater sustained use of CGM over the 12-
month follow-up period in the ONBOARD program and added utility and benefits from use resulting from the 
ONBOARD program. Sample size estimates for comparison of ONBOARD and CGM-only are based on intent-
to-treat analyses, alpha=.05, 80% power, autocorrelation of .50 (7), a repeated measures ANOVA on change 
between the 2 groups from baseline to 3, 6 and 12 months. A sample of 89 participants assigned to 
ONBOARD and 89 to CGM-only will provide power to exceed 0.80 for the primary outcome of A1c for 
moderate effects of d=.35 or greater. The sample size allows detectable mean differences in the magnitude of 
A1c≥0.5% (conservatively assuming 1.2 SD; recent registry data suggests our SD will be closer to 1.0). A 0.5% 
A1c is the minimum clinically significant difference regarded by physicians and stakeholders. Treatment 
guidelines and algorithms from ADA/EASD and UK National Institute for Clinical Excellence have 
recommended evaluating new treatment regimens by whether A1c is lowered by 0.5% or more. Between clinic 
and wider T1D community, we will have ample ability to reach our recruitment goal. 
 
2.8. Expected duration of study participation 
Duration of study participation is expected to be 1 year. 
 
 

 
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CHAPTER 3: ADVERSE EVENT REPORTING AND SAFETY MONITORING 
 
3.1. Overview of Safety Monitoring 
 
Safety monitoring will be performed by Drs. Tanenbaum (PI) and Hood (Mentor) on an ongoing basis. Safety 
data will be gathered and reviewed periodically by the study investigators. Reviews will occur every two 
months during the course of the trial and the study staff will examine occurrence of adverse events and 
whether participants are satisfied with their participation. The PI will be responsible for evaluating each 
unanticipated problem and determining whether it affects the risk/benefit ratio of the study and whether 
modifications to the protocol and consent forms are required. The PI will be responsible for reporting 
unexpected problematic events involving any aspect of the study to the NIH and local IRB per institutional 
guidelines. Unanticipated problems to be assessed include adverse events, deviations from the study protocol, 
problems with informed consent, and confidentiality violations. The PI will report unanticipated problems to the 
NIH and IRB within 3 business days of their occurrence. The local IRB will review such cases and determine 
what actions must be taken to address or resolve the situation. As this study employs an FDA-approved device 
and the team is providing additional support, it was determined that there is no need for a Data Safety and 
Monitoring Board (DSMB). 
 
3.2. Definition of an Adverse Event 
 
Reportable adverse events in this study include any untoward medical occurrence that meets criteria for a 
serious adverse event or any medical occurrence (expected or unexpected) in a study participant that is study-
related.  
 
Hypoglycemic events are recorded as adverse events if the event required assistance of another person due to 
altered consciousness and required another person to actively administer carbohydrate, glucagon, or other 
resuscitative actions. This means that the subject was impaired cognitively to the point that he/she was unable 
to treat his or herself, was unable to verbalize his or her needs, was incoherent, disoriented, and/or combative, 
or experienced seizure or coma. These episodes may be associated with sufficient neuroglycopenia to induce 
seizure or coma. If plasma glucose measurements are not available during such an event, neurological 
recovery attributable to the restoration of plasma glucose to normal is considered sufficient evidence that the 
event was induced by a low plasma glucose concentration.   
 
Hyperglycemic events are recorded as adverse events if the event involved diabetic ketoacidosis (DKA), as 
defined by the DCCT, and had all of the following:  
 
× 
Symptoms such as polyuria, polydipsia, nausea, or vomiting;  
× 
Serum ketones > 1.0 mmol/L or large/moderate urine ketones;  
× 
Either arterial blood pH <7.30 or venous pH <7.24 or serum bicarbonate <15; and  
× 
Treatment provided in a health care facility  
Skin irritation from sensor wear will be recorded in specific sections of the case report forms. An adverse event 
form is only completed if skin irritation is severe.  
 
Distress or discomfort experienced by participants as they complete surveys is not considered an adverse 
event. However, we have trained psychologists on staff who will be available to address any distress or 
discomfort and initiate referrals if requested. 
 
3.2. Recording of adverse events 
 
Throughout the course of this study, all efforts will be made to remain alert to possible adverse events or 
untoward findings. The first concern will be the safety of the participant, and appropriate medical intervention 
will be made. 

 
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The investigator will elicit reports of adverse events from the participant at each visit and phone call and 
complete all adverse event forms online. The study investigator will assess whether an adverse event is 
related or unrelated to the study by determining if there is a reasonable possibility that the adverse event may 
have been caused by the study procedures.  
 
