Lung Cancer Screening Navigation for Homeless People: A Pragmatic Trial
Phase: NA
Conditions: Lung Cancer, Tobacco Use, Homelessness
Sponsor: Massachusetts General Hospital

ClinicalTrials.gov: NCT04308226 
TITLE: Lung cancer screening navigation for homeless people: A pragmatic trial 
 
PRINCIPAL INVESTIGATOR: Travis P. Baggett, MD, MPH 
 
GRANT NUMBER: 131162-RSG-17-157-01-CPPB (American Cancer Society) 
 
VERSION DATE: September 30, 2021 
 
I. BACKGROUND AND SIGNIFICANCE 
 
A. Historical background 
 
An estimated 2.3-3.5 million people experience homelessness annually in the US.1 Lung cancer 
incidence and mortality are substantially higher in this vulnerable population than in comparably-
aged non-homeless individuals.2-4 To address this disparity, we propose a pragmatic clinical trial 
to test the effect of patient navigation on lung cancer screening (LCS) completion among 
homeless-experienced adults at increased risk for lung cancer. Work that we and others have 
done suggests 2 reasons why such an intervention is needed. 
 
1) Lung cancer is a major cause of death among homeless adults and the leading cause 
of tobacco-attributable death in this population. 
 
In our study of 28,033 adults who used Boston Health Care for the Homeless Program 
(BHCHP) services in 2003-08, cancer was the second-leading cause of death and the leading 
killer of adults ≥45 years old.5 Lung cancer accounted for one-third of these cancer deaths.5 In a 
subsequent study of cancer epidemiology in this cohort, lung cancer was the leading type of 
incident cancer and the leading cause of cancer death among both men and women, with age-
standardized incidence and mortality rates exceeding those in the Massachusetts adult 
population more than 2-fold.2 An estimated 88% of 
incident lung cancer cases2 and 93% of lung cancer 
deaths6 were attributable to tobacco smoking, making 
lung cancer the leading type of smoking-attributable 
cancer and the leading cause of smoking-attributable 
death among homeless people. The excess burden 
of lung cancer in these studies of homeless adults in 
Boston was similar to that observed in studies of 
homeless and marginally housed people in Canada4 
and Glasgow3 (Table 1), suggesting that these 
disparities are not geographically constrained. This body of evidence highlights the need for 
interventions to reduce lung cancer disparities in homeless populations. One avenue for doing 
so is LCS with low-dose computed tomography (LDCT) to promote detection and potentially 
curative treatment of early-stage lung cancer. This strategy was associated with a 20% 
reduction in lung cancer mortality in the National Lung Screening Trial (NLST).7 However, 
implementing such a strategy presents formidable hurdles in the setting of homelessness. 
 
2) Homeless people have suboptimal rates of cancer screening and are diagnosed with 
screen-detectable malignancies at later stages than non-homeless people; barriers to 
implementing LCS in the setting of homelessness could exacerbate existing disparities 
in lung cancer outcomes. 
 
Table 1. Lung cancer among homeless adults 
Study location (yrs) 
SIR/SMR (95% CI) 
Boston (2003-2008)  
 
  Incidence, men 
2.30 (1.84, 2.84) 
  Incidence, women 
2.23 (1.41, 3.35) 
  Mortality, men 
2.39 (1.83, 3.08) 
  Mortality, women 
2.31 (1.26, 3.88) 
Canada (1991-2001) 
 
  Mortality, men 
1.91 (1.67, 2.18) 
  Mortality, women 
1.73 (1.26, 2.36) 
Glasgow (1975-1993)  
 
  Incidence, men 
1.64 (1.41, 1.86) 

In the 2003-08 BHCHP study of cancer epidemiology described above, homeless individuals 
were diagnosed with colorectal cancer and female breast cancer at significantly later stages 
than adults in the Massachusetts general population.2 Several studies have documented low 
rates of screening for these malignancies among homeless individuals.8-12 Given the high 
prevalence of smoking among homeless people8,13-18 and the aging of the homeless 
population,19 many homeless individuals are expected to meet the recommended criteria for 
consideration of LCS with LDCT20,21; however, as with colorectal and breast cancer screening, 
there are several obstacles to successfully implementing LCS in homeless populations. 
Homeless individuals struggling to meet basic subsistence needs may place a low priority on 
screening for asymptomatic illness22 or may feel too emotionally overwhelmed to cope with the 
possibility of an abnormal result. Additionally, despite a high burden of cancer risk factors, most 
homeless people appear to believe that their susceptibility to cancer is equal to or less than that 
of others the same age.8 Lack of insurance may pose another barrier,23,24 although this is less of 
a concern in Massachusetts and could improve elsewhere in states that expanded Medicaid 
under the Affordable Care Act. Even among insured individuals who are interested in obtaining 
LDCT screening, the process of scheduling and attending the test may prove logistically 
challenging because of difficulty navigating complex facilities and care systems,25 especially for 
the large proportions of homeless individuals with psychiatric and cognitive impairments.26-32 
Furthermore, ensuring timely follow-up of abnormal results may be challenging because of 
communication barriers and competing psychosocial issues. These barriers introduce the 
possibility that existing disparities in lung cancer mortality could worsen if homeless people are 
less able to complete LCS than other segments of the population.     
 
B. Preliminary data 
 
Our prior epidemiologic work demonstrating the burden of lung cancer disparities among 
homeless people is described above and provides the motivation for the proposed study. In 
addition, this study is informed by administrative data from BHCHP, survey and clinical trial 
studies with homeless smokers conducted by the PI (Dr. Baggett), navigation studies conducted 
by co-investigator Dr. Percac-Lima, and LCS-oriented studies conducted by co-investigators Dr. 
Park and Dr. Rigotti. Collectively, this preliminary data has demonstrated the following: 
 
1) We have the patient volume to support this study. Based on internal data from the 
BHCHP Institute, 3,443 unique individuals aged 55-77 years old were seen at any BHCHP site 
from 9/1/2015 to 9/1/2016. Of these, 53% were current smokers and 23% were former smokers, 
totaling 2,616 potentially eligible individuals seen by the program in a 12-month period. When 
extrapolated over the planned 2.5-year enrollment period, we anticipate being able to recruit 
and randomize the proposed number of 300 participants. 
 
2) We have characterized the target population. In April-July 2014, we used time-location 
sampling to conduct a survey of 306 homeless adult smokers at 5 high-volume BHCHP clinical 
sites.33-35 The response rate was 86%. One-quarter of respondents (N=78) were 55-77 years 
old. Of these, the vast majority were non-Hispanic white or black men with a high school 
degree. Seventy percent had ever experienced a traumatic head injury, 64% had used any drug 
in the past month, 39% had consumed alcohol to intoxication in the past month, 60% reported 
feeling seriously depressed, and half screened positive for PTSD. One-third reported COPD and 
17% reported cardiovascular disease. Past-month difficulty finding shelter, food, and clothing 
were common. The mean number of cigarettes per day was 12 and the mean Fagerstrom 
nicotine dependence score was 3.8 (range 0-12). These findings highlight the medical 
complexity and competing life issues of older homeless smokers and underscore the need for a 
navigation-based intervention to reduce the barriers to LCS. 

 
3) We can recruit and longitudinally retain homeless people in a clinical trial. From 
October 2015 to June 2016, we conducted a 3-arm (N=25 per arm) pilot randomized controlled 
trial testing the effect of a) contingent financial rewards for smoking abstinence, and b) text 
messaging to support smoking abstinence, against c) a shared control condition, among 
homeless smokers at BHCHP (NCT02565381). Sixty-eight percent of eligible individuals 
enrolled, and we reached our target enrollment within 6 months. Study attendance and retention 
rates were excellent. Of 14 possible assessment visits, participants attended a median of 10, 
with 97% attending ≥1 visit and 77% attending ≥7 visits. These findings demonstrate that our 
team has the expertise to conduct a behavioral treatment trial in the context of homelessness 
and to engage and retain this vulnerable population in a longitudinal fashion. This is facilitated 
by our extensive knowledge of the target population, our person-centered approach to 
participant engagement, our strong partnership with BHCHP, and the central location of BHCHP 
headquarters with respect to other homeless services. 
 
4) Our navigation intervention is based on a model that has proven effective at improving 
lung and other cancer screening among underserved patient populations in Boston. Key 
collaborator, Dr. Sanja Percac-Lima, has developed and tested navigation interventions that 
have been associated with improved cancer screening rates among diverse, low-income 
community health center patients in Boston.36,37 She conducted a randomized controlled trial 
(RCT) across 18 clinical practices in an academic primary care network evaluating the impact of 
patient navigation relative to usual care for high-risk individuals who were overdue for breast, 
colorectal, and/or cervical cancer screening.38 Patients assigned to navigation were significantly 
more likely to complete screening for breast (23.4% vs. 16.6%, p=0.009), cervical (14.4% vs. 
8.6%, p=0.007), and colorectal (13.7% vs. 7.0%, p<0.001) cancer during the follow-up period.38 
More recently, with grant support from ACS and in collaboration with Drs. Park and Rigotti, Dr. 
Percac-Lima was the principal investigator of an RCT testing the effect of patient navigation on 
chest CT completion among low-income patients eligible for LCS at 5 MGH-affiliated health 
centers in greater Boston. Preliminary analysis of data after 11 months of follow-up has shown 
that participants in the navigation arm were significantly more likely to obtain a screening lung 
CT than participants assigned to usual care (24% vs. 9%, p<0.01). The LCS navigation 
approach used in our study will be based on these successful models. 
 
C. Study rationale 
 
Mitigating disparities in lung cancer outcomes and fully realizing the potential benefits of LCS 
among homeless people will require thoughtful interventions deployed through the clinical 
programs that serve this vulnerable population. Patient navigation, a strategy for guiding 
individuals through complex health systems,39 may be a promising approach for helping 
homeless people overcome their unique barriers to LCS.40 Navigation interventions have been 
shown to improve cancer screening participation36,37,41-56 and diagnostic resolution of abnormal 
results57-63 in vulnerable populations. Patient navigation has been endorsed by the ACS64 and 
the National Cancer Institute65 as a valuable approach to reducing cancer health disparities,65 
but this approach has not been tested rigorously in a homeless health care setting. Our 
research group is well-poised to conduct such a study by leveraging our extensive clinical and 
research experience with this population and our 9-year partnership with BHCHP, an 
internationally-renowned organization that serves over 12,000 currently (84%) and formerly 
(16%) homeless people annually through dozens of clinical sites in greater Boston.66 This 
innovative community partnership has given rise to numerous impactful studies on the health of 
homeless-experienced people,2,5,6,33-35,67 including a recently pilot trial for homeless smokers 
that had brisk recruitment, high retention rates, and encouraging results (NCT02565381). 

 
II. SPECIFIC AIMS 
 
Aim 1: To determine the effect of patient navigation, added to usual care, on 1°) LCS LDCT 
completion at 6 months (26 weeks) and 2°) LCS LDCT completion at 6 months (26 weeks) and 
diagnostic follow-up of abnormal results within 1 month (4 weeks) of the recommended 
timeframe, among homeless-experienced people who are eligible for LCS. 
 
Hypothesis: Participants assigned to receive patient navigation will have significantly greater 1°) 
LCS LDCT completion at 6 months (26 weeks) and 2°) LCS LDCT completion at 6 months (26 
weeks) with timely diagnostic follow-up of abnormal results. 
 
