Implementation and Evaluation of a Diabetes Prevention Clinical Pathway in Primary Care
Phase: NA
Conditions: PreDiabetes, Prediabetic State
Sponsor: Johns Hopkins University

Implementation and Evaluation of a Diabetes Prevention  
Clinical Pathway in Primary Care 
NCT05265312 
Date: 7/11/2023 
 
 

Introduction 
Abstract and Background: 
Prediabetes is a significant public health problem affecting 88 million U.S. adults. Evidence 
suggests that the vast majority of people with prediabetes are unaware that they have this 
condition and many are not receiving appropriate care for prediabetes, including referral to 
evidence-based programs like the Diabetes Prevention Programs. In our retrospective cohort 
study of patients with prediabetes from Johns Hopkins Health Systems, we found that the rates 
of prediabetes clinical care activities are low. In our qualitative studies, we found that primary 
care physician (PCP) barriers include low knowledge about Diabetes Prevention Programs and 
misperceptions of insurance coverage of these programs and inadequate clinical staff to 
address prediabetes. Common patient barriers to taking action to prevent diabetes include lack 
of motivation, time and resources.   
Primary Hypothesis:  We hypothesize that the clinical pathway will result in increased clinician 
screening and intervention and improve patient engagement in diabetes prevention. We will 
compare results from the intervention clinic compared to a control clinic. If successful, we plan 
to implement and test the effectiveness of this clinical pathway across the entire health system.  
Purpose of the Study Protocol: As described above, we have conducted several studies to 
under current practices in prediabetes care across the Johns Hopkins Health Systems. In our 
retrospective cohort study of patients with prediabetes from Johns Hopkins, we found that the 
rates of prediabetes clinical care activities are low. Within 12 months, 63.4% had repeat 
glycemic testing, yet only 10.4% had coded diagnoses of prediabetes, 1.0% were referred for 
nutrition services, and 5.4% were prescribed metformin. We were unable to evaluate uptake of 
Diabetes Prevention Programs (DPPs) since a referral order was not in place until recently. In 
our qualitative studies, we found that clinician barriers include low knowledge about DPPs and 
misperceptions of insurance coverage of these programs and inadequate clinical staff to 
address prediabetes. Common patient barriers to taking action to prevent diabetes include lack 
of motivation, time and resources.   
Based on our prior research, comprehensive strategies are urgently needed to improve 
prediabetes care. Using these findings, we have designed and plan to implement a diabetes 
prevention clinical pathway which seeks to address some of these common clinician and patient 
barriers.  
Study Objectives 
Objective: Our primary objective to design and pilot test the diabetes prevention clinical 
pathway at a primary care clinic compared to a control primary care clinic.  
Study Design  
Overview: This is a non-randomized, quasi-experimental intervention study with one comparison 
group.  Eligible patients include those on the prediabetes registry who are seen in the control and 
intervention clinics during the study period. Data is collected on eligible patients during the 
baseline (pre-implementation) period and prospectively during the 12-month implementation 
period. 
 
 
 

Intervention Study Population Inclusion/Exclusion: 
• 
Adults age 18 and older, on prediabetes registry, last A1c<6.5% 
• 
Complete one visit (video or office visit) with PCP during intervention period  
Blinding 
While this study meets the NIH definition of a clinical trial, participants are not randomized or 
assigned at the patient level. The intervention is implemented clinic-wide and is intended to 
augment routine care (quality improvement). Therefore, the traditional terms of blinding in a 
clinical trial are not applicable.  
Risks and Benefits 
We believe the intervention involves minimal medical risk and is aligned with routine, evidence-
based care. Participants may benefit from the intervention because of improved follow-up care 
(including visits, labs, and referrals) which may in turn result in a decreased risk of progression 
to diabetes. We aim to fill an important gap in knowledge about successful primary care clinic 
interventions to improve diabetes prevention. We hope to address the public health burden of 
diabetes by focusing on and improving the primary prevention of diabetes. We believe that the 
risks to subjects are low and reasonable given the anticipated benefits. 
Withdrawal of Subjects 
The intervention is intended to improve and augment routine care. Since it is implemented 
clinic-wide, patients will not have the option to opt out of the intervention. Furthermore, there is 
no outcome of treatment failure since we are not assigning patients to a particular treatment. 
They will receive treatments based on individual discussions with their doctor.  
Study Procedures 
This is a pre-/post-evaluation of a diabetes prevention clinical pathway that will be implemented 
over a 12-month period at the intervention clinic. Eligible patients include those on the 
prediabetes registry who are seen in the control and intervention clinics during the study period. 
Their first visit with the PCP will be considered V0 (initial data collection) and data will be 
collected retrospectively (12 months prior to V0) and prospectively at that visit and subsequent 
primary care visits (V1, V2, V3, etc.) during the 12-month intervention period (see Figure). 
 
