Pilot Trial on the Efficacy of Contingency Management for Six Months of Cannabis Abstinence Among Adolescents
Phase: NA
Conditions: Cannabis Use, Adolescent Behavior
Sponsor: Massachusetts General Hospital

Title: Pilot Trial of Contingency Management for Long-
Term Cannabis Abstinence
NCT number: 03786224
Document Date: 01/13/2020

1 
PARTNERS HUMAN RESEARCH COMMITTEE 
DETAILED PROTOCOL: Contingency Management for Six Months of Cannabis Abstinence among 
Adolescents 
Protocol #: 2018P001848 
Principal Investigator: Randi Schuster, PhD 
Version Date: 1/13/2020 
I. BACKGROUND AND SIGNIFICANCE
A. Cannabis use is common among adolescents, and will likely become even more prevalent with legalization
of recreational cannabis. Cannabis is currently the most commonly used illicit substance among adolescents in
the United States and is one of the only substances with steadily increasing prevalence estimates. In fact,
rates of adolescent cannabis use now surpass those of cigarettes by almost two-fold1 and rates of use are
approaching those of alcohol.2 Recent estimates suggest that approximately 15% of 12 to 17 year olds and
52% of 18 to 25 year olds have ever tried cannabis,2 with the rates of experimental use significantly increasing
over the course of high school (approximately 14% of 8th graders, 31% of 10th graders, 45% of 12th graders1).
Patterns of regular use are also prevalent among youth, with 6% of high school students reporting daily use
and 28% reporting monthly use.1-2
These increasing prevalence estimates may be, in part, due to the cultural context in which adolescent 
cannabis use occurs. There has been an overall decrease in perceived harm of cannabis use,1 which has likely 
contributed to an increase in social and legal permissiveness for recreational use as well as increased 
acceptability and application of medicinal cannabis.3 Massachusetts, for example, voted in favor of creating a 
legal commercial market for recreational cannabis in 2016, and dispensaries are slated to open any day. As 
many of the products sold in dispensaries are specifically marketed toward teenagers, it is probable that youth 
rates of use will increase. Further, there has been an increase in the availability of more potent cannabis 
strains, which are nearly 25 times stronger than varieties available previously.4-5  
The more prevalent usage of a more potent drug in an era of swelling cannabis acceptance is a significant 
public health concern, to the extent that there are adverse sequelae from chronic cannabis exposure. A 
growing body of research supports the notion that cannabis may be addictive. The lifetime risk for cannabis 
dependence is approximately 9%, and nearly 17% when use is initiated during teenage years.6 Although these 
cumulative dependence estimates are lower for cannabis than for other substances of abuse, the rate of 
transition from non-problematic to problematic cannabis use may occur faster than for drugs such as nicotine 
and alcohol.6 Therefore, it is not surprising that use of cannabis during adolescence is associated with several 
short- and long-term problems. For instance, cannabis intoxication has been associated with an increased risk 
for motor vehicle accidents.7-8 Additionally, use between the ages of 14 and 21 years is associated with later 
difficulties in the domains of education, employment, income as well as relationship and life satisfaction.9-10 
B. The developing adolescent brain is most vulnerable to harmful effects from cannabis. Regular cannabis
exposure during adolescence may cause greater adverse effects than later exposure due to ongoing
neuromaturation occurring well into the third decade of life. Gray matter in areas underlying higher order
cognition is last to mature, and increased myelination contributing to white matter development continues
through at least the late 20s. Cannabis use is thought to affect normal neuromaturation via effects of
tetrahydrocannabinol (THC) on endocannabinoid-guided neuromaturation and selective synaptic pruning
during adolescence. Exposure to synthetic cannabinoids or THC during adolescence but not later in life is
associated with cognitive impairments that are linked with biomarkers of aberrant neurodevelopment, including
shorter dendrites and reduced spine densities in the hippocampus. Epidemiologic studies have also reported
associations between earlier cannabis onset and poor neurocognition as well as abnormalities in brain
activation patterns.for a review see 11
C. More research is needed on the relationships between neuropsychological functioning and cannabis use.
Available reports have shown that adolescence may be a unique developmental window during which

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cannabis exerts its most profound impact on neurocognitive functioning. Even after taking into account multiple 
potential confounds, those who initiate before 18 years tend to show more pronounced impairments in visual 
attention,12 visual search efficiency,13 episodic memory,14-15 and executive functioning16-19 as well as possible 
declines in intellectual functioning.20 For example, only early age of initiation (before age 16) was predictive of 
impaired reaction times on a visual scanning task, above and beyond the effects of current age, THC plasma 
levels and cumulative lifetime cannabis exposure as compared to late onset users who were not different from 
controls.12 Similarly, Solowij and colleagues15 found that earlier age of cannabis onset was associated with 
poorer learning, retention and retrieval of novel verbal information even after adjusting for the frequency and 
amount of cannabis exposure. Further, the relationship between early cannabis use and neurocognitive 
concerns may also be accompanied by unique patterns of brain activity: earlier onset chronic cannabis users 
made more errors on a behavioral inhibition task and showed more focal activation of the middle anterior 
cingulate cortex than late onset chronic users.17 These apparent neuropsychological differences among 
individuals with earlier cannabis debut may yield important functional implications as early age of initiation is 
also associated with up to a four-fold greater risk of cannabis dependence within the first two years of use.21  
 
The persistence of cognitive deficits with abstinence has become an important area of inquiry in the last few 
years, with the goal of understanding the time course of early cognitive changes associated with intoxication 
and elucidate which cognitive impairments may be persistent.22-24 In a non-randomized trial, Hanson and 
colleagues found remittance of memory deficits after three weeks of abstinence among adolescent cannabis 
users compared to non-users. A second study, which was designed to evaluate changes in cognitive 
performance among adolescents enrolled in a randomized, placebo-controlled trial of N-acetylcysteine for 
cannabis cessation, showed improvement in verbal memory and psychomotor speed in those who were 
abstinent for four or eight weeks compared to those who continued to smoke. More recently, our group found 
that one month of cannabis abstinence was associated with improvements in verbal learning but not attention 
compared to adolescent cannabis users who continued to smoke.25 These studies provide preliminary 
evidence that abstinence is associated with improved neurocognitive function. However, several critical 
questions cannot be addressed in one-month abstinence paradigms. First, it is impossible to interpret the role 
of cannabis in affecting domains that did not improve more among abstainers compared to non-abstainers. 
Deficits may recover slower in young users due to neurodevelopmental vulnerabilities, or may represent 
permanent adverse effects of regular use in adolescence or a risk factor for use. A longer-term abstinence trial 
is necessary to tease apart whether detectable deficits at one month resolve with continued sobriety or are 
non-modifiable. Second, only longer abstinence trials are well positioned to determine whether the cognitive 
improvements measured in the laboratory translate to improved academic functioning. Addressing this gap is 
essential to public health messaging.  
 
