Using Data to Achieve Surgical Health Equity in the Community
Phase: NA
Conditions: Gallbladder Disease
Sponsor: University of Pennsylvania

 
 
 
 
 
 
Using Data to Achieve Surgical Health Equity in the Community 
 
 
Principal Investigator: Rachel Kelz, MD 
 
 
IRB# 852524 
 
Study Protocol 
 
Version Date: 11/22/2022 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

PROJECT ABSTRACT  
Gallbladder disease (GBD) is extremely common, affecting 10% to 20% of adults in the United States with a 
prevalence as high as 70% in specific ethnic groups. Delayed treatment often leads to emergency surgery. 
Emergent cholecystectomy results in increased morbidity, mortality, length of stay, and higher costs when 
compared to elective cholecystectomy. Black and Hispanic patients, non-English primary language speakers, 
and those living in areas of greater social vulnerability are at increased risk of emergent GB surgery. Black 
patients with established primary care providers within the Penn Medicine Primary Care Service Line are more 
likely to undergo emergent (vs elective) cholecystectomy than White patients (Black: 65% (76/117); White, 41% 
(125/303); p<0.001). To address this disparity, we propose the following specific aims: 1) To examine racial 
disparities of patients with symptomatic GBD with attention to conditional effects of social vulnerabilities (SV), 
and 2) to compare the effectiveness of telemedicine consultation for symptomatic GBD in patients with SV to 
usual care. The first aim will be an observational study of Penn Medicine data using regression to adjust for 
potential confounders, and interaction terms to examine the conditional effects of SV factors.  For aim 2, we will 
perform a pilot study of telemedicine consultation. These results will provide data to develop evidence-based 
solutions to disparities within Penn Medicine and to serve as preliminary data for a subsequent R01 or PCORI 
grant to address surgical disparities in patients with symptomatic GBD. 
 
 
 

PROJECT DESCRIPTION  
AIMS AND SIGNIFICANCE 
Gallbladder (GB) disease is extremely common, affecting 10% to 20% of White adults in the United States with 
the prevalence rising as high as 70% in specific ethnic groups. [1] Up to 5% of patients with gallstone disease 
become symptomatic within 1-year. [2] The incidence is greatest among obese people placing patients from 
racial and ethnic minority groups and those from low-income backgrounds at the greatest risk of disease. [3] 
Elective cholecystectomy is recommended for patients with symptomatic cholelithiasis or biliary colic. [4] 
Laparoscopic cholecystectomy is a safe and effective treatment that can be performed in the outpatient setting 
with complication rates ranging from 0.5-6.0%. [5] 
 
Delayed treatment for symptomatic cholelithiasis and biliary colic often results in acute cholecystitis and related 
diseases that necessitate emergency surgery. [6]  For example, patients waiting 20 weeks or more for elective 
cholecystectomy were more likely to undergo admission for emergency cholecystectomy than those waiting 
shorter times. [7]  Emergent cholecystectomy results in worse outcomes with almost two-fold higher rates of 
conversion from laparoscopic to open, increased hospital length of stay by an average of over 5 days, increased 
rates of morbidity (8.8 vs 3.7%) and mortality (2.6 vs 0.5%), and higher costs (mean charge difference over 
$6,000) when compared to elective cholecystectomy. [8-10]  
 
Black and Hispanic patients, non-English primary language speakers, and those living in areas of greater social 
vulnerability are at increased risk of emergent GB surgery when compared with White, English primary language 
speakers, and those from well-resourced communities. [11-14]  Barriers to timely consultation and surgery 
among historically marginalized communities include patient- and system-level factors. For example, work 
conflicts, limited paid time off, long clinic wait times, and limited ability to contact the surgical clinic often preclude 
the ability of patients with social vulnerabilities to seek a consultation or receive elective, operative care.[15-18] 
 
Telemedicine has been shown to save patients in travel time to clinic visits [19], time off work [20], and up to 88 
minutes of time during visits [21], when compared to traditional in-person surgical visits. Moreover, patients who 
have telemedicine visits in surgery have been shown to have similar postoperative complication rates [21, 22], 
postoperative ED utilization rates, and 30-day readmissions [23] when compared to those with traditional in-
person visits. To date, no one has examined the role of telemedicine surgical consultation as a mechanism to 
promote health equity. Timely consultation with a surgeon to address biliary colic with elective cholecystectomy 
can reduce the rate of progression of disease and the need for emergent cholecystectomy. 
 