The intensity of adverse events will be rated on a three-point scale: (1) mild, (2) moderate, or (3) severe.  It is 
emphasized that the term severe is a measure of intensity: thus a severe adverse event is not necessarily 
serious. For example, itching for several days may be rated as severe, but may not be clinically serious.   
 
Adverse events that continue after the participant’s discontinuation or completion of the study will be followed 
until their medical outcome is determined or until no further change in the condition is expected.  
 
3.3. Reporting serious or unexpected device-related adverse events 
 
A serious adverse event is any untoward occurrence that: 
- 
Results in death 
- 
Is life-threatening; (a non life-threatening event which, had it been more severe, might have 
become life-threatening, is not necessarily considered a serious adverse event) 
- 
Requires inpatient hospitalization or prolongation of existing hospitalization 
- 
Results in significant disability/incapacity  
- 
Is a congenital anomaly/birth defect 
 
3.4. Unanticipated adverse device event  
 
An unanticipated adverse device event is defined as an adverse event caused by, or associated with, a device, 
if that effect or problem was not previously identified in nature, severity, or degree of incidence. 
 
Serious or unexpected adverse events must be reported to the coordinating center immediately via completion 
of the online serious adverse event form. 
 
The principal investigator will notify all participating investigators of any adverse device event that is both 
serious and unexpected. Notification will be made within 10 days after the PI becomes aware of the event.  
 
The PI is responsible for informing their IRB of serious study-related adverse events and abiding by any other 
reporting requirements specific to their IRB. 
 
3.5. Potential risks and side effects 
 
Loss of confidentiality is a potential risk and is protected by the safeguards discussed above. Hypoglycemia, 
hyperglycemia, and ketone formation are always a risk in subjects with type 1 diabetes. Subjects will be closely 
monitored for this. When wearing CGM sensors there are risks of skin rashes, allergic reactions to tape, 
infections at the insertion site, or small pieces of the sensor breaking off or remaining under the skin. These 
risks will be monitored, but study staff will not oversee insertions, tracking of sensor information, and other 
diabetes device information. 
 
3.5.1. Hypoglycemia 
 
There is always a risk of hypoglycemia for patients with insulin-dependent diabetes. The frequency of 
hypoglycemia during this study is not expected to be greater than the risk incurred during daily living. If severe 
hypoglycemia occurs, it is readily treated with either oral glucose or glucagon injection. To minimize the risk of 
hypoglycemia due to “stacking” insulin doses, study participants will be instructed in their initial education not to 
take rapid acting insulin injections to correct hyperglycemia more than once every 3 hours. The low alert level 

 
12 
 
will be set at 75 mg/dL for all study participants at the outset of the study; however, participants can change 
these alerts if they would like. 
 
3.5.2. Hyperglycemia 
 
Hyperglycemia and ketonemia can occur if insulin delivery is attenuated or suspended for an extended period. 
This is a risk of type 1 diabetes that is not expected to be greater during the study period than it is during daily 
living. If severe hyperglycemia occurs, participants will be advised to treat with insulin therapy or to seek 
medical attention from their diabetes care team.  
 
3.5.3. Lancing risks 
 
Finger lancing is part of the usual care for people with diabetes and should not be a significant contributor to 
risks in this study. A small drop of blood will be obtained by finger stick to measure blood glucose and HbA1c. 
This is a standard method to obtain blood for routine hospital laboratory tests. Pain is common at the time of 
lancing. In about 1 in 10 cases, a small amount of bleeding under the skin will produce a bruise. A small scar 
may persist for several weeks. The risk of local infection is less than 1 in 1000.  
 
3.5.4. Sensor site risks 
 
There is a possibility of CGM sensor site risk. Whenever the skin is broken there is the possibility of an 
infection. CGM sensors are inserted under the skin. There may be bleeding where the sensor is inserted, 
which can cause bruising. CGM site infections occur very infrequently, but, if an infection was to occur, oral 
and/or topical antibiotics can be used. The risk of skin problems could be greater if a sensor is left in longer 
than recommended. On rare occasions, the sensor wire may break or detach from the sensor pod. There is a 
remote chance that sensor fragments could remain under the skin if the sensor breaks during normal wear. 
Subjects may also develop skin irritation or allergic reactions to the adhesives used to secure the CGM. If 
these reactions occur, different adhesives (such as with IV 3000, Tegaderm, etc.) will be tried, sites will be 
rotated frequently, and a mild topical steroid cream or other medication may be required. All participants will be 
carefully instructed about proper use of sensors.  
 