D. Rationale for Proposed Research. This proposal addresses a critical first question: is an adaptation of the 
one-month contingency management paradigm currently employed in our ongoing study (Protocol #: 
2015P000076) effective in engendering six months of cannabis abstinence? Demonstrated feasibility and 
efficacy of the six-month paradigm will lay the foundation to subsequently test, in a fully powered randomized 
trial, whether cognition and academic functioning improves when adolescents stop using cannabis.  
 
Currently, no studies have evaluated an incentive-based abstinence intervention beyond one month among 
non-treatment seeking adolescents. The long-term goal of this line of research will address critically important 
clinical questions of the impact of cannabis use, and particularly the potential beneficial effect of long-term 
cannabis abstinence, on learning/cognition and, more importantly, real-world academic functioning in 
adolescents. That is, to understand whether six months of abstinence results in an improvement in cognitive 
performance among adolescents who use cannabis regularly. This is a highly relevant question, as the 
perception among adolescents and often their parents/guardians, is that cannabis use does not impact their 
ability to learn and perform in school. It has the potential to have profound impact on our understanding of the 
clinical effect of cannabis on cognition in young people as well on policy, given the rapidly shifting political 
landscape on cannabis use in the US that will no doubt have a strong impact on prevalence and frequency of 
adolescent cannabis use, regardless of age restrictions on purchase.  
 

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This study is a critically important first-of-its-kind investigation of the potential research utility of using 
contingency management to examine long-term changes in cannabis use with six months of abstinence. 
These pilot data will inform a later trial which will focus on testing the longitudinal relationships between 
adolescent cognition and cannabis use, questions of high and growing public health significance given 
adolescents’ increased access to cannabis with legalization. 
 
II. SPECIFIC AIMS 
This pilot study will: 
 
Phase 0 
Aim 1: Evaluate the acceptability and feasibility of a contingency management intervention for six months of 
biochemically verified cannabis abstinence in adolescents who use cannabis at least once per week and who 
are not seeking treatment. 
 
Aim 2: Compare the initial efficacy of two different, non-randomized, contingency management intervention 
payment schedules (high vs low) to determine which produces more consistent rates of long-term abstinence.  
 
Phase 1 
Aim 1: Collect preliminary data on whether six months of cannabis abstinence is associated with improvement 
in cognitive functioning among frequent adolescent cannabis users  
 
III. SUBJECT SELECTION 
 
Inclusion Criteria: 
1. Male and female adolescents who are between the ages of 13 and 20 (inclusive); 
2. Average use of cannabis at least 1 time per week during the 3 months prior to study enrollment; 
3. Cannabis use reported within 7 days of study enrollment; 
4. Willing to stop using marijuana for 6 months; 
5. No immediate plan to discontinue cannabis use; 
6. Have a parent or legal guardian who is competent and willing to provide written informed consent for 
the active study phase (if under the age of 18); 
7. Competent and willing to provide written informed assent for the active study phase (if under the age of 
18); 
8. Competent and willing to provide written informed consent (if age 18 or older); 
9. Able to communicate in English language; 
10. Have a parent/guardian who can communicate in English language; 
11. Able to commit to 26 study visits in approximately 6 months; 
12. Able to safely participate in the protocol and appropriate for outpatient level of care, in the opinion of the 
investigator. 
13. No severe developmental delays (including, but not limited to, Autism Spectrum Disorder, Intellectual 
Disability, and Down Syndrome). 
 
IV. SUBJECT ENROLLMENT 
We aim to enroll 10 participants in the Phase 0 (pilot) period of the study and 20 participants in the Phase 1 
period of the study. 
 
 
Screening 
• 
Adolescents Recruited and Enrolled from The Epiphany School and Millis, Medford, Walpole, 
Westford, and Cambridge Public Schools: Passive Consent for School-Wide Screening. Given 
the history of low response rate of studies requiring students to return parent permission forms (which 
limits the number of students who can be involved in the project and threatens the ability to generalize 
the results, thus limiting the usefulness of our research results), initial screening will largely occur as 

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part of a separate IRB protocol (Protocol #2015P000076) and directly at local, participating schools with 
passive parental consent for screening. However, active parent consent and participant assent will be 
required to enroll in the intervention component of the study. Potential participants will be identified 
through an ongoing screening process that is occurring through an already approved IRB protocol (PI: 
Randi M. Schuster, Protocol #2015P000076). A brief overview of the school screening procedures from 
our other protocol (Protocol #2015P000076), which will serve as a recruitment pipeline for the current 
study, is outlined below. The school-wide assessment will serve the purpose of characterizing the 
demographics and general behavioral profile of the schools attended by the participants. Participants 
will be recruited by MGH study staff from the MGH Center for Addiction Medicine and not by any district 
and/or school personnel. Recruitment will occur through an opt-out procedure conducted solely by 
MGH staff. Specifically, at the request of MGH staff, the participating school will contact all 
parents/guardians of 5th through 12th grade students in the school’s preferred method (e.g., through 
reverse 9-11 calls, emails, mass mailings) indicating that MGH study staff will be distributing and 
collecting a very brief and de-identified questionnaire during a designated time at school. Parents and 
guardians will be told that they can freely withdraw their child from participating in the school-wide 
assessment phase without any penalty or consequence to the child, including any impact on school or 
educational activities and that parental written consent must be provided to MGH staff for active phase 
study participation. Parents and legal guardians will be informed that this is not a study or program of 
the respective school district, including a program of the specific school. School personnel will not be 
involved in administrating or operating the study in any capacity, including answering student and/or 
parent or legal guardian inquiries regarding the study.  Parents and legal guardians will be free to 
contact the principal investigator of this study at MGH directly at any time if they have questions about 
the school-wide assessment or the specific items included on the questionnaire.  
• 
Adolescents Recruited and Enrolled from the Community: Waived Parental Consent for 
Telephone Screening. Potential participants will be recruited via online advertisements, community 
flyers (see recruitment materials), and databases of participants from other lab protocols who have 
given explicit consent to be re-contacted for new studies. Among participants who are determined 
eligible through the telephone screening, under the age of 18, and interested in participating in the 
study, parent/legal guardian contact information will be collected to obtain informed consent for the 
active study phase. No active study procedures will be conducted with potential participants prior to 
obtaining written parent/guardian informed consent and adolescent assent for those under the age of 
18 or written consent for those 18 years of age or older.  
 