Although early studies suggested disparities in access to telemedicine among marginalized patients, this has 
been disproven in more recent studies that have shown an increase in the use of telemedicine among Black and 
socially vulnerable surgical patients [24, 25]. As such, surgical consultations via telemedicine may serve as a 
promising aid to timely elective cholecystectomy. The Institute of Medicine and National Institutes of Health have 
established health equity as a critical area for research concentration. In preliminary data, Black patients with 
biliary colic and symptomatic cholelithiasis treated within the Primary Care Service Line (PCSL) were more likely 
to present emergently for treatment than White patients. We seek to identify differences in the care paradigms 
between these populations to find and test solutions to surgical disparities within our community. To achieve 
these goals, we will focus on the following: 
 
Aim 1: Examine racial disparities in outcomes of PCSL patients with symptomatic GB disease with 
attention to conditional effects of social vulnerabilities. Hypothesis 1.1: Black patients are less likely to 
undergo cholecystectomy in the elective setting than White patients. Hypothesis 1.2: Time to consultation will 
modify the effect of race on elective cholecystectomy. Using PennMedicine data we will perform a retrospective 
cohort study of PCSL patients diagnosed with symptomatic GB disease between Jan. 1 2020 and Sept. 30, 
2022. The primary independent variable will be race. Primary outcome will be cholecystectomy. Secondary 
outcomes will include time from referral to consultation and treatment, completion of consultation, urgency of 
operative treatment, and cost. Regression models with interaction terms will be used to evaluate effect 
modification of additional social vulnerability factors (e.g., ethnicity, primary language, insurance, income) on 
outcomes.  
 
Aim 2: Comparative effectiveness study of telemedicine consultation for symptomatic GB disease in 
patients with social vulnerability (SV).  Hypothesis 2.1: Recruitment will be feasible in the three-month pilot 
period.  Hypothesis 2.2: Time to telemedicine consultation will be shorter than in-person consultation.  We will 
perform a pilot study of telemedicine vs in-person surgical consultation for patients with SV with symptomatic GB 
disease seen in PCSL clinics between January and June 2023. Rates of surgical consultation will be compared 
between groups by consultation type. Secondary outcomes will be examined.  

Scalability Preliminary data from Penn Chart shows that more than 9,400 PCSL patients seen within the last 6 
months have a diagnosis of untreated symptomatic gallbladder disease, and less than 1000 have undergone 
appropriate treatment (see Figure). This proposal will use a robust approach to explain why patients in our 
community with symptomatic GB disease do not receive timely treatment (Aim1). Then, we will test the ability of 
telemedicine to improve timely access to surgical care (Aim2). Currently, PCSL and Emergency Medicine 
providers refer patients to in-person clinic visits with surgeons. These visits typically require at least a half day 
off from work, if not more. Since the onset of the pandemic, Penn Medicine surgical clinics have integrated 
telemedicine into routine practice. Telemedicine decreases time off from work and eliminates the need for 
transportation (two established barriers to surgical care) while promoting surgical health education, the 
establishment of trust, and ease of communication with the clinic. Patients will be randomized to a telemedicine 
preoperative surgical consultation or a traditional in-person surgical consultation. The Penn Medicine system 
has capacity for this volume of surgical referrals across the three downtown hospitals. Patients will be referred 
to the location that is most convenient for them. This proposal will pilot the use of telemedicine for patients with 
symptomatic gallbladder disease treated within the community practices of PennMedicine. We propose that, at 
scale, this initiative will encourage the development of a Penn Pathway for symptomatic cholelithiasis and 
biliary colic to improve patient and provider satisfaction and will show evidence of PennMedicine’s ability to 
eliminate unnecessary waste in the pathway to surgical health when negotiating value-based purchasing 
agreements with payers.  
 
Equity Plan and Impact  
GB disease, associated with 
obesity, 
is 
very 
common, 
especially among patients with 
social vulnerabilities [26, 27]. 
Guidelines 
recommend 
laparoscopic cholecystectomy, a 
safe and effective same day 
surgery, 
for 
patients 
with 
symptomatic cholelithiasis and 
biliary colic (SGBD). From the 
literature, we know that delays in 
care often result in emergent 
presentation 
which 
is 
significantly 
associated 
with 
increased rates of complications, 
prolonged hospitalization, and 
death.[8-10] 
 
Social vulnerability (SV) is a complex concept with many definitions that are situationally dependent. For this 
proposal, we define social vulnerability by race, ethnicity, primary language, insurance, and income, five 
components known to be associated with disparities in care for patients with SGBD. Preliminary data show that 
the majority of the Penn Medicine PCSL population with SGBD meet our criteria for SV (Black race, 21% 
(n=1978); Hispanic 6% (n=565); non-English primary language 4% (n=376); low-income neighborhood 91% 
(n=8573)). Further, in preliminary data, when examining differences across racial groups, for example, Black 
PCSL patients treated within the past 6 months at PennMedicine were more likely to undergo emergent (vs 
elective) cholecystectomy than White patients (Black: 65% (76/117); White: 41% (125/303); p<0.001). Emergent 
operations are associated with worse outcomes and greater costs. 
 