 
 

The diabetes prevention clinical pathway will focus on the following steps: 1) Screen/test- 
testing of eligible patients for prediabetes/diabetes, 2) Education- PCPs will be encouraged to 
take an online learning module and in-person group training on prediabetes management, and 
patients with prediabetes will receive a handout about prediabetes prior to their upcoming PCP 
visit, 3) Action- PCPs will use a shared decision-making guide and treatment algorithm to 
discuss options with patients at their visit, 4) Referral- patients may be referred to DPPs and/or 
medical nutrition therapy (MNT), and 5) Treat- patients will be scheduled for a follow-up visit 
within 3-9 months with their PCP or care team (NP) to continue addressing prediabetes.  
Group 1 Intervention clinic patients 
PCPs in the intervention clinic will be invited and encouraged to attend the 1-hour clinician 
training session at the beginning of the intervention. This is considered continuing medical 
education, and we may be able to provide continuing medical education credit for their 
attendance. The training session will include information on prediabetes treatment guidelines, 
use of EPIC clinical decision support tools and use of the patient handout to discuss treatment 
options. There will be interactive skills practice incorporated. This training session may occur on 
up to 2 occasions to capture all PCPs. We may also record the training session so that PCPs 
who could not attend can view it later asynchronously.  
Patients with prediabetes (e.g., “active” on prediabetes registry) presenting for a routine visit in 
the intervention clinic will be identified using an EPIC workbench report run the week prior to 
their upcoming visit. These patients, presenting for in-person or video visits, will receive the 
handout as an attachment either via MyChart or via email sent from REDCap.  
During the visit, the patients will be encouraged to bring the prediabetes handout to review with 
their PCP who can use the shared-decision making guide and treatment algorithm to discuss 
options with the patient. Several Epic clinical-decision support tools have been built to facilitate 
this discussion, including a prediabetes orders smartset (which includes the DPP referral) and 
prediabetes smart texts that PCPs can use to send patients information.  
Patients who complete their visit will be invited via email (or MyChart if no email on file) to 
complete an online REDCap survey. They will first receive an email to complete the e-consent 
form which explains the study and the potential risk/benefits of joining the study. When the e-
consent is completed, the patient will automatically receive a link to the survey. The survey is 
voluntary and will include up to 10 questions regarding their engagement in diabetes prevention 
behaviors and treatment, and satisfaction and acceptability of the intervention. The timing of the 
survey emails and reminders will be as follow: e-consent sent within 7 days of their visit and 
survey reminder 3 days after first invite. We will call patients who do not complete the e-consent 
form within 7 days of receipt and call patients who do not complete the survey within 5 days of 
receipt of the survey reminder. During the calls, we may offer to fill out the survey questions with 
the patient since our survey response rate has been low and this may increase uptake. Patients 
will be offered a $10 gift card if they complete the survey. Regardless of whether patients fill out 
the survey, we will collect their medical record data using the PMAP database.  
At the end of the visit, the patient will be encouraged to schedule a 3-6 month visit with their 
PCP or care team member to continue addressing prediabetes. At this follow-up visit, the same 
diabetes prevention clinical pathway steps will apply (i.e., handout sent before visit, survey to be 
completed after visit). The PCP or care team member will use the same shared-decision making 
guide and treatment algorithm to continue discussing treatment options with the patient. 