A waiver of written consent for telephone screening only is requested and is justified given the 
following: 
• 
The proposed research involves no more than minimal risk to participants. During 
telephone screening, we will provide details about the study and ask potential participants if they 
have any questions or concerns about the study protocol. We will also ask participants basic 
demographic information as well as brief questions related to frequency and recency of 
cannabis use to determine eligibility. These questions are indistinguishable from questions 
asked during standard school substance use assessments. This telephone screener is 
anticipated to take no more than 10 minutes and participants are free to refuse to answer any 
questions. They will be told that all information will be kept strictly confidential and answers to 
telephone screening questions will be stored separately from any identifying information. If 
participants are interested in the study and are eligible, we will collect parent/guardian contact 
information so that we can obtain written parental consent for study enrollment. No study 
procedures will occur before written parental consent is obtained (parental consent if under the 
age of 18). We will also obtain written adolescent assent (if under the age of 18) or consent (if 
18 years of age or older) at the baseline visit, prior to the initiation of any study procedures, 
during which time we will review the study in detail. 

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• 
The waiver of consent for telephone screening will not adversely affect the rights and 
welfare of subjects. The waiver of parental consent for telephone screening only will not 
adversely impact an adolescent’s access to or the nature of any ongoing health services or 
primary care in any way nor adversely affect his/her rights or welfare. The study will be detailed 
to potential participants before any telephone screening questions are asked of them, giving 
them a chance to decline telephone screening if they are not interested in the study. They are 
also free to refuse to answer any telephone screening questions that make them feel 
uncomfortable. They will be clearly told that written parental consent and adolescent assent will 
be required for enrollment in the active study phase and that answers to phone-based questions 
are for telephone screening purposes only.  
• 
The research could not practicably be carried out with the waiver or alteration. This study 
could not be practicably carried out without a waiver of consent for telephone screening for 
adolescents under the age of 18 due to the burden that would be imposed on parents/guardians 
of potential participants that are not yet even known to be eligible for and interested in study 
participation. This study utilizes a brief, de-identified telephone screen to assess whether the 
potential participant is interested in and eligible for the study. Telephone screening questions 
are similar to questions asked in standard school substance use assessments. In our 
experience, the consent process generally takes approximately 30 minutes, while the brief 
telephone screener should only take about 10 minutes or less for most participants. Requiring 
consent for telephone screening would thus dramatically increase parent/guardian burden, and 
in many cases, this imposed burden would be unnecessary because it is not guaranteed that 
their child is interested in or eligible for the study. Due to this increased parent/guardian burden, 
we expect that requiring consent for telephone screening would greatly reduce enrollment and 
compromise the representativeness of the sample. Therefore, we are proposing to seek written 
consent only for potential participants who we know are interested in and eligible for the study. It 
is for these reasons that our study requires a waiver of consent for participant telephone 
screening for adolescents under the age of 18. 
• 
Participants and parents/guardians will be provided with additional pertinent information 
after participation. Prior to the first study visit, written parental consent will be obtained for 
participants under the age of 18 and parents/guardians will be provided with copies of the 
consent form which will fully detail the study protocol as well as any associated risks and 
benefits. They will be given contact information of key study staff if they would like more 
information. Similarly, study participants will be given a copy of the signed parental 
consent/study assent form.  
• 
The research involves no more than minimal risk to the privacy of the participants. This 
research involves no more than minimal risk to the privacy of participants. During the telephone 
screening, only basic demographics and information to determine eligibility will be collected. The 
protocol fully details our plan to protect any identifying information from improper use and 
disclosure.  
Active Study Phase  
• 
Adolescents Recruited and Enrolled from The Epiphany School and Millis, Medford, Walpole, 
Westford, and Cambridge Public Schools: Written Parental Consent and Student Assent. 
Students who expressed interest in participating in the active study phase will be contacted via 
telephone and/or email by MGH study staff directly to describe the study, and discuss their interest in 
and understanding of the proposed protocol. MGH staff will send home an informed consent form 
containing our contact information for their parent or legal guardian, to read, consider and sign. Parents 
can electronically sign the consent form and send the document back to study staff if they would prefer. 
This option will only be available if this is preferred by parents; the opportunity to meet with study staff 
in person or over the phone will be made available to all parents. Parents may reach out to MGH study 
staff with any questions or concerns. The initial study visit will be coordinated with the student over the 
phone and/or via email and he/she will be told that the signed parental consent form must be received 
from his/her parent/guardian prior to the first visit or the student must bring the signed parental consent 
form to the first visit. The active phase study procedures will not begin for any participant under the age 

6 
 
of 18 until the parental consent form is obtained. Within the consent form is a description of collection of 
saliva samples for genetic analysis; parents can decline consent for DNA without penalty on 
participation for the rest of the project. During the initial study visit, informed assent will be obtained 
from the student by a trained member of the study staff prior to administering any study procedures. As 
in the parental consent form, students will indicate on the assent form whether they permit collection 
and analysis of genetic samples. All participants will be given the opportunity to ask questions to a 
doctoral-level member of the study staff during the assent process. Contact information of key MGH 
study staff will be provided and participants (and parents/guardians) will be informed that the co-
investigators are available to answer any questions or concerns they may have about the study. All 
participants will be provided with a copy of their signed parental consent and student assent forms. 
 
Students who are interested in participating and are over 18 years old will be contacted by a member of 
study staff, who will coordinate the initial study visit. At the time of such visit, informed consent will be 
obtained by a trained member of the study staff prior to administering any study procedures. Within the 
consent form is a description of collection of saliva samples for genetic analysis; participants can 
decline consent for DNA without penalty on participation for the rest of the project. All participants will 
be given the opportunity to ask questions to a doctoral-level member of study staff during the consent 
process. Contact information of key study staff will be provided and participants will be informed that 
the co-investigators are available to answer any questions or concerns they may have about the study. 
All eligible participants will be provided with a copy of their signed consent form. 
 
Upon study enrollment to Phase 0, all participants will be assigned to either a high ($1,235) or low 
($910) contingency management payment schedule in order to collect data that informs us on the level 
of payment most likely to make long-term abstinence feasible and reliably attainable (about 80% 
abstinence). 
 