3.5.5. Other potential risks 
 
A potential source of risk in this study is the risk of gathering sensitive social, behavioral, and medical 
information. Data collection via the internet will be conducted through secure applications (REDCap). There 
are no known psychological risks to subjects completing self-report attitude and behavior rating scales. or 
participating in intervention sessions. However, the survey and intervention topics may contain items or 
questions that make the subjects feel uncomfortable in that they ask about their physical and psychological 
health and feelings/emotions. Subjects will be informed that any items on questionnaires or topics discussed in 
the intervention modules that produce these effects may be skipped or ignored. Subjects will also have the 
option of not participating in conversations or exercises in the interventions that cause them discomfort. They 
will also be free to withdraw at any time. All intervention modules will be carried out by a highly trained, 
doctorate level psychologist. There are no known risks to audio recording intervention sessions. All audio 
recorded information will remain confidential and will only be accessed by study team members. Use of BG 
meter downloads offers no increased risk over standard care. Data downloaded from CGM and the home 
glucose meter will be collected for the study as measures of diabetes self-management behaviors. Some 
people may be uncomfortable with the researchers' having such detailed information about their daily diabetes 
habits. The respondent burden for completion of all data collection at each assessment point is approximately 
30-45 minutes total. All participants will be clearly informed of the time required for participation, the study 
duration, and the nature of the data to be collected. It is not anticipated that any of the data collection 
instruments will cause any adverse effects. 
 
3.6. Adequacy of protection against risks 
 

 
13 
 
3.6.1 Informed Consent and Assent.  
 
Interested participants may contact members of the study team directly or may be asked during a clinic visit if 
they wish to learn more about the study and be approached by a member of the study team. Either by phone 
or in person, a member of the study team will conduct screening for eligibility and enter this information into the 
secure server (REDCap). Eligible adults who are interested in participating will be provided with an informed 
consent form and HIPAA waiver, either electronically or hard copy. The study team member will then explain 
the purposes, benefits and risks of the project and offer them an opportunity to ask questions and/or decline 
participation. If still interested in participating, a full description of the nature of the study, the requirements of 
their participation in it, and the risks and benefits of the study will be explained to potential participants by the 
principal investigator or a trained research assistant. If an individual declines participation, the reasons for this 
will be documented and permission to record relevant demographic data from clinic records will be requested. 
This procedure allows for comparisons to be made between those who do and do not participate. If they 
consent to participate, they may do so either in written form or electronically.  
 
All minorities will be encouraged to participate. Economically and educationally disadvantaged people, and 
participants who are employed at the clinical center (Stanford) will be eligible to enroll in this study if they meet 
all the study criteria. Subjects will be recruited from our clinics, through T1D community organizations, and 
through IRB approved patient recruitment lists. We will also use IRB approved recruitment materials to post the 
study on clinicaltrials.gov and to Stanford’s research and department websites. Participants may self-select to 
join the research by responding to advertisements on social media. These posts will provide contact 
information for the research staff at each site. We will not interact with potential participants or enrolled 
participants through these media. We will actively work to prevent harm to all subjects enrolled in the study. 
We will work to avoid coercion by allowing equal enrollment opportunities for employees, as well as non-
university affiliated subjects. We will ensure that all participants are informed that their participation is 
voluntary, that they will receive no ill treatment should they decide to not participate, and that they will receive 
no special advantages, aside from those mentioned in the "benefits" section of the consent, for participating in 
the study.  
 
Participation will be voluntary. All participants must provide consent prior to inclusion in this research study. 
The primary investigator or a trained research coordinator will explain the nature, purpose, expected duration, 
and risks of study participation to each eligible participant. The primary investigator or trained research 
coordinator will also obtain consent and authorization for the release of personal information.  
 
3.6.2. Protections Against Risk  
 
All protocols and consent documents will be approved by Stanford’s IRB. All members of the research team 
have and will maintain current training in the ethical conduct of research. Dr. Tanenbaum has completed 
rigorous training in the protection of human subjects, including CITI training, and graduate coursework at 
Yeshiva University. Research assistants and mentors/advisors working on the project will also complete 
standardized training in the protection of human subjects. The plan for protecting privacy and confidentiality 
recognizes that the protection of privacy in studies involving sensitive data is of utmost importance. We will 
attempt to do this in several ways. The PI or a trained RA will introduce the study to eligible participants and 
explain the purposes, benefits, and risks of the project to the subjects, and offer them an opportunity to ask 
questions and/or decline participation. The voluntary and confidential nature of the research, as well as limits to 
confidentiality, will be highlighted during informed consent process. Study participation will not interfere with 
clinical care and all patients have standard access to their treatment team on a routine (clinical care) and 
emergency basis. All responses to interview items will be given by subjects in private. Internet data collection 
will only occur through tools and resources that have acceptable security features. We will minimize all 
communications that involve names or other identifying information. All clinically relevant and study information 
will be kept in locked files in locked offices or password protected files. 
 