Aim 2. To conduct post-intervention qualitative interviews of trial participants and BHCHP PCPs 
to explain and interpret the quantitative findings of the pragmatic clinical trial.  
 
Based on a sequential explanatory mixed methods approach, Aim 2 interviews will examine how 
and why participants decided whether to undergo LCS, the barriers they encountered in doing 
so, the ways in which the navigator helped them overcome these barriers, and opportunities for 
improving the intervention for future use. 
 
 
III. SUBJECT SELECTION 
 
A. Inclusion and exclusion criteria 
 
To be eligible to participate, individuals must meet all the following criteria: 
 
1) Aged 55-77 years old, assessed by self-report and verified by date of birth. 
Rationale: LCS LCDT is covered only for patients aged 55-77. 
2) Have a 30 pack-year smoking history and have smoked within the past 15 years.  
Rationale: We will be recruiting exclusively smokers because they are at the highest risk 
for lung cancer and therefore stand to receive the most benefit from a LCS. These 
smoking history parameters are consistent with current practice guidelines and Medicare 
eligibility criteria. 
3) Have a BHCHP primary care provider (PCP). 
Rationale: Patient navigation is designed to support and extend services provided by 
medical practitioners. Having a PCP will help to ensure longitudinal medical oversight of 
the LCS process and appropriate follow-up of abnormal results.   
4) Are currently or formerly homeless, assessed by self-report and defined as ever having 
experienced a time in their life where they did not have fixed, regular housing. 
Rationale: Both currently and formerly homeless individuals were included in our 
epidemiologic analysis showing a more than 2-fold higher incidence and mortality rate 
from lung cancer compared to the general Massachusetts adult population.2 BHCHP and 
most HCH programs nationally continue to serve patients after they have gained 
housing.  
5) Be proficient in English, assessed with items asking about native language and self-
reported comfort communicating in English among non-native speakers. 
Rationale: Because of a budget reduction by the funding agency, we do not have the 
resources to develop study materials or conduct in-person navigation in languages other 
than English. Additionally, the vast majority of individuals in the target population speak 
English. 

 
Individuals meeting any of the following criteria will be excluded from the study: 
 
1) A recent prior chest computed tomography (CT) imaging (in the past 12 months). 
Rationale: This study is aimed at individuals who are most likely to benefit from LCS, 
based on evidence from the National Lung Screening Trial. Potential participants that 
have recently received a chest CT will have recently been scanned for lung cancer, 
therefore an additional screening will not benefit their health outcomes.  
2) Any personal history of lung cancer, or current presentation with symptoms concerning for 
lung cancer (e.g. hemoptysis or unexplained weight loss of >15 lbs. in the past year). 
Rationale: Individuals with a history of lung cancer or symptoms concerning for lung 
cancer require surveillance or diagnostic lung imaging, respectively, and are not 
appropriate candidates for screening lung imaging, which by definition is designed for 
individuals without symptoms or history of the illness being screened for. 
3) Inability to provide informed consent, assessed with knowledge questions about the material 
presented during the informed consent process that individuals must correctly answer 
before providing informed consent to participate. 
Rationale: In this vulnerable population, we wish to take a conservative approach to the 
informed consent process to help ensure that participants fully understand the pros and 
cons of participating in the research study. 
4) PCP is the study PI (Dr. Travis Baggett). 
Rationale: BHCHP patients under the primary care of Dr. Baggett may feel unduly 
influenced to participate. In addition, since the primary study outcome (receipt of LDCT 
for LCS) requires PCP involvement, the inclusion of Dr. Baggett’s patients creates a 
conflict of interest and the potential for bias. 
 
B. Source of subjects and recruitment methods 
 
This study will be registered with ClinicalTrials.gov prior to the recruitment and enrollment of 
human subjects. All participants will be recruited from BHCHP clinical sites. BHCHP does not 
have its own IRB but instead will rely on the Partners Human Research Committee for IRB 
review through a reliance agreement initiated through SMART IRB. In addition to being a faculty 
physician-investigator at Massachusetts General Hospital and Harvard Medical School, the 
study PI is the Director of Research at BHCHP and is very familiar with the clinical environment 
and patient population served by the program. 
 
Individuals must be homeless to enroll in services at BHCHP; however, some patients continue 
receiving care at the program after they are no longer homeless. An internal analysis of 
individuals seen at BHCHP in 2011 found that 16% of patients were housed, most without 
supportive services and therefore at potentially high risk for recurrent homelessness. Because 
our epidemiologic analyses demonstrating the dramatic lung cancer disparities experienced by 
BHCHP patients included both currently and formerly homeless individuals, and because of the 
often cyclic nature of homelessness, we will include both currently and formerly homeless 
individuals in the proposed study. We refer to this group collectively as “homeless-experienced.” 
Owing to the Massachusetts system of universal health insurance, about 80% of BHCHP 
patients are insured by the state Medicaid program,68 which covers LCS LDCT among eligible 
beneficiaries,69 and a sizable proportion of those remaining are covered by Medicare alone. This 
will help ensure the availability of LCS LDCT for the vast majority of potential participants. 
 
Participants will be recruited through a combination of 3 methods: 
 

1) In-person screening of patients at BHCHP clinical sites: Study personnel will screen patients 
in-person at 6 high-volume BHCHP clinic sites: a) Pine Street Inn, a 470-bed shelter where 
BHCHP operates a medical clinic 7 days/week in the men’s shelter and 6 days/week in the 
women’s shelter; b) Southampton Shelter, a 400-bed men’s shelter where BHCHP operates a 
medical clinic 7 days/week; c) Woods Mullen Shelter, a 200-bed women’s shelter where 
BHCHP operates a medical clinic 5 days/week; d) New England Center and Home for Veterans, 
a 209-bed emergency and transitional shelter where BHCHP operates a medical clinic 5 
days/week; e) St. Francis House, a daytime multiservice facility for homeless people where 
BHCHP operates a medical clinic 5 days/week; and f) Jean Yawkey Place, the BHCHP 
headquarters facility where medical, behavioral health, and dental clinics operate 5 days/week 
with an on-site pharmacy and medical respite unit. We will also screen and recruit patients at 
selected other BHCHP clinical sites with the approval of their respective site directors and 
BHCHP medical officers. BHCHP operates at dozens of smaller clinical sites in the Boston area 
that likely reach the subsets of patient population that are eligible for the INHALE Study. Our 
prior survey fieldwork with this population has given us extensive experience with tactfully 
deploying this proactive, in-person recruitment technique.33-35  In light of the COVID-19 
pandemic, BHCHP clinical sites and shelters are experiencing a significant decrease in patient 
volume and a lack of additional space to safely conduct in-person recruitment and data 
collection activities. Under these circumstances, study personnel will initially focus in-person 
screening and data collection efforts at Jean Yawkey Place, which has the highest volume of 
patients and the greatest degree of flexibility in physical space and layout. This will allow the 
study personnel to have an in-person presence at the clinic while practicing physical distancing 
and prioritizing the health and well-being of participants and study staff. If COVID-19 restrictions 
loosen and patient volume increases at shelter sites, we will expand our efforts to include the 
five additional sites, depending on COVID-19 public health guidelines and facility protocols. 
 
2) Review of BHCHP electronic records: BHCHP has a comprehensive EHR system (Epic) that 
prompts providers to assess tobacco use at every clinical encounter, facilitating determination of 
smoking history and current smoking status. Individuals with a BHCHP PCP who have been 
seen in a BHCHP clinic in the past year and who were current or former smokers at the time of 
their most recent clinical encounter will be approached in person at BHCHP clinical sites if they 
have a scheduled appointment or contacted proactively via phone (if they have listed contact 
information) by a research coordinator and screened for eligibility to participate. The BHCHP 
Chief Medical Officer has approved this recruitment strategy on behalf of all primary care 
providers at BHCHP clinical sites, who will in turn be notified about our recruitment approach 
prior to the start of the study (letter of approval in Appendix J).    
 
3) Referrals from BHCHP providers: We will advertise the study to all BHCHP providers and in 
all BHCHP clinical sites. Individuals deemed by a BHCHP provider to be potential candidates for 
LCS can be referred to the research coordinator, who will screen referred patients for eligibility 
to participate. 
 
IV. SUBJECT ENROLLMENT 
 
An integrated study schema depicting recruitment, enrollment, treatment assignment, and 
outcomes assessment has been uploaded as an attachment to this application. 
 
A. COVID-19 symptom and exposure screening 
 
BHCHP staff currently screen all patients for COVID-19 symptoms or a recent positive COVID-
19 test upon entry to BHCHP clinics and facilities. BHCHP is also providing patients with 

facemasks before entering the building. Study personnel will re-screen participants using the 
same approach before conducting any research activities in an enclosed room. If BHCHP 
ceases their COVID-19 screening procedure, study personnel will use BHCHP’s “COVID-19 
Screening Tool for People Experiencing Homelessness” to screen all participants for current 
COVID-19 symptoms and past 14-day COVID-19 exposures (i.e., travel to high risk countries or 
states; unmasked exposure to a person with COVID-19). Study staff will wear appropriate 
personal protective equipment (PPE) per MGH guidelines and policies and remain 6 feet away 
from the patient. If patient endorses any COVID-19 symptoms or high-risk exposures, study 
personnel will immediately notify a clinic staff member of the presence of a symptomatic patient 
and will not engage in any study activities. Immediately after departure of the symptomatic 
patient, study personnel will disinfect surfaces that were within 6 feet of the symptomatic patient. 
If the participant reports not having symptoms, they can be directed to the study table/interview 
room. If the study coordinator makes initial contact with a participant over the phone, before 
scheduling an in-person visit, study personnel will screen the participant within 72 hours before 
the appointment. If participants report COVID-19 symptoms or exposures, study staff will 
request participants’ permission to contact their BHCHP PCP via Epic messaging who can then 
advise the participant on next steps (e.g., testing and/or quarantine). If participants do not 
provide permission to study staff to contact their PCP, study staff will recommend that the 
participant seek care for their symptoms and/or exposure and offer to do the initial study 
procedures over the phone. If they are not interested in completing any further study procedures 
over the phone, study staff will call the participant again in 10 days to check-in and rescreen 
before attempting to schedule any study procedures in person. Participants will be advised to 
put on a facemask, regardless of symptoms, before coming in to meet with the research 
coordinator. Research personnel will instruct participants to notify them before arriving if they 
have fever or symptoms of COVID-19. 
 
B. Methods of enrollment 
 
Participants recruited through the above methods (section III.B) will be screened for eligibility 
either in-person or by phone. Prior to contacting participants, study staff will use the eligibility 
screener (Appendix A) to record information related to eligibility that was able to be collected 
during the prior review of prospective participants’ BHCHP EHR (as referenced above).  
 
Upon approaching the participants, study staff will use participant self-report to verify any 
information collected via their EHR and will collect the minimum amount of additional 
information necessary to assess and verify study eligibility. Eligible individuals identified through 
in-person screening will be offered the chance to enroll immediately. Those identified through 
phone screening will be asked to attend an in-person enrollment visit at one of clinic sites listed 
above. Participants will be asked to provide verbal informed consent before enrolling. 
 