• 
Adolescents Recruited and Enrolled from the Community Under 18 Years of Age: Written 
Parental Consent and Student Assent. Parent/guardian contact information will be collected from 
potential participants who expressed interest in participating in the active study phase, who were found 
to be eligible on the telephone screen, and who are under the age of 18. Parents/guardians will be 
contacted directly by MGH staff. MGH staff will send an informed consent form directly to 
parents/guardians of potential participants under the age of 18 to read, consider, and sign. Within the 
consent form is a description of collection of saliva samples for genetic analysis; parent/guardians can 
decline consent for DNA collection without penalty on participation for the rest of the project. Along with 
the consent form, MGH staff will send parents/guardians contact information if a parent/guardian wants 
to discuss any aspects of the consent form. Parents/guardians have the option to sign the consent form 
in person, or electronically via Adobe System. Adobe System’s digital signature feature is a secure and 
commonly used method of obtaining signatures electronically. The option to meet with study staff in 
person or over the phone will be made available to all parents/guardians. Parents/guardians may reach 
out to MGH study staff with any questions or concerns at any time prior to or after signing the consent 
form. The initial study visit will be coordinated with the participant over the phone and/or via email and 
he/she will be told that the signed parental consent form must be received from his/her parent/guardian 
prior to the first visit or the participant must bring the signed parental consent form to the first visit. The 
active study phase will not begin for any participant under the age of 18 until the parental consent form 
is obtained.  
 
During the initial study visit, informed assent will be obtained from the participant by a trained member 
of the study staff prior to administering any study procedures. As in the parental consent form, 
participants will indicate on the assent form whether they permit collection and analysis of genetic 
samples. All participants will be given the opportunity to ask questions to a doctoral-level member of the 
study staff during the assent process. Contact information of key MGH study staff will be provided and 
participants (and parents/guardians) will be informed that the co-investigators are available to answer 
any questions or concerns they may have about the study. All participants as well as their 

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parents/guardians will be provided with a copy of their signed parental consent and adolescent assent 
forms. 
 
Potential Participants 18 Years of Age or Older: Potential participants who are interested in 
participating and are 18 years of age or older will work directly with MGH staff following completion of 
the telephone screen to coordinate the initial study visit. At the time of such visit, informed consent will 
be obtained by a trained member of the study staff prior to administering any study procedures. Within 
the consent form is a description of collection of saliva samples for genetic analysis; participants can 
decline consent for DNA collection without penalty on participation for the rest of the project. All 
participants will be given the opportunity to ask questions to a doctoral-level member of the study staff 
during the consent process. Contact information of key study staff will be provided and participants will 
be informed that the co-investigators are available to answer any questions or concerns they may have 
about the study. All eligible participants will be provided with a copy of their signed consent form. 
 
Upon study enrollment to Phase 0, all participants will be assigned to either a high ($1,235) or low 
($910) contingency management payment schedule in order to collect data that informs us on the level 
of payment most likely to make long-term abstinence feasible and reliably attainable (about 80% 
abstinence). 
 
Participant Withdrawal (All Participants) 
Participation is completely voluntary and participants may stop being in the study at any time or decide not to 
join the study. Similarly, parents/guardians of participants younger than 18 may withdraw their child from the 
study at any time or decide not to allow their child to participate in the active study phase. If a participant or 
parent/guardian decides not to participate, they will not be penalized in any way, and will not lose any benefits 
to which they are otherwise entitled.  
 
Confidentiality (All Participants) 
All phases and aspects of this project will be conducted according to the Declaration of Helsinki and will 
comply with HIPAA regulations. The sponsors of this research will be the only individuals who will have access 
to data on individuals that are stripped of all unique identifiers according to HIPAA guidelines. School staff and 
personnel will not have access to or receive any individual data. A Certificate of Confidentiality from the 
National Institutes of Health has also been obtained for this study. 
  
Since it is required for eligibility that written informed consent from a parent/guardian be obtained for 
participants under the age of 18, parents/guardians will be aware through reading the informed consent form 
that this study is recruiting only cannabis-using adolescents. Participants will be made aware during the 
telephone screening process that the consent form may broadly reveal their cannabis use history to their 
parent/guardian. Participants under the age of 18 who do not agree to have us send an informed consent form 
to their parent/guardian will be deemed ineligible, as parental consent is required for eligibility and enrollment 
into the study. The only information a parent/guardian will be exposed to is the fact that their child uses 
cannabis. All further information regarding nature of cannabis use (such as frequency or amount), or any other 
information collected throughout the study, will be kept strictly confidential and will follow the confidentiality 
guidelines outlined in the Confidentiality and Privacy section of the protocol (section VII). 
 
V. STUDY PROCEDURES 
Telephone Screening 
Adolescents Recruited and Enrolled from The Epiphany School and Millis, Medford, Walpole, Westford, 
and Cambridge Public Schools: Passive Consent for School-Wide Screening (Phase I). Screening will 
take place both on site at the participating schools (as part of Protocol #2015P000076), and confirmed over the 
phone. Data will be collected during the screening to determine eligibility in the study; this data will include 
general demographic items as well as basic questions related to health behavior such as frequency and 
recency of cannabis and alcohol use. All students who are not withdrawn from this study phase by their 
parents/guardians and who wish to complete the questionnaire will also complete a separate form where they 
indicate their interest in being contacted for the active study phase and provide their contact information. MGH 

8 
 
study staff will collect all school-wide questionnaires and contact information forms as well as the incomplete 
forms from uninterested students. The contact information form and the brief questionnaire will be immediately 
separated to protect individual confidentiality. Questionnaires will then be reviewed only by MGH study staff 
and all cannabis-using students who indicated a willingness to be contacted will be considered potentially 
eligible for the active study phase, pending receipt of written parental consent and student assent (see below). 
A screening log that includes a non-identifying subject ID, the date of screening, and enrollment decision or 
status (see below) will be kept for all individuals screened. 
• 
Adolescents Recruited and Enrolled from the Community: Waived Parental Consent for 
Telephone Screening: In response to community advertisements, potential participants will call the 
laboratory to inquire about details of the study and complete a brief telephone questionnaire that will 
include general demographic items as well as basic questions related to health behavior such as 
frequency and recency of cannabis and alcohol use. Eligible and interested participants under the age 
of 18 will be asked for parent/guardian contact information to coordinate obtaining written parental 
informed consent. Eligible and interested participants age 18 and older will schedule their baseline 
study visit with MGH staff and informed consent will be obtained directly from these participants at their 
baseline visit. A screening log that includes a non-identifying subject ID, the date of screening, eligibility 
status, and enrollment decision/status will be kept for all individuals screened. 
 