Using data abstracted from PennChart, we will conduct an observational study of patients seen within the PCSL 
and the those discharged from the Emergency Department with symptomatic cholelithiasis and biliary colic 
between Jan. 1, 2020 and Sept. 30, 2022. These data will allow us to examine quality of care in two dimensions, 
safety and efficiency, for patients treated in the community setting. While we focus our analysis on race, we will 
study the conditional effects of other dimensions of SV on quality. To date, the reasons for and impact of 
delays in treatment of symptomatic GB disease in Black patients and those with other SV within our 
PennMedicine community is unknown. To test a solution to the problems of time off work and transportation, 
we will enroll patients with SV seen in the PCSL clinics in a pilot designed to test telemedicine as a mechanism 
to improve timely access to surgical care. Health equity will be measured by rates of surgical consultation among 
patients with SV and timeliness of surgical consultation and treatment. 

RESEARCH PLAN AND METHODOLOGY  
Overall Approach To address surgical health equity in patients with gallbladder disease, we will: 1) use 
regression models with interaction terms to examine racial disparities in surgical consultation and the conditional 
effects of SV factors on this relationship, 2) examine the marginal effects of social factors on outcomes, and 3) 
test a potential solution to surgical disparities, telemedicine. The first aim will be conducted in a retrospective 
observational study. Aim two will be performed as a pilot study of Penn Primary Care Service Line patients with 
SV. For this aim, we will pragmatically assign two groups to traditional care and telemedicine consultation and 
study the resultant outcomes. (See Conceptual Model above) 
 
Research Team Our team has expertise in health services research, disparities research, general surgery and 
primary care. To conduct this innovative, scientifically rigorous mixed-methods study, we will also employ the 
services of research coordinators (DOS Clinical Trials Unit), data scientists (LDI-HEDAP), and statisticians 
(Center for Surgery and Health Economics). To ensure that the study will be conducted in a way that is 
acceptable to the community, we will recruit two patients from the PCSL to serve as advisors. Advisors will be 
compensated at $50 per hour for an estimated total of 8 hours of work. 
 
Impact This proposal has the potential to scale across practices, influence value-based purchasing agreements 
and enhance patient and clinician satisfaction. Moreover, the proposed aims will have a major impact on health 
equity by: 1) assessing the clinical and financial costs of delays, 2) identifying barriers to timely treatment, 3) 
testing a simple intervention to improve access to surgical health equity for patients with social vulnerabilities.   
 
Outcomes of PCSL Patients with Symptomatic Gallbladder Disease (AIM 1)  
 
Design A retrospective cohort study. 
 
Study Subjects and Eligibility Criteria Patients with a diagnosis of symptomatic 
cholelithiasis or biliary colic who were >18 years of age and enrolled in the Primary 
Care Service Line (PCSL) Registry in Clarity or evaluated and discharged from the 
Emergency Department (PAH, PPMC and HUP) between Jan. 1 2020 and Sept. 30, 
2022 will be eligible for inclusion (data will be obtained for January 1 2020 to Dec. 31, 
2022). The Primary Care Service Line (PCSL) covers more than 500,000 patients 
across the Penn Medicine catchment area including 12 contiguous urban, suburban, 
and rural counties in the tri-state area of PA, NJ, and DE (See Figure). The population 
is approximately 37.6% Black and 7.5% underinsured. Symptomatic cholelithiasis and 
biliary colic will be identified using International Classification of Diseases, Tenth Revision, Clinical Modification 
codes (ICD-10-CM). A 6-month “look-back” will be performed to confirm the first instance of disease. Patients 
with the following criteria will be excluded from study: 1) history of prior cholecystectomy 2) prisoners, or 3) 
contraindication to cholecystectomy including GB cancer, advanced cirrhosis and untreated coagulopathy.  
 
Data Sources and Elements Clinical data will be abstracted from Clarity and financial data from the Horizon 
Performance Manager (HPM) dataset. This will allow real-world calculations of the value of care at Penn Medicine. 
 