At least six months after initial enrollment, participants who were randomized to the patient 
navigation arm of the study will be contacted via phone or approached in person at their next 
BHCHP appointment to be offered the opportunity to participate in a 45-minute qualitative 
interview. Forty participants will be interviewed in total, with purposive sampling of participants 
who did (N=20) and participants who did not (N=20) attain the primary outcome of completing a 
lung screening CT scan within six months.  
 
At approximately 6 months after the last patient participant is enrolled, providers who had at 
least one patient enrolled in the trial will be contacted via phone, email, or in person to be 
offered the opportunity to participate in a 45-minute qualitative interview. Ten participants will be 

interviewed in total, with purposive sampling to ensure that at least one provider who works at 
each of the targeted BHCHP clinic sites are interviewed.    
 
 
C. Informed consent procedures 
 
We will obtain verbal informed consent for this study. Eligible participants will be read a verbal 
consent script (Appendix B) and be presented with a study fact sheet (Appendix C) that will 
reinforce the consent script information. Depending on space availability, participant and 
research coordinator preferences, and whether in-person research activities are safe and 
permissible, informed consent will be obtained in one of the following ways: 1) “telephone booth” 
approach where the research coordinator would conduct the consent via Microsoft Teams or 
Enterprise Zoom on an encrypted laptop with the participant in a dedicated space on an 
encrypted study tablet; 2) meet in the clinic lobby, in a screened off area while maintaining at 
least 6 feet distance; 3) meet in an enclosed BHCHP clinic room while maintaining at least 6 
feet distance if safe to do so; or 4) over the phone. The research coordinator will confirm 
participants’ understanding of the consent materials with basic knowledge questions about the 
information presented to them to ensure that they have the capacity to provide informed 
consent. Individuals who are able to correctly answer these questions will be asked to give their 
verbal consent to participant, which will be recorded by the research coordinator. Participants 
who provide informed consent over the phone will be given the option to receive a copy of the 
study fact sheet via picking up in-person at the JYP clinic, via mail if the participant has a 
mailing address, via secure email, or via email without send secure after obtaining participant’s 
permission.  
 
40 participants who agree to participate in the post-intervention qualitative interviews will 
participate in a second verbal informed consent process either at least 6 months after their initial 
enrollment or sooner if the participant had completed lung cancer screening and the navigation 
intervention was terminated as a result. The research coordinator will read a separate verbal 
consent script (Appendix G) that reinforces the information presented in a fact sheet (Appendix 
F) that will be distributed to participants. The fact sheet will focus on the purpose, requirements, 
risks, and benefits of participating in the qualitative interview. The research coordinator will 
confirm participants’ understanding of the consent materials with basic knowledge questions 
about the information presented to them to ensure that they have the capacity to provide 
informed consent. Individuals who are able to correctly answer these questions will be asked to 
give their verbal consent to participant, which will be recorded by the research coordinator. 
 
Additionally, we will obtain verbal consent to participate in qualitative interviews from 10 BHCHP 
PCPs who had at least 1 patient enrolled in the trial. Similar to the participants who participate in 
the interviews, the providers will be read a verbal consent script (Appendix I) that coincides with 
a fact sheet (Appendix H) that will be distributed to them. The research coordinator will record 
the providers’ verbal consent to participate in the interview.   
 
We believe the verbal consent is justified for several reasons:  
 
1) The experimental intervention, patient navigation, is a low-risk and widely-recommended 
behavioral intervention strategy with a sound evidence base in promoting cancer screening in 
vulnerable populations. Indeed, patient navigation has been endorsed by the ACS64 and the 
National Cancer Institute65 as a valuable approach to reducing cancer health disparities,65 and is 
now part of routine care in some practice settings, including at MGH-affiliated health centers. 
 

2) The outcome that the navigator is facilitating – obtaining LDCT for LCS among individuals at 
increased risk for lung cancer – is concordant with the guideline recommendations of the 
USPSTF,20 ACS,70 and multiple other professional groups.71-74 
 
3) The study procedures present no more than minimal risk, as outlined below in section VII. 
 
In order to ascertain the primary and secondary study outcomes of LDCT completion and LDCT 
completion with timely diagnostic follow-up (see section VII.B.), we will review BHCHP and MGB 
records for LDCT results in addition to obtaining written authorization from all enrolled 
participants to obtain their health/medical records for the 14 months following their trial 
enrollment date from other Boston-area hospitals and health care facilities using a HIPAA-
compliant Release of Information (ROI) form which has been vetted by privacy officers at 
BHCHP, Boston Medical Center, and MGH (Appendix N). Participants who provide verbal 
consent during an in-person enrollment appointment will also complete the ROI form in person. 
Participants with a stable home address who complete the enrollment appointment remotely will 
be given the option to receive a pre-stamped envelope with the ROI form to have them sign and 
return back by mail to our MGH or BHCHP office.  
 
If COVID-19 prompts further restrictions around in-person research activities at BHCHP, the 
research coordinator will transition to completing the verbal consent process over the phone or 
via the HIPAA compliant video conferencing platforms, Microsoft Teams or Enterprise Zoom 
depending on each participant’s preference and access to technology. Based on feedback from 
the Boston Medical Center Compliance and Privacy Office, obtaining participant medical 
records for research purposes will continue to require written authorization regardless of current 
restrictions. Therefore, as noted previously, the research coordinator will offer participants with a 
stable home address the option to receive a pre-stamped envelope with the ROI form to sign 
and mail back. For participants who cannot receive a mailed ROI form, we will need to wait until 
in-person research restrictions are lifted. In this circumstance, once safe to do so, a research 
coordinator will either directly contact these research participants by phone or attempt to meet 
them in person at a clinic site to complete the form in person.  
 
D. Treatment assignment 
 
After providing informed consent and completing a baseline survey (see section V. A.), 
participants will be block-randomized in a 2:1 ratio to usual care with (N=200) or without 
(N=100) LCS navigation. The randomization scheme will be concealed from the study 
coordinator responsible for randomizing participants. Randomization will be stratified by 
smoking status (current/former), housing status (homeless/housed), prior discussion of lung 
cancer screening with their PCP, and primary clinical site where the patient sees their PCP (JYP 
vs. non-JYP sites) to ensure balance between study arms on these variables. We will stratify by 
smoking status (determined based on responses to the eligibility screener) because lung cancer 
risk perceptions and LCS motivations may differ between current and former smokers.75,76 
Current smoking will be defined as having smoked all or part of a cigarette in the past 30 days.77 
We will stratify by housing status based on responses to various items within the baseline 
survey because the navigation needs of formerly homeless people in housing may differ from 
those who are currently homeless. Current homelessness will be defined in the following ways: 
a) usually staying in an emergency shelter, transitional shelter, abandoned building, place of 
business, car or other vehicle, church or mission, hotel or motel, or anywhere outside during the 
past 7 days, b) usually housed in last 7 days but cannot stay in a residence for at least 14 days, 
c) usually institutionalized in the last 7 days if the admission was less than 90 days and they 
were homeless prior to admission, or d) usually institutionalized in the last 7 days if the 

admission was more than 90 days and they have no identified residence where they can stay at 
least 14 days upon discharge. These definitions are concordant with definitions of 
homelessness used by the US Department of Health and Human Services (section 330 of the 
Public Health Service Act, 42 USC § 254b)78 and by the US Department of Housing and Urban 
Development (S. 896 HEARTH Act of 2009).79 We will stratify based on prior discussion of lung 
cancer screening with their PCP (defined by an item within the baseline survey) due to the fact 
that these participants are farther along in the lung cancer screening process. Finally, we will 
stratify by the patient’s primary care clinical site since clinics may differ in their proximity to 
facilities that offer LCS or in their practice patterns around recommending and ordering LDCT 
for LCS. We will create 2 clinical site strata: 1 for JYP and one encompassing all of the 5 non-
JYP study sites described above. 
 
The 2 study arms are as follows: 
 
Arm 1: Usual care without patient navigation (N=100). Participants assigned to this arm will be 
given basic educational materials on general lung health (Appendix K) and referred back to their 
PCP to discuss whether to pursue lung cancer screening per usual practice.  
 
Arm 2: Usual care with patient navigation (N=200). Participants assigned to this arm will be 
informed about LCS, provided educational materials on LCS and patient navigation (Appendix 
L), and offered access to an LCS navigator. The navigator’s principal role is to guide 
participants through the LCS process. The navigator’s secondary role is to provide a brief 
tobacco intervention for participants who currently smoke. These roles are described below: 
 
1) LCS navigation: The navigator will introduce the concept of LCS and assist participants in 
scheduling and attending a shared decision-making (SDM) visit with their PCP to discuss the 
test in greater depth. The navigator will proactively reach out to PCPs about this via electronic 
messaging through the BHCHP EHR and make him/herself available to assist in the LCS 
process. If a PCP and a participant jointly decide to pursue LCS, the navigator will assist with 
booking the LDCT appointment at a local facility that offers this test and interprets it according to 
the Lung-RADS framework.80 BHCHP maintains strong clinical ties with Massachusetts General 
Hospital, Boston Medical Center, and several other area hospitals, enhancing the feasibility of 
referring patients to these facilities for LDCT. The navigator will work collaboratively with 
participants to reduce the barriers to LCS completion while building participants’ self-efficacy. If 
a participant has difficulty obtaining LDCT because of lack of insurance, the navigator will 
connect the participant with a BHCHP benefits specialist to enroll in health insurance under the 
state’s universal coverage system. Following LDCT, the navigator will coordinate a follow-up 
appointment with a participant’s PCP to discuss the results and arrange any necessary follow-
up testing. Throughout this process, the navigator will provide reminder phone calls about 
upcoming appointments, arrange for transportation assistance and other enabling services 
when needed, and reinforce the content and concepts covered in the LCS SDM visit through in-
person or phone contact. Data from our survey of homeless smokers at BHCHP indicate that 
over 70% have mobile phones, which will facilitate communication between the navigator and 
study participants. In addition to documenting their encounters and activities with patients for 
research data collection purposes (see section VI.A.), the navigator will document within the 
patients’ BHCHP EHR for their care teams to reference as needed. 
 
The navigator will work with each participant for up to 6 months (26 weeks) to receive the initial 
LCS LDCT scan. If a participant receives their initial LCS LDCT scan within the 6-month (26-
week) timeframe and requires follow-up diagnostic testing of abnormal results anytime sooner 
than the usual LCS LDCT screening interval of 12 months, the navigator will continue to work 

with the participant until the follow-up diagnostic testing is completed or until the participant no 
longer wishes to be navigated. 
 
2) Brief tobacco intervention: The navigator will provide a brief tobacco intervention and 
distribute educational handouts on smoking cessation (on an ad hoc basis; Appendix M) 
consistent with the “5 A’s” approach.81 Within this framework, the navigator will Ask participants 
if they currently smoke cigarettes and Advise current smokers to quit, emphasizing the 
connection between smoking and lung cancer and the importance of quitting smoking to lower 
their lung cancer risk. The navigator will then Assess current smokers’ willingness to quit and 
Assist them in accessing no-cost or low-cost smoking cessation resources, including: 
a) BHCHP PCPs, to discuss smoking cessation medications (e.g. nicotine 
replacement products, bupropion, or varenicline), which are covered by the state 
Medicaid program with a $1-3 copayment at retail pharmacies or at no charge through 
the BHCHP pharmacy. Over 80% of BHCHP patients are insured by the 
Massachusetts Medicaid program under the state’s universal health insurance 
system.68 
b) BHCHP tobacco counselors, who are formally trained in tobacco counseling and 
conduct weekly support groups at 4 BHCHP venues and individual counseling 
sessions at 5 BHCHP venues, all free of charge. 
c) The Massachusetts Smokers’ Helpline, a free and confidential phone counseling 
service, for participants with mobile phones. Participants who call the Massachusetts 
Smokers’ Helpline may receive up to 4 weeks of nicotine replacement therapy (patch, 
gum, or mini-lozenge) at no cost. 
 