Active Study Phase (The Epiphany School and Millis, Medford, Walpole, Westford, and Cambridge 
Public Schools; Community) 
The active study procedures for both Phase 0 and Phase 1 will be identical with the exception of added 
cognitive assessments and parent/guardian questionnaires for Phase 1 of the study. Phase 1 will not begin 
until the completion of Phase 0. Interested participants under the age of 18 who provide informed assent and 
have a parent/guardian who provides informed consent, and participants over the age of 18 who provide 
informed consent, will be enrolled in the active phase of the study. All participants will complete identical study 
procedures.   
 
Upon study enrollment participants will be placed into either the high or low payment schedule. All participants 
will complete 26 study visits, which will be spaced across approximately six months, or 24 weeks (see Study 
Schema and Time and Events table), and will be conducted confidentially at the participant’s school or in the 
laboratory at MGH. In rare circumstances (eg. shortage of available rooms on school campus), we may 
request that study visits be conducted in a private space in the near-by public library. Parents of students 
under the age of 18 who are recruited from one of the participating schools will be notified ahead of time for 
any visits not conducted on school grounds. 
 
Scheduled Visits (Approximately 10 to 120 minutes per visit). The first week of the study will consist of 
three visits: an initial baseline visit (during which eligibility will be re-confirmed), a mid-week visit (Visit 2), and a 
visit occurring approximately 1 week following baseline (Visit 3). Participants will then complete visits occurring 
at Week 2 (Visit 4) and every week thereafter, totaling 26 scheduled visits. The main objective of Phase 0 will 
be to assess the acceptability and feasibility of a contingency management protocol for long-term abstinence 
and to pilot two competing payment schedules. Visits will therefore be brief and impose minimal burden on 
participants. All scheduled visits during this phase will only consist of self-report questionnaires, semi-
structured assessments of mood and substance use, and urine drug tests to verify abstinence. During Phase 1 
of the study, cognitive testing will take place at scheduled visits occurring at baseline (Visit 1), Week 4 (Visit 6), 
Week 8 (Visit 10), Week 12 (Visit 14), Week 16 (Visit 18), Week 20 (Visit 22), and Week 24 (Visit 26). In 
addition, parents/guardians will be asked to answer brief questionnaires about their child’s behavior and mood 
during Phase 1 at scheduled visits occurring at baseline (Visit 1), Week 4 (Visit 6), Week 12 (Visit 14), and 
Week 24 (Visit 26). 
 
At the baseline visit (Visit 1), all participants will be using cannabis as usual. At the end of baseline, all 
participants (N=20) will be asked to abstain from cannabis use for six months and will complete a behavioral 
contract26 that lists behaviors to be monitored, schedule of monitoring, and contingencies to be imposed (see 
section X for more details on payment contingencies). All compensation for attendance will be distributed at the 
end of each study visit, and will be distributed between study visits for abstinence.  

9 
 
 
Cannabis abstinence will be indexed by self-reported non-use and, given cannabis’ long half-life, by 
progressively decreasing quantitative levels of 11-nor-delta-9-THC-9-carboxylic acid (THCCOOH), the primary 
cannabis metabolite, in urine. Residual cannabinoid excretion will be differentiated from new cannabis 
exposure using a statistical model developed by Schwilke and colleagues.27 This model was empirically 
derived from urine CN-THCCOOH concentration ratios of consecutively collected specimen pairs (current 
specimen/prior specimen). This model takes into account the time between collection of specimens, which 
enhances the accuracy of prediction of new cannabis use.28-30 This formula yields an expected CN-THCCOOH 
ratio associated with specimen pairs during abstinence, and observed ratios that exceed this expected value 
are interpreted as new cannabis use.  
 
All study procedures will take place at the participant’s school or in the laboratory at MGH, with the exception 
of laboratory processing of cannabis metabolites, which will be conducted at Dominion Diagnostics. 
 
Assessment Techniques 
See Time and Events Table for a detailed schedule of assessments administered by visit and by study phase. 
 
Adolescent Questionnaires: Participants will complete self-report measures addressing the following construct 
areas: demographics; cannabis use behavior and history of cannabis use; cannabis dependence; cannabis 
motives and expectancies; cannabis withdrawal; current and past use of other substances of abuse (e.g., 
tobacco, alcohol); peer support; social networks; social integration; exposure to risky peer networks; coping; 
depressive and anxiety symptoms; delinquent behaviors; temperament; and sleep. The questionnaires are 
designed to be completed during the protocol visits and are estimated to take anywhere from 10 minutes to 45 
minutes to complete depending on the study visit. Participants will be asked to complete all questionnaires at 
the baseline visit (Visit 1). Additionally, certain measures that may be sensitive to fluctuations over a six-month 
period will also be completed at subsequent visits. Such questionnaires may include items relevant to cannabis 
withdrawal, craving, and mood. If the participant prefers, some surveys may be sent electronically via secure 
REDCap survey links to complete outside of study visits to reduce the length of visits. Participants will have the 
option to complete all surveys during visits if they choose. Participants will enter data directly into REDCap 
electronically and will initial and date at the end of each survey to indicate that they inputted this information. In 
special warranted cirumstances, participants will complete questionnaires using pen and paper and study staff 
will enter the data into REDCap on their behalf.  
 
 
Parent/Guardian Questionnaires (Phase 1 only): The parent/guardian questionnaires assess parent/guardian 
perceptions of the adolescent participant’s behavior, emotional functioning, and executive function capabilities. 
These questionnaires can be completed by the parent/guardian in-person, or sent home electronically (via 
secure REDCap survey links) or by mail. Parent/guardian questionnaires will be completed at baseline (Visit 
1), as well as Week 4 (Visit 6), Week 12 (Visit 14), and Week 24 (Visit 26); they are expected to take no more 
than 20 minutes to complete. The parent/guardian will enter data directly into REDCap electronically and will 
initial and date at the end of each survey to indicate that they inputted this information. If necessary (e.g., 
survey is sent home by mail), the parent/guardian will complete questionnaires using pen and paper and study 
staff will enter the data into REDCap on their behalf.  
 