Definition of Social Vulnerability: Race will be the primary independent variable, given the established association 
between race and surgical disparities in the literature and preliminary data from Penn Chart. Ethnicity 
(Hispanic/non-Hispanic), primary language (English/non-English), insurance (Medicaid, Medicare, private, other) 
and low-income neighborhood (home zip code) will be identified in Clarity.  
Covariates: Age, sex, comorbidities (defined by Elixhauser et al [28] using the index PCP visit and a 6-month 
look-back period), history of cholecystectomy, GB cancer, cirrhosis, coagulopathy and diagnostic imaging (US 
and CT SCAN) information will be obtained from Clarity. ICD-10 diagnosis codes will be used for clinical 
diagnoses. Date diagnosis add to chart, date of confirmatory imaging, date of discussion of treatment, date of 
referral to a surgeon and prisoner status will be obtained via direct chart review of PCSL notes within the 3-
months following the initial diagnosis of SGBD. Access point will be designated as PCSL or Emergency Dept.. 
Clinical Outcomes: Surgical consultation will be obtained from Horizon Performance Manager (HPM) via CPT 
codes for consultation. [29] Operative treatment will be determined using CPT and ICD-10-PCS codes for 
cholecystectomy as listed in HPM (CPT 47562, CPT 47563, CPT 47600, CPT 47605, CPT 56340, CPT 56341, 
ICD10 0FB40ZX, ICD10 OFB40ZZ, ICD10 OFT40ZZ) and operative urgency (emergent/urgent vs elective) will 
be based on the admission source for the associated operative encounter. We hypothesize that Black patients 
are less likely to undergo cholecystectomy in the elective setting than White patients (H1.1), that time to 

consultation will modify the effect of race on elective cholecystectomy (H1.2), and that underinsurance (e.g., 
Medicaid) will exacerbate the effect of race on outcomes.  
Financial Outcomes: We will assign costs using data from HPM for billable encounters in the emergency 
department, inpatient setting and ambulatory procedure units with a primary diagnosis related to symptomatic 
cholelithiasis and biliary colic within 90-days of diagnosis. Permutations of cost will be assessed with 
nonparametric tests and regression. We hypothesize that costs will be higher for Black patients and impacted by 
other SV factors (H1:4). Stratified analysis will be performed by treatment group and point of access. 
 
Analytic Strategy In order to adjust for potential confounders, multivariable regression (logistic and robust) will 
be used to explain the relationship between race and outcomes. Interaction terms will be used to examine effect 
modification of social vulnerability factors on the relationship between race and outcomes. The marginal effects 
of social vulnerability factors will be calculated. All analysis will be performed using STATA Version 17 (Stata 
Corporation, College Station, TX). 
 
PRELIMINARY STUDY RESULTS and POWER CALCULATIONS 
Our preliminary data from Penn Chart demonstrate racial disparities in access to care with a greater proportion 
of Black PCSL patients undergoing emergent cholecystectomy than White patients (see Equity section). We will 
be powered at 80% with an alpha of 0.05 to detect differences between Black and White patient outcomes as 
small as 5%. Note that preliminary data shows a difference of 24% in emergent chole. 
 
Telemedicine Consultation as a Mechanism to Improve Surgical Health Equity in Benign Disease (AIM 2)  
 
Design Pragmatic pilot trial.  
 
Setting and Participants Patients ages 18+ years with symptomatic cholelithiasis or biliary colic who are a 
member of a racial or ethnic minority, not primary English speaking, from a low-income neighborhood or 
underinsured will be identified from the PCSL (see above) and Emergency Department (ED) discharges including 
referral to surgery. See Figure for exclusion criteria. After Institutional Review Board (IRB) approval, potential 
participants with a new ICD-10 code for symptomatic cholelithiasis or biliary colic seen by a PCSL provider 
between April 1, and June 30, 2023 will be identified. The diagnosis and discussion with the PCSL provider will 
be confirmed by chart review to ensure the patient is aware of their diagnosis. Then, patients will be recruited 
via the electronic health record. Nonresponses will be contacted by phone. If enrollment is lower than required, 
patients will be approached about participation at the time of the in-person PCSL or ED visit. Participation will 
be voluntary and informed consent will be obtained. For this pilot study, enrollment will proceed to a maximum 
of 25 per group. We anticipate between 2-37 eligible patients per week. Participants will receive an incentive of 
$20 for participation. Demographics and clinical information will be collected in REDCap, a HIPPA-compliant, 
secure web application for building and managing online surveys and databases. 
 