The navigator will then arrange a time to follow-up with current smokers either by phone or in 
person to discuss their progress on smoking and their engagement in available services. For 
participants who undergo LDCT, the navigator will conduct a follow-up brief intervention to head 
off false reassurance about smoking if the findings are negative. Brief tobacco interventions are 
an evidence-based, effective treatment approach to promoting smoking cessation.81,82 The brief 
intervention strategy described above acknowledges the centrality of smoking cessation in 
reducing lung cancer deaths, capitalizes on the “teachable moment” afforded by the LCS 
process,83 satisfies the CMS requirements for LCS LDCT approval,21 and complements our 
pragmatic trial design by working within existing tobacco cessation resources available to the 
target population.  
 
 
V. Study Procedures 
 
A. Study visits and measurements 
 
Participants who are screened and deemed eligible to participate, whether in person or over the 
phone, will be asked to complete a research visit during which enrollment, collection of baseline 
data, and randomization to study arm will occur. Participants will meet with the research 
coordinator in person at a BHCHP clinic site to complete these activities or complete these 
activities remotely. After verbal consent and the written ROI form is completed, a study 
coordinator will meet with the participant to administer a 30-minute baseline survey. In a similar 
fashion to the verbal consent, the survey can be completed in one of the following ways 
depending on current pandemic status and/or participant/staff preferences: a) “telephone booth” 
approach where the research coordinator would conduct the survey on an encrypted laptop via 
Microsoft Teams or Enterprise Zoom with the participant in a dedicated space with an encrypted 
study tablet; b) meet in the clinic lobby in a screened off area while maintaining at least 6 feet 

distance; c) meet in an enclosed BHCHP clinic room while maintaining at least 6 feet distance of 
safe to do so; or d) remotely, either over the phone if the participant has adequate access to 
their own phone and phone plan, or over secure video conferencing (Microsoft Teams or 
Enterprise Zoom) if the participant has adequate access to the necessary technology. 
 
Participants will receive a one-time $25 gift card upon completion of the baseline survey in 
recognition of their time and effort. If participants complete the baseline survey over the phone, 
research staff will offer participants the chance to pick up the study gift card in-person at JYP or 
via mail if the participant has a mailing address. 
 
Participants with a stable home address who complete enrollment and the baseline survey over 
the phone and who are not willing to travel to JYP to sign the ROI in person, will be given the 
option to receive a pre-stamped envelope with the ROI form to have them sign and mail back to 
our MGH or BHCHP office. Participants will be mailed the $25 gift card once the research 
coordinator receives a signed ROI.  
 
Arm 2 participants will additionally have a series of ad hoc meetings with the LCS navigator as 
part of the intervention. These meetings may occur in person or over the phone. The navigator 
will be asked to log the date, time, and nature of activities carried out during these navigation 
sessions/meetings. 
 
Due to the nature of the primary outcome, which will be ascertained via medical record review, 
no formal research follow-up visit is necessary. The screening, baseline, and outcome variables 
for the study are detailed in section VI.A. 
 
40 participants in Arm 1 will participate in post-intervention interviews and be stratified according 
to whether they did (N=20) or did not (N=20) attain the primary outcome of completing a lung 
screening CAT scan within six months (26 weeks) of initial enrollment. Participants who agree to 
participate will go through a separate verbal consent process as illustrated previously. 
Interviews will occur after at least 6 months of exposure to the navigation intervention or sooner 
if the navigation intervention was terminated due to the participant completing lung cancer 
screening and requiring no additional follow-up or support. The interviews will last up to 45 
minutes and be audio recorded. The selection of qualitative participants following ascertainment 
of the primary quantitative outcome avoids introducing a treatment effect from the interviews 
while remaining temporally close enough to the LCS process to facilitate accurate recall. These 
40 participants will receive a one-time $25 gift card upon completion of the interview in 
recognition of their time and effort. 
 
Additionally, we will interview 10 BHCHP PCPs among those who had at least 1 patient enrolled 
in the trial. Providers who agree to participate will provide verbal consent as illustrated 
previously. Interviews will last up to 45 minutes and be audio recorded. Interviews will occur 
following completion of the trial (at least 6 months after the last patient participant is enrolled) to 
avoid influencing provider practice around LCS ordering and follow-up. The 10 PCPs will 
receive a one-time $25 gift card upon completion of the interview in recognition of their time and 
effort. 
 
Study personnel will follow various safety precautions to prevent COVID-19 transmission. For 
patients that are screened for eligibility over the phone and interested in scheduling an in-
person study visit, study personnel will administer a screening instrument for COVID-19 
symptoms and recent positive COVID-19 tests within 72 hours prior to the scheduled in-person 
study visit. Prior to entering BHCHP clinic buildings, per BHCHP policy, all patients are already 

required to wear a face mask and be screened for COVID-19 symptoms and recent positive 
COVID-19 tests at the door. If BHCHP ceases these screening procedures, study personnel will 
implement the same screening measures at the start of any in-person visit and will continue to 
require participants to wear a face mask while engaging with study staff. If a patient endorses 
any COVID-19 symptoms, study personnel will immediately cease study activities and notify a 
clinic staff of the presence of a symptomatic patient.  
 
If rising COVID-19 rates necessitate temporary restrictions on all in-person study activities at 
BHCHP facilities, we will transition to remotely conducting as many study activities as possible 
until the restrictions are lifted. Study personnel will be able to screen, perform verbal informed 
consent, conduct the baseline survey, perform qualitative interviews, and provide navigation 
services over the phone or by the HIPAA-compliant video conferencing platforms Microsoft 
Teams or Enterprise Zoom depending on patient preference and access to technology (i.e., 
owning a device with adequate minutes or video conferencing capabilities). Study personnel will 
always follow the MGB requirements for using Teams or Zoom with no study visits or activities 
being audio- or video-recorded within the Teams or Zoom platform. Microsoft Teams will be the 
preferred platform to use for video call study visits, but in the event of technical difficulties, study 
personnel will use Enterprise Zoom as a backup platform.  
 
B. Drugs 
 
While the LCS navigator will assist participants who currently smoke with accessing smoking 
cessation resources, neither the navigator nor study staff will provide participants with 
medications. Participants in both arms may choose to seek smoking cessation medications 
through their BHCHP PCP or other health care provider. 
 
C. Devices 
 
No devices will be used in this study. 
 
D. Procedures 
 
There are no procedures or surgical interventions in this study. Participants may elect to 
undergo LCS with LDCT after consultation with their PCP (and with the LCS navigator, for those 
in Arm 2), but the ordering and oversight of LDCTs will be handled by BHCHP PCPs as per 
usual practice for participants in both study arms.  
 
E. Data Collection 
 
We will collect all study data electronically using Partners-approved laptops or tablet devices 
with full disk encryption. Participant data will be recorded, saved, and managed using the 
Partners-hosted Research Electronic Data Capture (REDCap) program with data collection 
forms custom-designed for this study. We will also use BHCHP and MGB EHR to collect 
information from participants’ medical records that relates to their general health history, any 
charted mental health problems, and any other information that directly relates to lung cancer 
screening and smoking. The specific data elements collected at each study visit are detailed 
below in section VI.A.  
 
 
VI. BIOSTATISTICAL ANALYSIS 
 

A. Specific data variables 
 
1) Screening variables: Screening variables will include self-reported measures related to the 
inclusion and exclusion criteria for study participation. These will include the following variables, 
assessed as shown in Appendix A: 
- First and last name 
- Date of birth  
- Age 
- Preferred language 
- BHCHP PCP  
- Preferred BHCHP clinic site 
- History of homelessness 
- History or symptoms of lung cancer 
- Recent non-lung cancer or cancer treatment 
- Home oxygen use 
- Cigarette smoking history 
 
2) Contact form variables: Enrolled participants will be asked to complete a contact information 
form. This information will be valuable for following up with participants who cannot complete 
the baseline survey on the same day as enrollment, as well as for the patient navigator to aid 
with patient outreach and EHR documentation. This form will include the following variables, 
assessed as shown in Appendix O: 
- BHCHP Epic MRN (entered by the research coordinator from patient’s EHR) 
- Last 4 digits of social security number 
- Phone number (if applicable) 
- Address/location of usual nighttime residence 
- Alternative contact (who may know of participant’s whereabouts)  
- Contact in the case of an emergency 
- Participant photograph (with participant permission) to facilitate subsequent contact with 
patient navigator 
 
3) Baseline variables: Enrolled participants will be asked to complete a baseline assessment 
(Appendix D) of variables mapping to core domains of the Health Belief Model in addition to 
other key factors that could impact one or more dimensions of the Health Belief Model, as 
displayed in Table 2. 
 
4) Electronic health record variables: The following information will be collected from the review 
of patients’ BHCHP and MGB electronic health records:  
- History of care with BHCHP and BHCHP PCP prior to study enrollment 
- Comorbid health conditions. 
- Documentation of a shared decision making (SDM) appointment with PCP to discuss lung 
cancer screening.   
- Documentation of referrals for lung CT scans.  
- Documentation of completion of lung CT scans  
- Documentation of follow-up appointments with PCP that address results of lung cancer 
screening.  
- Documented smoking status (and any changes in smoking status during study enrollment).  
- Documented prescriptions to any smoking cessation medications 
- Documented insurance status and insurance type.  
 