 
Adolescent Interviews: At baseline (Visit 1), participants will complete a 20-minute semi-structured timeline 
follow-back interview. The purpose of this interview is to retrospectively create a calendar of cannabis episodes 
as well as other substances of abuse over the previous 90 days. To complete the calendar, MGH staff will work 
with adolescents to identify both the days when they used substances and the substances used on each day. 
To gather this information, staff will use a modified version of the timeline follow-back procedure that has been 
successfully used in other studies with adolescent substance users. This includes identifying important dates 
or events that stand out to the participant (e.g., start/end of school, family vacations, parties, dances, etc.). At 
all following visits, participants will complete this timeline follow-back interview but substance use will only be 
assessed in the time interval since their previous visit. Participants will also complete and the Adolescent 

10 
 
Social Network Assessment to provide a summary of how and with whom they spend their time in their 
everyday lives. We will ask them to complete this assessment at every visit as this may change throughout 
their study participation. 
 
Cognitive Testing:  
In Phase 0 of the study, we will administer a small cognitive battery to ensure that feasibility of six months of 
abstinence is not compromised by the addition of cognitive testing to Phase 1. We are proposing to administer 
the California Verbal Learning Test (CVLT-II), the Wechsler Adult Intelligence Scale (WAIS-IV), and the Rey-
Osterrieth Complex Figure Test (ROCFT), which tap into similar domains assessed in the CANTAB battery 
administered at Phase 1. These tasks are standardized and provide normative data, and will be administered 
at baseline (Visit 1), Week 4 (Visit 6), Week 12 (Visit 14), and Week 24 (Visit 26). 
 
In Phase 1 of the study, we will explore whether six months of cannabis abstinence may be associated with 
changes in neurocognitive functioning such as verbal learning/memory, attention, working memory, and 
complex decision-making. Studies show differences in these domains between cannabis users and non-
users.31-32 Additionally, the neurobiological substrates typically implicated in performance on these tasks (e.g., 
prefrontal cortex, fronto-subcortical circuitry) undergo the most protracted development during adolescence 
and may therefore be most susceptible to insults from exogenous cannabinoids.  We are proposing to do much 
of the cognitive testing with the Cambridge Neuropsychological Test Automated Battery (CANTAB). We 
specifically selected the CANTAB, which is a “state-of-the-art” cognitive battery, based on several criteria to 
address practical and methodological concerns that may arise from a longitudinal, non-laboratory study. First, 
the CANTAB has been validated in many populations (including substance using adolescents33) and normative 
data are available. The CANTAB is also administered on a small computerized touch screen tablet, which 
allows for easy portability, efficient testing of many people (essential for study feasibility), and standardized 
administration. Third, tests have been adapted from animal model paradigms to increase translatability of 
findings and tests can be analyzed based on their cognitive components to more readily define impaired and 
spared cognitive capacities. Next, neuroimaging studies are available that show reliance on neural circuitry 
implicated in cognitive functioning and addiction. Finally, the CANTAB has been validated longitudinally and 
offers the unique advantage of parallel forms for retest. The cognitive battery will be administered at the 
baseline visit (Visit 1), Week 4 (Visit 6), Week 8 (Visit 10), Week 12 (Visit 14), Week 16 (Visit 18), Week 20 
(Visit 22), and Week 24 (Visit 26).  
 
Drug Testing: Participants will provide a urine sample at all study visits to qualitatively screen for cannabis use 
as well as other substances of abuse and to quantitatively screen for amount of THC metabolites in urine.  
 
Due to the negative impact that recent outside drug or alcohol use could have on a subject’s performance in 
the cognitive testing and responses to questionnaires/interviews, subjects will be asked to refrain from the use 
of any illicit drugs or the consumption of alcohol on the day of the study visits, with the exception of 
nicotine/tobacco or caffeine. This short-term abstinence will be assessed using participant self-report at each 
visit. 
 
Phase 0 Time and Events Table 
 
V0 
V1 
V6, 14, 26 
V2-5, 7-13, 15-25 
 
PS 
BL 
Wks 4, 12, 24 
Wks 1-3, 5-11, 13-
23 
Screener 
X 
 
 
 
Background Questionnaire 
 
X 
 
 
Psychopathology Questionnaires 
 
 
 
 
Safety Monitoring—CHRT 
 
X 
X 
X 
Marijuana Questionnaires 
 
 
 
 
Dependence—CUDIT-R 
 
X 
 
 
Problems—MPS 
 
X 
 
 
Craving—MCQ-SF 
 
X 
X 
X 
Withdrawal—CWS  
 
X 
X 
X 
Motives—MMM 
 
X 
 
 

11 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Note: BL, Baseline; PS, Phone Screening; Wks, Weeks 
 
Phase 1 Time and Events Table 
 
Other Questionnaires 
 
 
 
 
Exercise – GLTEQ 
 
X 
X 
X (except V2) 
School Engagement—mSESQ 
 
X 
X 
X (except V2) 
Academic History—SHQ 
 
X 
 
 
Sleep—PSQI 
 
X 
X 
X (except V2) 
Activity Involvement—mYLSBQ 
 
X 
X 
X (except V2) 
Interviews 
 
 
 
 
Peer Network—ASNA 
 
X 
X 
X 
Timeline Follow-Back—TLFB 
 
X 
X 
X 
Cognitive Tests 
 
 
 
 
CVLT-II 
 
X 
X 
 
WAIS-IV 
 
X 
X 
 
ROCFT 
 
X 
X 
 
Lab Tests 
 
 
 
 
Urinalysis 
 
X 
X 
X 
Genetics—Saliva Sample 
 
X 
 
 
Estimated Time for Completion (mins) 
10 
120 
60 
10 
 
V0 
V1 
V2, 3, 4, 8, 10, 12, 
14, 16 
V6, 14, 
26 
V10, 18, 
22 
 
PS 
BL 
Mid-Wk, Wks 1, 
2, 6, 10, 14, 18, 22 
Wks 4, 
12, 24 
Wks 8, 
16, 20 
Screener 
X 
 
 
 
 
Background Questionnaire 
 
X 
 
 
 
Psychopathology Questionnaires 
 
 
 
 
 
Childhood Sx Checklist—Childhood ADHD 
 
X 
 
 
 
Current Sx Checklist—Current ADHD 
 
X 
 
X 
 
Current Mood—MASQ 
 
X 
 
X 
X 
Depression—CES-DC 
 
X 
 
X 
X 
Safety Monitoring—CHRT 
 
X 
X 
X 
X 
Self-Report of Personality—BASC-3 SRP 
 
X 
 
X 
 
Parent Report of Personality—BASC-3 PRS* 
 
X 
 
X 
 
Cognition Questionnaires 
 
 
 
 
 
Executive Functioning—BRIEF Self-Report 
 
X 
 
X 
 
Executive Functioning—BRIEF Parent-Report* 
 
X 
 
X 
 
Delay Discounting—MCQ 
 
X 
 
X 
X 
Peer Conformity—MISS 
 
X 
 
X 
 
General SU Questionnaires 
 
 
 
 
 
Peer Substance Use/Tolerance—PSU 
 
X 
 
 
 
Alcohol Questionnaires 
 
 
 
 
 

12 
 
 
Note: BL, Baseline; PS, Phone Screening; Wks, Weeks; * indicates questionnaires completed by 
parents/guardians. 
 