Audio recordings of intervention sessions will be for quality control purposes only to ensure that sessions are 
delivered in a consistent way across participants. These audio recordings will be saved on a password-

 
14 
 
protected secure server, will be reviewed by the PI, and will be deleted upon review. Information about 
subjects will not be accessible to any nonauthorized study personnel without the written consent of the subject. 
In all datasets we will use ID numbers only. A separate dataset linking names with ID numbers will be 
accessible only to authorized study personnel under the direction of the PI.  
 
There will be an endocrinologist on call 24/7 for any severe events that should occur. Likewise, a licensed 
clinical psychologist is available for any concerns on the psychological side. Severe events are not anticipated 
but will be monitored. Study personnel are always available for questions. Hyperglycemia and ketone formation 
are always a risk in subjects with type 1 diabetes and subjects will be closely monitored for this. Subjects will 
have blood ketone meters provided through routine clinical care. Insulin can be given as a subcutaneous 
injection to treat hyperglycemia. Participants will be encouraged to contact their diabetes clinical care team and 
will also have access to phone numbers for a study physician. Participants in both groups will receive 
instruction about inserting and calibrating the sensor and will receive standardized introductory education 
about CGM. Participants are free to check blood glucose via fingerstick at any time and encouraged to do so 
if/when they notice a potential discrepancy between CGM and fingerstick values. A person trained in delivering 
education about CGM will deliver the education about CGM use and will assist with inserting the first sensor. 
This individual will be available to assist with questions from participants. In addition, Dexcom representatives 
are available to the participants for technical questions or issues with the system, just like the access any 
Dexcom user has.  
 
3.7. Study stopping criteria 
 
Individual subjects will be removed from the study for the following reasons:  pregnancy, study-related adverse 
events (i.e. severe hypoglycemia, loss of consciousness, hypoglycemia related seizure, DKA related to study-
related event requiring hospitalization), severe skin infection requiring systemic antibiotics, severe reaction to 
sensor tape, or other reasons that develop during the study that in the judgment of the investigator make it 
unadvisable for the subject to continue with the study 
 
 

 
15 
 
CHAPTER 4: MISCELLANEOUS CONSIDERATIONS 
 
4.1. Potential Benefits  
 
There are known benefits to people with T1D from using continuous glucose monitoring (CGM), including 
increased time in target range, decreased time in hypoglycemia, decreased A1c, and improvements in 
diabetes distress (7, 8, 75, 76). The potential benefit of this study is the provision of new knowledge about 
methods of optimizing the way that adults with T1D are introduced to CGM technology, with the long-term goal 
of informing methods for increasing device uptake and technology acceptance in the future in this population. 
Participants may find intervention sessions interesting and relevant. Collection of the psychosocial and clinical 
data may provide information for diabetes clinicians and other stakeholders to help optimize the way that new 
beneficial technology is introduced to their patients. The low risk of this minimally-invasive study appears to be 
far outweighed by the more compelling potential benefits.  
 
4.2. Importance of the Knowledge to be Gained  
 
Considering the relatively low uptake of CGM technology among adults with T1D and known benefits to using 
this technology, combined with ADA recommendations for robust training and support for CGM use, there is an 
urgent need to develop tailored, innovative interventions that patients can receive at the appropriate time to 
support uptake and prevent discontinuation of CGM. The knowledge gained from this study will lead to the 
development of a comprehensive behavioral recommendation to optimize CGM use in adults with T1D. This 
study will inform future, larger-scale studies that evaluate CGM training programs and promote ways of 
increasing benefit from the device and key problem-solving skills to work through hassles and barriers to 
device use. 
 
4.3. Subject compensation 
 
There will be no cost to the participants for taking part in this research study. Participants will receive $25 for 
the completion of each of the four assessments for up to $100 total. All participants will receive 12 weeks of 
CGM supplies free of charge.  
 
4.4. Subject withdrawal 
 
Participation in the study is voluntary and a subject may withdraw at any time. The investigator may withdraw a 
subject who is not complying with the protocol. For subjects who withdraw, their data will be used up until the 
time of withdrawal. 
 
4.5. Confidentiality 
 
For security and confidentiality purposes, subjects will be assigned an identifier that will be used instead of 
their name. 
 
4.6. Level of risk 
 
This research proposal is considered to have no more than minimal risk (e.g. blood draws, data collection, 
surveys, behavioral interventions, using FDA approved devices as recommended). 
 
 
 
 

 
16 
 
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