 

 
 
 
 
 
 
Table 2. Baseline measures of study participants corresponding to Health Belief Model 
(HBM) domains and other key factors. 
HBM domains 
Measures 
Sociodemographic 
factors 
Age; sex; race/ethnicity; education; (all based on items from the 
2003 HCH User Survey23,84 and our prior survey work with 
homeless individuals33,34); homelessness onset, episodes, and 
duration1; current living situation 
Perceived lung 
cancer 
susceptibility/severity 
Perceived risk of lung cancer and smoking, perceived severity of 
lung cancer, worry about lung cancer, (all developed by Dr. Park 
for NLST)76,85;  
Cues for LCS 
Prior LCS recommendation by health care provider; prior exposure 
to LCS brochures, flyers, posters, or advertisements 
Perceived LCS 
benefits/barriers 
Lung cancer screening knowledge86; perceived benefits of quitting 
smoking76,85, comfort navigating hospital/health system; health 
insurance status23,84; competing priorities for meeting subsistence 
needs22 
Self-efficacy for LCS 
General self-efficacy scale87,88; self-efficacy for completing LDCT 
Other key factors 
Measures 
Tobacco use 
Duration of smoking; past quit attempts; current cigarettes/day; 
alternative tobacco use35,89,90, Fagerstrom Test for Nicotine 
Dependence91; stage of change92,93; Contemplation Ladder94 
COVID-19 
Comfort navigating hospital/attending medical appointment during 
COVID-19 outbreak95-97; Previous history of COVID-19 And Lung 
Infection/Pneumonia  
Comorbid conditions 
Alcohol Use Disorders Identification Test-Concise (AUDIT-C)98,99;! 
Drug Abuse Screening Test (DAST-10)100,101, and K6 screen for 
psychological distress102,103; single-item general health status (SF-
1)104,105 
 
3) Navigation log: The navigator will complete a log (Appendix E) capturing the following 
information each time he/she interacts with a participant in Arm 2. 
- Name of study staff who completes navigation activity 
- Date and time 
- Participant ID number 
- Who was contacted for navigation activity 
- Contact modality for navigation activity 
- Tasks/activities undertaken during encounter 
 
4) Qualitative interview data elements:  
 
Participant interviews: Participants will be asked to articulate their thought process in 
considering whether to pursue LCS and to identify the factors that most shaped their decision, 

including logistical, physical, or emotional barriers and facilitators. Based on our Health Belief 
Model framework (Table 2), we will prompt participants to consider the impact of the navigator 
on a) altering their perceived susceptibility to lung cancer, b) providing them with cues or 
reminders to pursue LCS, c) enhancing their self-efficacy for pursuing LCS, and d) helping them 
to overcome barriers to completing LCS. Among participants who undergo LDCT, we will 
assess their perspectives on the ease of the process, its impact on lung cancer worry, perceived 
lung cancer risk, and smoking behavior, and the need for any follow-up testing. 
 
PCP interviews: These interviews will elicit PCP perspectives on the challenges of 
implementing LCS guidelines in primary care practice for a vulnerable population and probe the 
ways in which the navigator did or did not help to reduce these challenges. We will also seek 
feedback from PCPs on ways to strengthen the integration of patient navigators into clinical care 
teams. 
 
B. Study Endpoints 
 
1) Primary outcome: The primary outcome is receipt of LDCT for LCS at 6 months (26 weeks). 
This will be based on radiology records verifying that a chest CT was performed for LCS and 
interpreted according to the Lung-RADS framework.80 To ascertain this outcome, study staff will 
examine available health records from BHCHP, MGB, and any other institution for which the 
participant signs a release of information, as described above in section IV.C. At 6 months (26 
weeks) after enrollment, radiology records will be requested/obtained from these facilities. Most 
Boston-area hospital records are accessible through Care Everywhere in the BHCHP version of 
Epic and through MGB Epic, supporting the feasibility of gathering this information in an efficient 
manner. This approach does not rely on participant self-report and therefore does not require in-
person or phone follow-up to ascertain. For those verified to have undergone LDCT for LCS 
within the 6 month (26-week) timeframe, the Lung-RADS result along with any abnormal or 
incidental findings will be recorded.  
 
2) Secondary outcome: Increasing LDCT completion will only reduce lung cancer mortality if 
individuals with abnormal results can undergo evaluation and treatment of early stage lung 
cancer in a timely fashion. In the setting of homelessness, a valid concern is whether 
participants with abnormal LDCT results can be recalled for diagnostic follow-up in a timely 
manner. To address this concern, our secondary outcome is receipt of LDCT with timely 
diagnostic follow-up of 
any abnormal results. To 
satisfy this composite 
outcome, participants 
must achieve the primary 
outcome (LDCT at 6 
months (26 weeks) and, if 
the result is abnormal, 
also obtain the next 
recommended follow-up 
test within 1 month (4 weeks) of the advised timeframe, based on the Lung-RADS framework.80 
Lung-RADS category descriptions, recommended follow-up, associated probabilities of 
malignancy, and estimated general population prevalences are shown in Table 3.104 As 
described above, we will obtain radiology records for participants who underwent LDCT for LCS 
to document the findings of the study, determine the Lung-RADS category associated with 
those findings, and ascertain the recommended diagnostic follow-up plan. Participants with 
Lung-RADS 1-2 findings do not require specific diagnostic action, but rather may continue with 
Table 3. Lung-RADS categories. 
Category 
Description 
Management 
Malignancy 
probability 
Gen. pop. 
prevalence 
1 
Negative 
Repeat LDCT 12 mos 
<1% 
90% 
2 
Benign 
3 
Probably 
benign 
Repeat LDCT 6 mos 
1-2% 
5% 
4A 
Suspicious 
Repeat LDCT 3 mos 
+/- PET/CT 
5-15% 
2% 
4B/X 
Chest CT, PET/CT, 
+/- biopsy 
>15% 
2% 
*Adapted from the American College of Radiology 

annual screening at 12 months. These individuals will automatically satisfy the secondary 
outcome. In contrast, Lung-RADS 3-4 findings signal an increased risk for malignancy and merit 
sooner-than-annual follow-up testing. These individuals will satisfy the secondary outcome only 
if they obtain the next recommended diagnostic study within 1 month (4 weeks) of the 
recommended timeframe. For example, if a participant has a Lung-RADS 3 finding for which 
follow-up LDCT in 6 months is recommended, we will assess whether this follow-up test 
occurred within 7 months (30 weeks) of the initial LDCT. If a participant has a Lung-RADS 4B/X 
finding suggesting a high suspicion for malignancy, we will assess whether the recommended 
follow-up testing occurred within 1 month (4 weeks) of the initial LDCT. The offer of delayed 
navigation to control arm participants will not interfere with this outcome because a) delayed 
navigation will be offered only to those who did not undergo an initial LCS LDCT within 6 
months (26 weeks) (i.e. the primary outcome), and b) attaining the primary outcome is 
necessary for satisfying the secondary outcome. 
 
3) Other outcomes: We will examine time to receipt of LDCT for LCS. Process outcomes 
include acceptance of navigation when offered, number of contacts with the navigator, and 
attendance of a LCS SDM visit with a BHCHP PCP. Tobacco-related outcomes include receipt 
of a prescription for any smoking cessation medication and changes in clinically-recorded 
smoking status (i.e. quitting among current smokers or relapsing among former smokers), both 
ascertained by BHCHP medical record review. We will track the frequency and types of 
abnormal findings detected on LCS LDCT, any additional diagnostic testing or therapeutic 
changes pursued in response to these findings, and the percentage of participants diagnosed 
with lung cancer (based on radiology and BHCHP and MGB records review). We will also track 
diagnostic chest CT scans obtained for reasons other than LCS. 
 
 
C. Statistical Methods 
 
Quantitative analysis: LDCT completion at 6 months (26 weeks) (1° outcome) and LDCT 
completion with timely diagnostic follow-up (2°outcome) are both binary outcomes. In the 
principal analysis, we will assess the difference between the navigation and usual care arms on 
attainment of these outcomes using the Chi-square test. We will also use logistic regression 
models to examine the associations between treatment condition and outcomes including 
clinical site and other known predictors of outcomes to increase the precision of effect 
estimates. Additional analyses will examine time to receipt of LDCT for LCS between study 
arms using time-to-event methods (log-rank tests and Cox regression models). Although we 
expect to be underpowered to detect significant interactions, we will examine whether the effect 
of navigation varies by smoking status, housing status, or clinical site in an exploratory analysis. 
 
Qualitative analysis: Qualitative interviews will be audiotaped and transcribed. We will use 
inductive content analysis methods to identify major and minor themes, and we will use 
deductive methods to strengthen, refine, and enhance understanding of identified themes.105 
Qualitative data coding will be performed by 2 trained study staff members using NVivo 11 
software. The data coders will meet regularly with Drs. Baggett and Park to discuss the 
structural thematic framework, categories, and coding plan. We will resolve discrepancies 
through discussion and comparison to raw data. Coding will continue iteratively until a high level 
of reliability (Kappa>0.80) is established. 
 
Integration with quantitative data: Based on a mixed methods approach,106 we will use the 
qualitative interview data to interpret and explain the quantitative observations from the trial. 
This will aid in better understanding why overall LDCT completion was higher or lower than 

expected and why the navigation intervention did or did not improve these outcomes. Following  
from our stratified sampling scheme, we will integrate the quantitative and qualitative data by 
assessing for thematic differences in the interview content of participants who did (N=20) and  
did not (N=20) attain the 
primary outcome. We will 
focus in particular on 
comparing and contrasting 
these two groups’ views on 
the utility of the navigator 
with respect to the Health 
Belief Model domains of 
perceived susceptibility, 
cues, self-efficacy, and 
barriers, as described 
above. We will additionally 
incorporate the quantitative 
baseline measures tapping 
these Health Belief Model 
domains into integrated 
analyses. Table 4 
illustrates the way in which these quantitative and qualitative data elements will be integrated 
and presented in a blended fashion. 
 
D. Power Analysis 
 
The sample size justification is based on the primary outcome of LCS LDCT completion at 6 
months (26 weeks). Internal BHCHP data suggests a presently negligible baseline rate of LCS 
LDCT. Allowing for improvement in this rate as LCS comes into wider practice, we will assume 
that 5% of usual care (Arm 1) participants will obtain an LDCT within 6 months (26 weeks). In 
our judgment, increasing this completion rate to 15% would represent a clinically meaningful 
change. We will have >80% power to detect such a difference with a sample size of 200 in the 
navigation arm (Arm 2) and 100 in the usual care arm (Arm 1). 
 
 
VII. RISKS AND DISCOMFORTS 
 
The potential risks and discomforts associated with this study are detailed below.  The methods 
for mitigating these risks and monitoring the safety of participants are described in section IX.b. 
 
A. Complications of surgical / non-surgical procedures 
 
Not applicable. 
 
B. Drug side effects and toxicities 
 
Study staff will not be offering any drugs or over-the-counter products to participants. 
 
C. Device complications 
 
Not applicable. 
 
Health Belief 
Model domains 
Measurement (method) 
LCS LDCT at 6 months 
Yes (N=20) 
No (N=20) 
Perceived 
susceptibility / 
severity 
Baseline survey (quan) 
Lung cancer risk perception, severity, 
and worry scores 
Post-intervention 
interview (qual) 
Quotes/themes about navigator impact 
on perceived susceptibility/severity 
Cues 
Baseline survey (quan) 
Past provider recommendation for 
LCS, exposure to LCS information 
Post-intervention 
interview (qual) 
Quotes/themes about navigator 
provision of cues for LCS 
Self-efficacy 
Baseline survey (quan) 
General and LCS-specific self-efficacy 
scores 
Post-intervention 
interview (qual) 
Quotes/themes about navigator impact 
on self-efficacy 
Perceived 
benefits / barriers 
Baseline survey (quan) 
LCS knowledge, competing 
subsistence difficulty scores 
Post-intervention 
interview (qual) 
Quotes/themes about navigator 
assistance with barriers 
Table 4. Proposed integration of quantitative and qualitative data. 

D. Psychosocial (non-medical) risks 
 
Potential risks to participants include psychological distress arising from the possibility of false-
positive CT findings leading to additional diagnostic studies or procedures. Psychological and/or 
physical distress may also be brought about by discussing smoking and/or changing smoking 
behavior. Finally, because we will collect and record identifying information (e.g. name, date of 
birth, and social security number), there is a risk to privacy if the data are compromised. Section 
IX (Monitoring and Quality Assurance) describes our methods for safeguarding the data and 
privacy of participants. The potential risks of this study are reasonable in relation to the potential 
benefits of reducing the risk of dying from lung cancer. 
 