DNA Collection and Analysis 
 
DNA Collection (Saliva): DNA samples will be collected using Oragene (OGR-500) saliva kits. The samples 
will be sent to Dr. Jonathan Rosand’s laboratory at Center for Genomic Medicine (CGM) at Massachusetts 
General Hospital for DNA extraction and long-term storage (Director: Sekar Kathiersan, MD). Dr. Rosand’s 
laboratory in CGM utilizes a password protected web-based application (www.PNGUtrack.com) to interface 
with the clinical enrollment sites for sample submission. At the clinical site, samples are labeled with 2D 
barcode labels which are scanned into a sample submission module of the PNGUtrack system along with 
basic non-identifying information about the sample (e.g. sex, collection date, sample volume, shipping date, 
etc.). Samples are shipped to the laboratory where they are logged into an Oracle database (JANE) that 
serves as the central LIMS tracking database. The JANE database interacts with the PNGUtrack sample 
submission system and tracks each sample from receipt to extraction to storage. 
 
Participants may be asked to provide a second sample if a re-collect is recommended after DNA extraction (i.e. 
there is very little DNA in the sample). Participants are not required to provide another sample if they do not 
wish to do so. If a participant completed our one-month abstinence study (Protocol # 2015P000076) prior to 
enrollment in this six-month abstinence study and a DNA sample was already collected, a new sample will not 
be collected and the sample from Protocol #2015P000076 will be used for analysis.   
 
Dependence—AUDIT 
 
X 
 
 
 
Motives—DMQ  
 
X 
 
 
 
Marijuana Questionnaires 
 
 
 
 
 
Dependence—CUDIT-R 
 
X 
 
 
 
Problems—MPS 
 
X 
 
 
 
Craving—MCQ-SF 
 
X 
X 
X 
X 
Withdrawal—CWS  
 
X 
X 
X 
X 
Motives—MMM 
 
X 
 
 
 
Tobacco Questionnaires 
 
 
 
 
 
Nicotine Dependence—PSECDI 
 
X 
 
 
 
Other Questionnaires 
 
 
 
 
 
Exercise – GLTEQ 
 
X 
X (except V2) 
X 
X 
School Engagement—mSESQ 
 
X 
X (except V2) 
X 
X 
Academic History—SHQ 
 
X 
 
 
 
Sleep—PSQI 
 
X 
X (except V2) 
X 
X 
Activity Involvement—mYLSBQ 
 
X 
X (except V2) 
X 
X 
Interviews 
 
 
 
 
 
MINI 7.0 Adult, MINI 7.0 Kid 
 
X 
 
 
 
Timeline Follow-Back—TLFB 
 
X 
X 
X 
X 
Cognitive Tests 
 
 
 
 
 
CANTAB 
 
X 
 
X 
X 
Lab Tests 
 
 
 
 
 
Urinalysis 
 
X 
X 
X 
X 
Genetics—Saliva Sample 
 
X 
 
 
 
Estimated Time for Completion (mins) 
10 
120 
10 
60 
60 

13 
 
GWAS Genotyping: The Broad Institute will perform molecular profiling (array-based) of subject samples and 
subsequent in-depth analysis of the data, which will allow us to detect alterations in the genome including point 
mutations, small insertions and deletions, chromosomal copy number alterations, and translocations. These 
experiments are intended to help identify candidate genes involved in the physiopathology of neurological and 
psychological diseases. The molecular information generated from these samples will not be returned to 
subjects at any time.  
 
Data from this study may result in communications in journals or at scientific meetings. Subjects will not be 
identified in those communications. To facilitate research, the genetic information generated may upon 
publication be deposited in protected databases (such as dbGAP) available only to bona fide researchers with 
specific scientific questions who promise to not try to identify individuals. The data will be sent to these banks 
in a coded manner and again will not contain any traditionally used identifier such as name, address, phone 
number, or social security number. Although we cannot predict how genetic information will be used in the 
future, there are many safeguards in place and we do not think that there will be further risks to patients' 
privacy and confidentiality by sharing such information with these banks. 
 
The Broad Institute will not be involved in subject ascertainment. Prior to transfer of bio-specimen aliquots to 
the Broad Institute, samples will be re-encoded at the collaborators institutions. No identifying patient 
information will be shared with Broad scientists at any time. Some limited clinical data will be obtained from 
collaborators. Again, all subject identifying information will remain with the collaborators and only de-identified 
clinical data will be shared with the Broad Institute. 
 
Genetic Data Protection: In addition, steps will be taken to protect confidentiality of genetic data as outlined: 
1) All MGH study staff are trained to make confidentiality the first priority.  
2) No genetic research data will be entered into the medical record. 
3) The results of the genetic analyses will not be shared with participants, their family members or 
unauthorized third parties. 
4) Genetic data are encoded using coded identifiers. These codes, rather than personal identifiers, are 
used in any analytic datasets. The code key linking coded identifiers to personal identifiers are kept in 
an access-restricted, password protected electronic file and are not shared with the genetics 
laboratories.    
5) Consent forms are stored in locked cabinets apart from demographic and diagnostic data.   
6) Samples and genetic data stored in the laboratory will be identified only by the code numbers and 
laboratory personnel will not have access to personal identifiers. 
7) The most serious risk would be identification of individuals in the publicly shared database.  To prevent 
this, computerized data files provided to other investigators will not include any of the HIPPA-defined 
personal identifiers. Published material will not identify subjects.   
 
VI. BIOSTATISTICAL ANALYSES 
This is a first-of-its kind study using a 6-month contingency management paradigm for cannabis abstinence. As 
such, pilot testing needs to occur to evaluate feasibility of this paradigm before a larger trial can be proposed. 
Phase 0 will examine the initial acceptability and feasibility of a contingency management protocol for long-
term abstinence, and collect preliminary data on the efficacy of two competing payment schedules. We will 
calculate continuous abstinence rates at six months. If continuous abstinence rates at six months are low (e.g. 
below 80 percent) and therefore a larger six-month trial is not likely feasible, we will then examine continuous 
abstinence rates at each prior month of the study. This will help us determine the longest trial feasible in this 
population. Phase 1 will collect pilot data on change in cognition with six months of abstinence, using the 
payment schedule informed by Phase 0. These data will be used to estimate effect sizes and inform a 
subsequent power analysis for a fully-powered, randomized trial to be proposed at the completion of this pilot 
study. 
 