Exposure, Intervention Assignment, Covariates and Outcomes 
Exposure: Assignment to telemedicine surgical consultation (vs. usual care) during the week of diagnosis of 
symptomatic cholelithiasis or biliary colic. 
Intervention 
Assignment: 
Pragmatic 
randomization will be performed by group 
enrollment in alternating weeks. 
Covariates: Participants will be followed for 6-
months from enrollment. Data on patient 
attributes will include age, race, sex, insurance 
status, primary language and 9-digit zip code 
as a proxy for neighborhood income level. 
Clinical factors will be abstracted from the 
electronic medical record including comorbid 
conditions as defined in the Elixhauser Indices 
[28], bilirubin, liver function studies, ultrasound 
scan and CT scan results.  
Outcomes: Primary outcome will be proportion 
of patients who undergo surgical consultation. 
Surgical consultation will be determined via 
chart review including care everywhere to 

ensure capture of visits outside of Penn Medicine.  Secondary outcomes will include time to consultation, 
proportion to undergo cholecystectomy, time to surgery, and emergent/urgent vs elective operation.  
 
Data Analysis Descriptive statistics will be performed. Univariate comparisons to test hypotheses will be 
performed using the chi-square test or Fisher’s exact test for categorical data and t-test or Wilcoxon rank-sum 
for continuous data. Statistical analysis will be performed using STATA Version 17 (Stata Corporation, College 
Station, TX). Stratified analyses will be performed by race, ethnicity, primary language, median neighborhood 
income, and insurance status as permitted by sample size. 
 
PRELIMINARY STUDY RESULTS and POWER CALCULATIONS 
In addition to providing preliminary evidence of the efficacy potential of telemedicine surgical consultations, the 
goal of the pilot study is to estimate recruitment and retention rates and population variance of social vulnerability 
factors. Because we want to be powered to detect small effect sizes, (0.1≤d<0.3) where d is the standardized 
difference, we will target enrollment of 20 participants per group to achieve a power of 80%, α=0.05. [32] 
 
Limitations  
• 
The study focuses on patients already connected to primary care providers. Many patients with SV may 
not reach that point in the health system. However, in clinical practice at Penn Medicine it is not uncommon 
for patients to have insurance that allows primary care at our community sites without providing benefits for 
surgical care for nonemergency conditions. This approach to patient care exposes patients treated in our 
community to the excessive clinical and financial risks associated with emergency surgery. Because we will 
conduct an explanatory analysis of factors associated with surgical consultation and treatment, we will 
identify barriers to surgical health equity (e.g., insurance coverage) within our system. This will allow us to 
develop strategies to achieve health equity at the system level.   
• 
In Aim 1, we will not be able to assess patient preference as a reason for undertreatment. We will be able 
to identify major structural barriers to care (e.g., primary language, insurance etc.). In the pilot study, we will 
include items on patient preferences (e.g., refusal to see a surgeon or have an operation). This will allow us 
to gauge the magnitude of this problem in patients with symptomatic GB disease at Penn Medicine. If this is 
a big problem, we will have to perform additional qualitative studies to determine optimal solutions. 
• 
Telehealth consultation may not be available to the most vulnerable patients. While that was true 
historically, during the pandemic studies confirmed that telehealth was used widely, especially among those 
with social vulnerabilities. Moreover, prior to the pandemic, surgical telehealth was used effectively in our 
system. In the original study, 79% of patients were able to receive telemedicine surgical visits and only 3% 
were unable due to language or communication barriers.  
 
Future Directions  
This study will provide data to develop targeted solutions to achieve surgical health equity at Penn Medicine. For 
example, in Aim 1, if we discover that underinsurance is the large barrier to treatment, then expanded 
professional navigation may be the way forward. If mistrust of the system and fears of surgery emerge as barriers 
to treatment, then peer navigation may be important. Alternatively, if we find that time off work and transportation 
to visits preclude surgical treatment, then telemedicine consultations (and resultant elective same day surgery 
rather than emergency in-patient care), may lead us to the path to health equity. We will test this directly in Aim 
2. Improving access to care will result in improved patient and provider satisfaction. We will use this information 
to convene stakeholders within the system to build a Penn Pathway for symptomatic cholelithiasis and biliary 
colic. Further, this information will provide direction for the design of a larger trial to test multiple additional 
approaches to overcome barriers to surgical health equity within Penn Medicine that can be scaled across 
practices and even beyond the confines of our own network. These data will set the stage for high value care  
bundles to treat patients with social vulnerabilities within Penn Medicine. 
 
 

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