Group 2 Control clinic patients 
Patients with prediabetes (e.g., “active” on prediabetes registry) who present for a routine visit in 
the control clinic will be identified using an Epic workbench report. Their PCP will address 
prediabetes as they usually do (i.e. usual care). They can refer patients to the same 
interventions (DPP, MNT) or start metformin. PCPs will have access to the same Epic clinical-
decision support tools as the intervention clinic does but not the shared-decision making guide 
and treatment algorithm to facilitate discussion. Patients will not receive the prediabetes 
handout.  
Patients who complete their visit will be invited via email to complete an online REDCAP survey. 
They will first receive an email to complete the e-consent form which explains the study and the 
potential risk/benefits of joining the study. When the e-consent is completed, the patient will 
automatically receive a link to the survey. The survey is voluntary and will include up to 10 
questions regarding their engagement in diabetes prevention behaviors and treatment, and 
satisfaction with prediabetes care. The timing of the survey emails and reminders will be as 
follow: e-consent sent within 7 days of their visit and survey reminder 3 days after first invite. We 
will call patients who do not complete the e-consent form within 7 days of receipt and call 
patients who do not complete the survey within 5 days of receipt of the survey reminder. During 
the calls, we may offer to fill out the survey questions with the patient since our survey response 
rate has been low and this may increase uptake. Patients will be offered a $10 gift card if they 
complete the survey. Regardless of whether patients fill out the survey, we will collect their 
medical record data using the PMAP database.  
Group 3 Intervention clinic PCPs 
PCPs in the intervention clinic will be recruited to provide feedback using an online REDCap 
survey through an in-depth survey sent via email at 0m, 6m and 12m to gather feedback on 
intervention components and acceptability/satisfaction with the intervention. PCPs will receive 
an email from REDCap with the e-consent form. Once that is completed, the PCP will receive 
the survey link. All survey participants will receive a $25 gift card for completion of the in-depth 
survey. 
Safety and Adverse Events 
Enrolled participants will be monitored throughout the study for untoward incidents (e.g., 
“Adverse Events”) occurring during the study. The Principal Investigator (and other designated 
individuals, if necessary) will conduct regular monitoring for safety concerns and provide general 
oversight for human subject safety requirements. Where necessary these occurrences will be 
evaluated for severity, attribution, and possible trends. All adverse events that are anticipated or 
described in the informed consent form will be logged appropriately and reported to the IRB on 
at least an annual basis (e.g., at continuing review). 
Any Unanticipated Problems or unexpected “Serious Adverse Events” related to the study 
intervention or affecting the risk/benefit profile of the study, will be reported to the IRB promptly, 
and, in all cases, within 10 business days of discovery. Unplanned and non-emergent deviations 
from the IRB approved protocol will be logged and reported to the IRB annually at continuing 
review; all planned deviations will be submitted as a Change in Research to the IRB for 
approval and prior to implementation. All other event reporting requirements will be followed and 
all necessary parties will be notified of events/problems encountered in the study and/or 
changes in research, in accordance with all applicable regulations and guidelines. 

Statistical Plan  
Sample Size Determination and Power 
We estimate that 1200 patients with prediabetes will be seen over the 12-month intervention 
period within each clinic (total sample of 2400 patients). Based on this sample, we estimate we 
will have 100% power to detect a change in rate of referral to DPPs from 0% to 25%. Additionally, 
we estimate that we will have 100% power to detect a change in documented prediabetes 
diagnosis from 10% (baseline rate estimated from Johns Hopkins data) to 34% (national estimate 
of the prevalence of prediabetes), follow-up lab testing completed from 50% (baseline rate 
estimated from Johns Hopkins data) to 60%, and referral to nutrition from 1% (baseline rate 
estimated from Johns Hopkins data) to 10%. In our analysis, we will assess the differences in 
trend of the outcomes in the baseline, intensive implementation, and sustainment periods. 
Primary outcome variable 
The primary outcome is whether patients with prediabetes are referred to a DPP and/or medical 
nutrition therapy and/or start metformin. 
Secondary outcome variables 
The secondary outcomes are whether patients: 1) enroll in the DPP, 2) attend a medical 
nutrition therapy visit, 3) complete follow-up glycemic testing, 4) fill metformin, 5) achieve weight 
loss ≥5% and 6) complete PCP/team follow-up visit.  
Other process outcomes we will look at include whether MyChart messages with the 
prediabetes handout are read. 
Statistical Methods 
For the analysis, we will include patients with prediabetes (identified by prediabetes registry) 
who have completed at least once PCP visit during the first 6 months of the 12-month 
intervention period. We will compare the primary outcomes and other secondary outcomes 
between the intervention and control clinics.  
We will conduct an interrupted time series analysis to evaluate the differences in trend of the 
outcomes in the baseline (V0-12m), intensive implementation (T0-T6m), and sustainment 
periods (T6m-T12m) at the patient level. We will compare these outcomes in the pre- and post-
intervention periods using logistic regression models with generalized estimating equations to 
account for repeated observations within patients. We will use multivariate logistic regression 
models to determine predictors of these outcomes adjusting for race, age, and baseline HbA1c. 
We may adjust for clinic-level characteristics, such as patient safety culture using GLINT survey 
data from 2021 and 2022 if available. We will only request aggregate data from the clinic-level 
on safety culture.  
Study Administration 
Funding Source 
Funding for this study is provided by the National Institute of Diabetes and Digestive Kidney 
Diseases under Award Number K23DK118205 (PI: Tseng). 
Subject Stipends and Payments 
Patients who complete the survey will receive a $10 gift card, either mailed to their home 
address or sent as an e-gift card based on patient preference. The last survey question will ask 
them to provide this information, which will not be linked to other responses. Clinicians who 

complete the survey will get a $25 e-gift card sent to the email address they provide. Again, 
their response to this question will not be linked to other responses.