E. Radiation risks 
 
There is a slight physical risk associated with exposure to radiation during CT scanning, 
although the “low-dose” nature of the test is designed to help mitigate this risk. For this reason, 
LDCT LCS for individuals at increased risk of lung cancer is recommended by a variety of 
professional societies since the benefits of screening for early stage cancer vastly outweigh the 
risks presented by small radiation exposures.  
 
 
VIII. POTENTIAL BENEFITS 
 
A. Potential benefits to participating individuals 
 
Potential benefits for participants include the opportunity to receive assistance in completing 
LCS, which has been associated with a 20% reduction in lung cancer mortality. Additionally, 
current smokers will be informed of and referred to various resources to help them quit smoking, 
which may confer numerous health and financial benefits. 
 
B. Potential benefits to society 
 
Considerable knowledge could be gained from this study. To our knowledge, this will be the first 
study to focus on LCS among homeless people and the first randomized trial of any cancer 
screening intervention in this population. By focusing on an understudied topic area pertaining 
to a common cause of death among homeless people, our study fills an important gap in the 
literature and could serve as a blueprint for improving cancer screening and outcomes in 
homeless health care settings, particularly in the 295 HCH programs that serve 890,000 people 
annually in the US.107 
 
 
IX. MONITORING AND QUALITY ASSURANCE 
 
A. Data monitoring 
 
All data will be collected using password-protected laptops or tablets with full disk encryption.  
We will use the Partners-hosted Research Electronic Data Capture (REDCap) application for 
data collection and management. REDCap is a secure, HIPAA compliant web-based application 
hosted by Partners HealthCare Research Computing, Enterprise Research Infrastructure & 
Services (ERIS). Because a Partners username is required for logging in to REDCap, all activity 
on study documents is electronically logged and therefore traceable.  All data will be collected 
according to a standardized protocol preprogrammed into REDCap, which has built-in functions 

providing real-time data entry validation to help ensure accuracy and completeness. Each data 
collection form will have instructions or prompts for collecting the required data elements, and 
the response fields for each item will have appropriate ranges and formats to ensure that the 
data is entered in a valid way. Participants who agree to be photographed will have their photo 
taken using the same device on which the rest of the data is collected (encrypted laptop or 
tablet). The photograph will be uploaded immediately to the REDCap database and the original 
photograph file will be permanently deleted from the device.  
 
The PI will review all study data weekly to monitor its integrity. Additionally, the PI, 
biostatistician, and/or data analyst will download the study data on a weekly basis from the 
Partners REDCap server and back it up to the PI’s SFA on the Partners network, which is 
protected by the Partners IS firewall, backed up nightly, and accessible only to authorized study 
staff. Only the minimum necessary number of study staff will have access to this data. Data 
analyses will be conducted by authorized study staff on the data files residing on the PI’s 
Partners SFA. The data will not be transferred to investigators outside the Partners system. 
 
The qualitative interviews conducted post-intervention will be recorded by a microphone 
connected directly to a password-protected, Partners-approved laptop or tablet with full-disk 
encryption. Audio files will be backed up to the PI’s SFA described above and then deleted from 
the portable device. 
 
If study activities are administered to participants using Enterprise Zoom or Microsoft Teams, 
personnel will always follow the MGB requirements for using video conferencing for research 
activities with no study visits or activities being audio- or video-recorded, with the exception of 
qualitative interviews, which will be audio-recorded with an encrypted laptop or tablet 
microphone (and not via the audio-recording capabilities within the Zoom or Teams platform) as 
described above. Study personnel will always follow the Principles of Privacy and share the 
minimum necessary amount of information.   
 
B. Safety monitoring 
 
Because of the narrow range of risks of the proposed study, there will not be a Data and Safety 
Monitoring Board for this trial. Instead, the safety of participants will be monitored by the PI on a 
continual basis. Navigators will stay in close contact with BHCHP PCPs and clinical staff to 
ensure the safety and well-being of all participants.  
 
To minimize the risk to privacy, we will adhere to the data management procedures described 
above to help ensure the safety and integrity of data collected about study participants. All 
identifying information will be saved securely within the REDCap database. Paper ROI forms 
will be scanned into the PI’s SFA and paper copies retained in a locked cabinet in the PI’s 
office. Only the minimum necessary number of study staff will have access to this data. At the 
conclusion of the study, personal identifiers will be removed from the dataset and all analyses 
will occur in a de-identified fashion. 
 
To help ensure the safety of participants, adverse events monitoring will be handled in the 
manner described below. 
 
C. Outcomes monitoring 
 
Because of the low-risk nature of the intervention, we will not conduct a formal interim analysis 
of the data nor define rules for early stopping of the trial. 

 
D. Adverse event reporting guidelines 
 
We will adhere to the Partners policy statement on “Reporting Unanticipated Problems including 
Adverse Events.”  Consistent with this policy, an adverse event will be defined as “any untoward 
or unfavorable medical occurrence in a human subject, including any abnormal sign, symptom, 
or disease, temporally associated with the subject’s participation in the research, whether or not 
considered related to the subject’s participation in the research.”  The PI and his designated 
study staff will be responsible for the monitoring of adverse events in study participants. 
 
Adverse events reported to the PI or other study staff will be documented in an adverse event 
report containing a description of the event, the date and time of onset, the date and time of 
resolution, the expectedness of the event, the relationship to the study, the seriousness of the 
event, and the action taken in response to the event. An adverse event will be deemed 
unexpected if the nature, severity, or frequency of the event is not consistent with a known or 
foreseeable risk given the research procedures, the characteristics of the subject population, or 
with an expected progression of an underlying condition. The following attribution scale will be 
used to describe the relationship of the adverse event to the study protocol: unrelated to the 
protocol, or possibly, probably, or definitely related to the protocol. A serious adverse event will 
be defined as an adverse event that results in death, is life-threatening, requires hospitalization, 
causes persistent or significant disability, or requires medical or surgical intervention. 
 
A summary safety report detailing all adverse events and their handling will be included in 
annual study progress reports to the Partners IRB and the American Cancer Society. 
Unexpected adverse events of any severity that are at least possibly related to the research and 
suggest the research puts participants at increased harm will be reported to the Partners IRB 
within 5 working days or 7 calendar days. Serious adverse events that are unexpected and at 
least possibly related to the research will be assumed to suggest that the research puts 
participants at increased harm and will be reported to the Partners IRB within the same time 
frame. Any action resulting in a temporary or permanent suspension of this study will be 
reported to the American Cancer Society’s program official. Adverse event reports and annual 
safety summaries will be documented by study ID number; personal identifiers will not be 
included in these reports. 
 
E. Protocol adherence 
 
1) Research staff: The study coordinators will be trained on the data collection protocols 
described above. Their understanding of these protocols will be assessed by asking them to 
demonstrate competency in using the REDCap data collection forms.  
 
2) LCS navigator: To ensure adherence to the navigation intervention strategy, the navigator 
will receive in-depth training on patient navigation and focused training on tobacco cessation 
counseling. 
 
      a) Navigation training: The navigator will receive training in the core skills of patient 
navigation, including establishing rapport with patients while maintaining appropriate 
professional boundaries, motivational interviewing, performing an initial assessment with 
patients to explore barriers to LCS, working with patients to overcome these barriers, educating 
patients about the LCS process, introducing the concept of shared decision-making (SDM) 
around LCS, and empowering participants to discuss the benefits and risks of LCS with their 
PCP. Training will also encompass an overview of lung cancer, the rationale behind LCS, and 

the practical steps involved in completing LDCT so that the navigator can better counsel 
patients on what to expect from the LCS process. Additionally, the navigator will be trained in 
identifying and managing logistical hurdles to completing LCS, such as insurance coverage 
lapses that may need to be remedied before LDCT is feasible. To facilitate timely follow-up of 
abnormal LDCT results, the navigator will received focused education on the American College 
of Radiology (ACR) Lung Imaging Reporting and Data System (Lung-RADS) framework.80 
Lung-RADS is a quality assurance tool designed to standardize LCS LDCT reporting and 
management recommendations, reduce confusion in LCS LDCT interpretations, and facilitate 
outcome monitoring.80 The navigator training will be based on the protocol developed for Dr. 
Percac-Lima ’s successful RCT of patient navigation for LCS among community health center 
patients (see section E). Dr. Percac-Lima, who has extensive experience in navigator training, 
will provide key components of this training and facilitate role playing sessions to reinforce skills. 
To the greatest extent possible, experienced navigators will be included in the training process. 
Depending upon prior experience, the navigator trainee will spend up to 2 weeks shadowing 
and observing an experienced navigator in the field prior to the start of the study. Refresher 
training and review of specific case scenarios will occur every 3 months throughout the study to 
ensure that the navigator is adhering faithfully to the intended roles and responsibilities.  
      b) Tobacco counseling training: The goal of the tobacco training component is to equip 
the navigator with the skills to provide a brief tobacco intervention. To achieve this goal, the 
navigator will complete an online 9-module course titled “Basic Skills for Working with Smokers,” 
sponsored by the University of Massachusetts Center for Tobacco Treatment Research & 
Training.108 This course provides an introduction to the theory and practice of working with 
smokers in a health care setting. The navigator will additionally receive 4 hours of case-based 
teaching from Dr. Baggett on practical approaches to working with homeless smokers, followed 
by 6 hours of observing a certified Tobacco Treatment Specialist interact with and counsel 
smokers about tobacco cessation. 
 
The navigator’s adherence to their intended duties will be assessed during weekly team 
meetings and through periodic audit of their navigation encounter logs. 
 

X. REFERENCES 
 
1. 
Burt MR, Aron LY, Douglas T, et al. Homelessness: Programs and the People They 
Serve: Findings of the National Survey of Homeless Assistance Providers and Clients: 
Technical Report. In. Washington, D.C.: U.S. Department of Housing and Urban 
Development, Office of Policy Development and Research; 1999. 
2. 
Baggett TP, Chang Y, Porneala BC, Bharel M, Singer DE, Rigotti NA. Disparities in 
Cancer Incidence, Stage, and Mortality at Boston Health Care for the Homeless 
Program. Am J Prev Med. 2015;49(5):694-702. 
3. 
Lamont DW, Toal FM, Crawford M. Socioeconomic deprivation and health in Glasgow 
and the west of Scotland--a study of cancer incidence among male residents of hostels 
for the single homeless. J Epidemiol Community Health. 1997;51(6):668-671. 
4. 
Hwang SW, Wilkins R, Tjepkema M, O'Campo PJ, Dunn JR. Mortality among residents 
of shelters, rooming houses, and hotels in Canada: 11 year follow-up study. BMJ. 
2009;339:b4036. 
5. 
Baggett TP, Hwang SW, O'Connell JJ, et al. Mortality among homeless adults in Boston: 
shifts in causes of death over a 15-year period. JAMA Intern Med. 2013;173(3):189-195. 
6. 
Baggett TP, Chang Y, Singer DE, et al. Tobacco-, alcohol-, and drug-attributable deaths 
and their contribution to mortality disparities in a cohort of homeless adults in Boston. 
Am J Public Health. 2015;105(6):1189-1197. 
7. 
Aberle DR, Adams AM, Berg CD, et al. Reduced lung-cancer mortality with low-dose 
computed tomographic screening. N Engl J Med. 2011;365(5):395-409. 
8. 
Chau S, Chin M, Chang J, et al. Cancer risk behaviors and screening rates among 
homeless adults in Los Angeles County. Cancer Epidemiol Biomarkers Prev. 
2002;11(5):431-438. 
9. 
Lebrun-Harris LA, Baggett TP, Jenkins DM, et al. Health status and health care 
experiences among homeless patients in federally supported health centers: findings 
from the 2009 patient survey. Health services research. 2013;48(3):992-1017. 
10. 
Asgary R, Garland V, Jakubowski A, Sckell B. Colorectal cancer screening among the 
homeless population of New York City shelter-based clinics. Am J Public Health. 
2014;104(7):1307-1313. 
11. 
Asgary R, Garland V, Sckell B. Breast Cancer Screening Among Homeless Women of 
New York City Shelter-Based Clinics. Womens Health Issues. 2014. 
12. 
Long HL, Tulsky JP, Chambers DB, et al. Cancer screening in homeless women: 
attitudes and behaviors. J Health Care Poor Underserved. 1998;9(3):276-292. 
13. 
Baggett TP, Rigotti NA. Cigarette smoking and advice to quit in a national sample of 
homeless adults. American Journal of Preventive Medicine. 2010;39(2):164-172. 
14. 
Connor SE, Cook RL, Herbert MI, Neal SM, Williams JT. Smoking cessation in a 
homeless population: there is a will, but is there a way? Journal of General Internal 
Medicine. 2002;17(5):369-372. 
15. 
Snyder LD, Eisner MD. Obstructive lung disease among the urban homeless. Chest. 
2004;125(5):1719-1725. 
16. 
Szerlip MI, Szerlip HM. Identification of cardiovascular risk factors in homeless adults. 
Am J Med Sci. 2002;324(5):243-246. 
17. 
Tsai J, Rosenheck RA. Smoking Among Chronically Homeless Adults: Prevalence and 
Correlates. Psychiatr Serv. 2012;63(6):569-576. 
18. 
Torchalla I, Strehlau V, Okoli CT, Li K, Schuetz C, Krausz M. Smoking and predictors of 
nicotine dependence in a homeless population. Nicotine Tob Res. 2011;13(10):934-942. 
19. 
Hahn JA, Kushel MB, Bangsberg DR, Riley E, Moss AR. BRIEF REPORT: the aging of 
the homeless population: fourteen-year trends in San Francisco. J Gen Intern Med. 
2006;21(7):775-778. 

20. 
Moyer VA. Screening for lung cancer: U.S. Preventive Services Task Force 
recommendation statement. Ann Intern Med. 2014;160(5):330-338. 
21. 
Jenson TS, Chin J, Ashby L, Hermansen J, Hutter JD. Decision Memo for Screening for 
Lung Cancer with Low Dose Computed Tomography (LDCT) (CAG-00439N). . In. 
Baltimore, MD: Centers for Medicare & Medicaid Services; 2015. 
22. 
Gelberg L, Gallagher TC, Andersen RM, Koegel P. Competing priorities as a barrier to 
medical care among homeless adults in Los Angeles. Am J Public Health. 
1997;87(2):217-220. 
23. 
Baggett TP, O'Connell JJ, Singer DE, Rigotti NA. The unmet health care needs of 
homeless adults: a national study. Am J Public Health. 2010;100(7):1326-1333. 
24. 
Kushel MB, Vittinghoff E, Haas JS. Factors associated with the health care utilization of 
homeless persons. JAMA. 2001;285(2):200-206. 
25. 
Weinstein LC, LaNoue M, Hurley K, Sifri R, Myers R. Using Concept Mapping to Explore 
Barriers and Facilitators to Breast Cancer Screening in Formerly Homeless Women with 
Serious Mental Illness. J Health Care Poor Underserved. 2015;26(3):908-925. 
26. 
Fazel S, Khosla V, Doll H, Geddes J. The prevalence of mental disorders among the 
homeless in western countries: systematic review and meta-regression analysis. PLoS 
Med. 2008;5(12):e225. 
27. 
Koegel P, Burnam MA, Farr RK. The prevalence of specific psychiatric disorders among 
homeless individuals in the inner city of Los Angeles. Arch Gen Psychiatry. 
1988;45(12):1085-1092. 
28. 
Brown RT, Kiely DK, Bharel M, Mitchell SL. Geriatric syndromes in older homeless 
adults. J Gen Intern Med. 2011;27(1):16-22. 
29. 
Topolovec-Vranic J, Ennis N, Colantonio A, et al. Traumatic brain injury among people 
who are homeless: a systematic review. BMC Public Health. 2012;12:1059. 
30. 
Topolovec-Vranic J, Ennis N, Howatt M, et al. Traumatic brain injury among men in an 
urban homeless shelter: observational study of rates and mechanisms of injury. CMAJ 
Open. 2014;2(2):E69-76. 
31. 
Hwang SW, Colantonio A, Chiu S, et al. The effect of traumatic brain injury on the health 
of homeless people. CMAJ. 2008;179(8):779-784. 
32. 
Oddy M, Moir JF, Fortescue D, Chadwick S. The prevalence of traumatic brain injury in 
the homeless community in a UK city. Brain Inj. 2012;26(9):1058-1064. 
33. 
Baggett TP, Campbell EG, Chang Y, Magid LM, Rigotti NA. Posttraumatic Stress 
Symptoms and Their Association With Smoking Outcome Expectancies Among 
Homeless Smokers in Boston. Nicotine Tob Res. 2015. 
34. 
Baggett TP, Rigotti NA, Campbell EG. Cost of Smoking among Homeless Adults. N Engl 
J Med. 2016;374(7):697-698. 
35. 
Baggett TP, Campbell EG, Chang Y, Rigotti NA. Other tobacco product and electronic 
cigarette use among homeless cigarette smokers. Addict Behav. 2016;60:124-130. 
36. 
Percac-Lima S, Ashburner JM, Bond B, Oo SA, Atlas SJ. Decreasing disparities in 
breast cancer screening in refugee women using culturally tailored patient navigation. J 
Gen Intern Med. 2013;28(11):1463-1468. 
37. 
Percac-Lima S, Lopez L, Ashburner JM, Green AR, Atlas SJ. The longitudinal impact of 
patient navigation on equity in colorectal cancer screening in a large primary care 
network. Cancer. 2014;120(13):2025-2031. 
38. 
Percac-Lima S, Ashburner JM, Zai AH, et al. Patient Navigation for Comprehensive 
Cancer Screening in High-Risk Patients Using a Population-Based Health Information 
Technology System: A Randomized Clinical Trial. JAMA Intern Med. 2016;176(7):930-
937. 
39. 
Freeman HP. Patient navigation: a community based strategy to reduce cancer 
disparities. J Urban Health. 2006;83(2):139-141. 

40. 
Asgary R, Naderi R, Wisnivesky J. Opt-Out Patient Navigation to Improve Breast and 
Cervical Cancer Screening Among Homeless Women. J Womens Health (Larchmt). 
2017. 
41. 
Braun KL, Thomas WL, Jr., Domingo JL, et al. Reducing cancer screening disparities in 
medicare beneficiaries through cancer patient navigation. J Am Geriatr Soc. 
2015;63(2):365-370. 
42. 
Myers RE, Sifri R, Daskalakis C, et al. Increasing colon cancer screening in primary care 
among African Americans. J Natl Cancer Inst. 2014;106(12). 
43. 
Honeycutt S, Green R, Ballard D, et al. Evaluation of a patient navigation program to 
promote colorectal cancer screening in rural Georgia, USA. Cancer. 2013;119(16):3059-
3066. 
44. 
Wang X, Fang C, Tan Y, Liu A, Ma GX. Evidence-based intervention to reduce access 
barriers to cervical cancer screening among underserved Chinese American women. J 
Womens Health (Larchmt). 2010;19(3):463-469. 
45. 
Paskett ED, Harrop JP, Wells KJ. Patient navigation: an update on the state of the 
science. CA Cancer J Clin. 2011;61(4):237-249. 
46. 
Phillips CE, Rothstein JD, Beaver K, Sherman BJ, Freund KM, Battaglia TA. Patient 
navigation to increase mammography screening among inner city women. J Gen Intern 
Med. 2010;26(2):123-129. 
47. 
Robinson-White S, Conroy B, Slavish KH, Rosenzweig M. Patient navigation in breast 
cancer: a systematic review. Cancer Nurs. 2010;33(2):127-140. 
48. 
Wells KJ, Battaglia TA, Dudley DJ, et al. Patient navigation: state of the art or is it 
science? Cancer. 2008;113(8):1999-2010. 
49. 
Chen LA, Santos S, Jandorf L, et al. A program to enhance completion of screening 
colonoscopy among urban minorities. Clin Gastroenterol Hepatol. 2008;6(4):443-450. 
50. 
Jandorf L, Braschi C, Ernstoff E, et al. Culturally targeted patient navigation for 
increasing african americans' adherence to screening colonoscopy: a randomized 
clinical trial. Cancer Epidemiol Biomarkers Prev. 2013;22(9):1577-1587. 
51. 
Lasser KE, Murillo J, Medlin E, et al. A multilevel intervention to promote colorectal 
cancer screening among community health center patients: results of a pilot study. BMC 
Fam Pract. 2009;10:37. 
52. 
Christie J, Itzkowitz S, Lihau-Nkanza I, Castillo A, Redd W, Jandorf L. A randomized 
controlled trial using patient navigation to increase colonoscopy screening among low-
income minorities. J Natl Med Assoc. 2008;100(3):278-284. 
53. 
Jandorf L, Gutierrez Y, Lopez J, Christie J, Itzkowitz SH. Use of a patient navigator to 
increase colorectal cancer screening in an urban neighborhood health clinic. J Urban 
Health. 2005;82(2):216-224. 
54. 
Lasser KE, Murillo J, Lisboa S, et al. Colorectal cancer screening among ethnically 
diverse, low-income patients: a randomized controlled trial. Archives of internal 
medicine. 2011;171(10):906-912. 
55. 
Horne HN, Phelan-Emrick DF, Pollack CE, et al. Effect of patient navigation on 
colorectal cancer screening in a community-based randomized controlled trial of urban 
African American adults. Cancer Causes Control. 2015;26(2):239-246. 
56. 
Percac-Lima S, Grant RW, Green AR, et al. A culturally tailored navigator program for 
colorectal cancer screening in a community health center: a randomized, controlled trial. 
J Gen Intern Med. 2009;24(2):211-217. 
57. 
Hoffman HJ, LaVerda NL, Young HA, et al. Patient navigation significantly reduces 
delays in breast cancer diagnosis in the District of Columbia. Cancer Epidemiol 
Biomarkers Prev. 2012;21(10):1655-1663. 

58. 
Markossian TW, Darnell JS, Calhoun EA. Follow-up and timeliness after an abnormal 
cancer screening among underserved, urban women in a patient navigation program. 
Cancer Epidemiol Biomarkers Prev. 2012;21(10):1691-1700. 
59. 
Battaglia TA, Bak SM, Heeren T, et al. Boston Patient Navigation Research Program: 
the impact of navigation on time to diagnostic resolution after abnormal cancer 
screening. Cancer Epidemiol Biomarkers Prev. 2012;21(10):1645-1654. 
60. 
Raich PC, Whitley EM, Thorland W, Valverde P, Fairclough D. Patient navigation 
improves cancer diagnostic resolution: an individually randomized clinical trial in an 
underserved population. Cancer Epidemiol Biomarkers Prev. 2012;21(10):1629-1638. 
61. 
Ramirez AG, Perez-Stable EJ, Penedo FJ, et al. Navigating Latinas with breast screen 
abnormalities to diagnosis: the Six Cities Study. Cancer. 2013;119(7):1298-1305. 
62. 
Lee JH, Fulp W, Wells KJ, Meade CD, Calcano E, Roetzheim R. Patient navigation and 
time to diagnostic resolution: results for a cluster randomized trial evaluating the efficacy 
of patient navigation among patients with breast cancer screening abnormalities, Tampa, 
FL. PLoS One. 2013;8(9):e74542. 
63. 
Lee JH, Fulp W, Wells KJ, Meade CD, Calcano E, Roetzheim R. Effect of patient 
navigation on time to diagnostic resolution among patients with colorectal cancer-related 
abnormalities. J Cancer Educ. 2014;29(1):144-150. 
64. 
American Cancer Society. Patient Navigators Help Cancer Patients Manage Care. 
https://www.cancer.org/latest-news/navigators-help-cancer-patients-manage-their-
care.html. Published February 24, 2017. Accessed March 1, 2017. 
65. 
National Cancer Institute. Patient Navigation Research Program (PNRP). U.S. 
Department of Health and Human Services, National Institutes of Health, National 
Cancer Institute. https://www.cancer.gov/about-nci/organization/crchd/disparities-
research/pnrp. Accessed March 28, 2017. 
66. 
O'Connell JJ, Oppenheimer SC, Judge CM, et al. The Boston Health Care for the 
Homeless Program: a public health framework. Am J Public Health. 2010;100(8):1400-
1408. 
67. 
Bauer LK, Brody JK, Leon C, Baggett TP. Characteristics of Homeless Adults Who Died 
of Drug Overdose: A Retrospective Record Review. J Health Care Poor Underserved. 
2016;27(2):846-859. 
68. 
Bharel M, Lin WC, Zhang J, O'Connell E, Taube R, Clark RE. Health care utilization 
patterns of homeless individuals in Boston: preparing for Medicaid expansion under the 
Affordable Care Act. Am J Public Health. 2013;103 Suppl 2:S311-317. 
69. 
Tsai D. MassHealth Transmittal Letter PHY-147. In: Office of Medicaid, Massachusetts 
Department of Health and Human Services; March 2016. 
70. 
Wender R, Fontham ET, Barrera E, Jr., et al. American Cancer Society lung cancer 
screening guidelines. CA Cancer J Clin. 2013;63(2):107-117. 
71. 
Detterbeck FC, Mazzone PJ, Naidich DP, Bach PB. Screening for lung cancer: 
Diagnosis and management of lung cancer, 3rd ed: American College of Chest 
Physicians evidence-based clinical practice guidelines. Chest. 2013;143(5 Suppl):e78S-
92S. 
72. 
Jaklitsch MT, Jacobson FL, Austin JH, et al. The American Association for Thoracic 
Surgery guidelines for lung cancer screening using low-dose computed tomography 
scans for lung cancer survivors and other high-risk groups. J Thorac Cardiovasc Surg. 
2012;144(1):33-38. 
73. 
Samet JH, Crowell R, Estepar RSJ, et al. Providing Guidance on Lung Cancer 
Screening to Patients and Physicians: An Update from the American Lung Association 
Lung Cancer Screening Committee. . In. Chicago: American Lung Association; April 30, 
2015. 

74. 
Bach PB, Mirkin JN, Oliver TK, et al. Benefits and harms of CT screening for lung 
cancer: a systematic review. JAMA. 2012;307(22):2418-2429. 
75. 
Park ER, Streck JM, Gareen IF, et al. A qualitative study of lung cancer risk perceptions 
and smoking beliefs among national lung screening trial participants. Nicotine Tob Res. 
2014;16(2):166-173. 
76. 
Park ER, Ostroff JS, Rakowski W, et al. Risk perceptions among participants undergoing 
lung cancer screening: baseline results from the National Lung Screening Trial. Ann 
Behav Med. 2009;37(3):268-279. 
77. 
Ryan H, Trosclair A, Gfroerer J. Adult current smoking: differences in definitions and 
prevalence estimates--NHIS and NSDUH, 2008. J Environ Public Health. 
2012;2012:918368. 
78. 
Health Resources and Services Administration, Bureau of Primary Health Care. 
Authorizing Legislation of the Health Center Program: Section 330 of the Public Health 
Service Act (42 USCS § 254b). 
http://bphc.hrsa.gov/policiesregulations/legislation/authorizing330.pdf. Accessed March 
28, 2017. 
79. 
U.S. Department of Housing and Urban Development. S. 896 HEARTH Act of 2009. 
https://www.hudexchange.info/resource/1717/s-896-hearth-act/. Accessed March 12, 
2017. 
80. 
American College of Radiology. Lung CT Screening Reporting and Data System (Lung-
RADS). http://www.acr.org/Quality-Safety/Resources/LungRADS. Accessed March 28, 
2017. 
81. 
Fiore MC, Jaen CR, Baker TB, et al. Treating Tobacco Use and Dependence: 2008 
Update. Clinical Practice Guideline. . In. Rockville, MD: U.S. Department of Health and 
Human Services. Public Health Service; May 2008. 
82. 
Park ER, Gareen IF, Japuntich S, et al. Primary Care Provider-Delivered Smoking 
Cessation Interventions and Smoking Cessation Among Participants in the National 
Lung Screening Trial. JAMA Intern Med. 2015;175(9):1509-1516. 
83. 
Poghosyan H, Kennedy Sheldon L, Cooley ME. The impact of computed tomography 
screening for lung cancer on smoking behaviors: a teachable moment? Cancer Nurs. 
2012;35(6):446-475. 
84. 
Greene J, Fahrney K, Byron M. Health Care for the Homeless User/Visit Surveys, RTI 
Project Number 07147.021. . In. Research Triangle Park, NC: RTI International; 2004. 
85. 
Kaufman AR, Koblitz AR, Persoskie A, et al. Factor Structure and Stability of Smoking-
Related Health Beliefs in the National Lung Screening Trial. Nicotine Tob Res. 
2016;18(3):321-329. 
86. 
Lowenstein LM, Richards VF, Leal VB, et al. A brief measure of Smokers' knowledge of 
lung cancer screening with low-dose computed tomography. Prev Med Rep. 2016;4:351-
356. 
87. 
Schwarzer R, Jerusalem M. Generalized Self-Efficacy scale. In: Weinman J, Wright S, 
Johnston M, eds. Measures in health psychology: A user’s portfolio. Causal and control 
beliefs. Windsor, UK: NFER-NELSON; 1995:35-37. 
88. 
Scholz U, Gutierrez Dona B, Sud S, Schwarzer R. Is General Self-Efficacy a Universal 
Construct? Psychometric Findings from 25 Countries. European Journal of 
Psychological Assessment. 2002;18(3):242-251. 
89. 
US Department of Commerce CB. National Cancer Institute and Food and Drug 
Administration co-sponsored Tobacco Use Supplement to the Current Population 
Survey. In. 2018-20192020. 
90. 
Kish DH, Reitzel LR, Kendzor DE, Okamoto H, Businelle MS. Characterizing Concurrent 
Tobacco Product Use Among Homeless Cigarette Smokers. Nicotine Tob Res. 2014. 

91. 
Heatherton TF, Kozlowski LT, Frecker RC, Fagerstrom KO. The Fagerstrom Test for 
Nicotine Dependence: a revision of the Fagerstrom Tolerance Questionnaire. Br J 
Addict. 1991;86(9):1119-1127. 
92. 
DiClemente CC, Prochaska JO, Fairhurst SK, Velicer WF, Velasquez MM, Rossi JS. 
The process of smoking cessation: an analysis of precontemplation, contemplation, and 
preparation stages of change. J Consult Clin Psychol. 1991;59(2):295-304. 
93. 
Snow MG, Prochaska JO, Rossi JS. Stages of change for smoking cessation among 
former problem drinkers: a cross-sectional analysis. J Subst Abuse. 1992;4(2):107-116. 
94. 
Biener L, Abrams DB. The Contemplation Ladder: validation of a measure of readiness 
to consider smoking cessation. Health Psychol. 1991;10(5):360-365. 
95. 
Wong LE, Hawkins JE, Murrell KL. Where are all the patients? Addressing Covid-19 fear 
to encourage sick patients to seek emergency care. NEJM Catalyst Innovations in Care 
Delivery. 2020. 
96. 
Toolkit P. COVID-19 Community Response Survey Guidance. In:2020. 
97. 
(C3PNO) CCoCPNO. COVID-19 Module for NIDA-Supported Cohorts Affected by HIV 
and Substance Use. In:2020. 
98. 
Bush K, Kivlahan DR, McDonell MB, Fihn SD, Bradley KA. The AUDIT alcohol 
consumption questions (AUDIT-C): an effective brief screening test for problem drinking. 
Archives of internal medicine. 1998;158(16):1789-1795. 
99. 
Bradley KA, Bush KR, Epler AJ, et al. Two brief alcohol-screening tests From the 
Alcohol Use Disorders Identification Test (AUDIT): validation in a female Veterans 
Affairs patient population. Archives of internal medicine. 2003;163(7):821-829. 
100. 
Skinner HA. The drug abuse screening test. Addictive behaviors. 1982;7(4):363-371. 
101. 
Yudko E, Lozhkina O, Fouts A. A comprehensive review of the psychometric properties 
of the Drug Abuse Screening Test. Journal of substance abuse treatment. 
2007;32(2):189-198. 
102. 
Kessler RC, Andrews G, Colpe LJ, et al. Short screening scales to monitor population 
prevalences and trends in non-specific psychological distress. Psychological medicine. 
2002;32(6):959-976. 
103. 
Kessler RC, Barker PR, Colpe LJ, et al. Screening for serious mental illness in the 
general population. Arch Gen Psychiatry. 2003;60:184-189. 
104. 
American College of Radiology. Lung-RADS Version 1.0 Assessment Categories. 
Available at http://www.acr.org/Quality-Safety/Resources/LungRADS. In:April 28, 2014. 
105. 
Elo S, Kyngas H. The qualitative content analysis process. J Adv Nurs. 2008;62(1):107-
115. 
106. 
Creswell JW, Plano Clark VL. Chapter 3: Choosing a Mixed Methods Design. In: 
Designing and Conducting Mixed Methods Research. 2nd ed. Los Angeles: Sage; 
2011:53-106. 
107. 
Health Resources and Services Administration, U.S. Department of Health & Human 
Services. 2015 Health Center Data: National Health Care for the Homeless Program 
Grantee Data. https://bphc.hrsa.gov/uds/datacenter.aspx?year=2015&fd=ho. Accessed 
March 16, 2017. 
108. 
Center for Tobacco Treatment Research & Training, University of Massachusetts 
Medical School. Basic Skills for Working with Smokers - Online Course. 
http://www.umassmed.edu/tobacco/training/basicskills_online/. Accessed March 28, 
2017.