VII. RISKS AND DISCOMFORTS 
There are a few potential risks to individuals participating in the study.  
 

14 
 
Psychosocial, Social and Legal risks: There are no uncommon psychological, social, or legal risks 
associated with participation in this study. There is a slight risk that the questionnaires and interviews may 
contribute to temporary discomfort when participants are asked about sensitive behaviors or personal feelings 
(e.g., cannabis use, smoking or mood), but in our experience with similar studies this risk is very minimal. To 
minimize these risks, all data will be coded with unique subject identifiers to help minimize concerns of 
confidentiality which may decrease discomfort to respond to questions and interviews truthfully. Additionally, 
participants will be reminded by MGH study staff that they may omit any questions they do not wish to answer 
or discontinue their participation at any time.  Participants will be told by MGH study staff on the 
assent/consent form that if they feel distressed after participating and wish to discuss their concerns further, 
they may withdraw from the study immediately. Research staff will have information on counseling options for 
trusted treaters in the community available to distribute to participants who request such information. Given 
that we will be meeting with participants regularly and will be administering validated mood and substance use 
questionnaires during each visit, we are also uniquely positioned to monitor changes in endorsement of mental 
health symptoms. For example, we will administer the Concise Health Risk Tracking (CHRT) scale at every 
visit and a consult with a doctoral level clinical will occur for any participant who endorses passive suicidal 
ideation (at a level of “Agree” of above) or active suicidal thoughts (at a level of “Neutral” or above). For any 
participant for whom we have concerns about emotional wellbeing, we will ask him/her if we can discuss this 
with his/her parents/guardians to help coordinate a plan for monitoring and treatment. Finally, on the unlikely 
event that a participant is emotionally distressed, MGH study staff is prepared to deal with such a situation 
should it occur. Our team is comprised of several investigators with significant expertise in mental health 
issues and is well prepared to handle emergency situations: our investigators are well-trained in 
psychotherapeutic interventions to help process and mitigate distress and have significant experience 
assessing for and addressing patient safety. Field staff who collect data will be trained by a licensed 
psychiatrist (A. Eden Evins, MD, MPH) and licensed clinical psychologist (Randi Schuster, PhD) on identifying 
and responding to emotional distress in a research participant. The study will be terminated if the clinician or 
the research team determine that their continued participation is unsafe or not in their best interest, e.g., in 
circumstances where there is deterioration in their mental or physical health judged to require a change in 
medication or hospitalization. 
 
Confidentiality and Privacy: Another potential risk to participants is breach of confidentiality but protecting 
the confidentiality and integrity of our research participants is a top priority for this MGH project. MGH’s careful 
consent and data confidentiality procedures should greatly minimize any potential risk to participants’ privacy. 
Only MGH project investigators and authorized study staff will have access to raw data. Once collected, an 
individual’s data will not be released to anyone outside of MGH authorized project staff. Confidentiality is 
further assured by assigning a unique identifier to each participant. There will be a restricted access master list 
of names and other identifying information linked to the identification number. The master list will be kept on a 
password-protected Partners computer file, separate from other data, along with other materials that have 
participant’s name (e.g., consent forms). No identifying information is listed on participant or parent/guardian 
questionnaires or any other materials with data on them (e.g., cognitive tests, drug tests), with the exception of 
participant initials at the end of questionnaires to indicate that participants completed them directly. Participants 
will complete self-report questionnaires directly on REDCap using a Partners-encrypted device, which greatly 
minimizes the likelihood of confidentiality breaches. Only authorized MGH project members will be allowed 
access to this computer. Any raw data files in electronic format will be housed on our network server at the 
Center for Addiction Medicine at MGH and will be password protected so that only authorized project 
personnel have access to them. These files will not have participant names or identifying information attached 
to them and no information will appear in hospital medical records. Given that this pilot study is only recruiting 
adolescent cannabis users, it is possible that parents/guardians will become aware of their child’s cannabis 
use history by signing the consent form. However, potential participants will be made aware of this during the 
telephone screening and have the option to decline parent/guardian contact, and therefore decline enrolling in 
the study. Additionally, both participants and parents/guardians will be made aware that no details disclosed 
during the study, including those relevant to use history, will be shared with the parents/guardians unless there 
is an immediate concern for safety. 
 

15 
 
In the consent/assent forms, both parents/guardians and participants are informed that only in emergency 
situations (in which an individual is at immediate risk for harm) would we release any information. Specifically, 
if a participant tells us that he/she has intent and/or a plan to cause harm to self or other, we will tell the 
parents/guardians and call 911. If a participant discusses details about ongoing child abuse, we will report such 
abuse to the Department of Child and Families directly. If we learn about mood concerns or problematic 
substance use, we will provide the participant with local and trusted resources for follow-up consultation and 
we will ask him/her if this information can be disclosed to his/her parents/guardians to help coordinate and 
facilitate care. Finally, when the results are published or discussed in conferences, no information will be 
included that would reveal an individual participant’s identity. All data will be analyzed on a group-level and not 
by individual participants. 
 
We believe that staff training is one of the most important ways we can protect our participants from potential 
risks. Staff will participate in intensive training which will be led by Drs. Evins (licensed psychiatrist) and 
Schuster (licensed clinical psychologist) before data collection begins with readings, lectures, role-playing, and 
group discussions. Staff members who collect data will meet with senior investigators on a weekly basis during 
assessment points to discuss any issues, review procedures, and conduct ongoing training on these important 
issues.  
 
A Certificate of Confidentiality from the National Institutes of Health has been obtained for this study. We can 
use this Certificate to legally refuse to disclose information that may identify participants in any federal, state, 
or local civil, criminal, administrative, legislative, or other proceedings, for example, if there is a court 
subpoena. We will use the Certificate to resist any demands for information that would identify participants, 
except in the instances of child abuse and neglect, or harm to self or others.  
 
A. Special Considerations for Participants Recruited from Schools: Parents and staff members at 
participating schools will not be provided any information regarding study participants, including 
cannabis use habits, unless there is deemed risk to self or others. In the consent/assent forms, both 
parents and students are informed that only in emergency situations (in which an individual is at 
immediate risk for harm) would we release any information. Specifically, if a participant tells us that 
he/she has intent and/or a plan to cause harm to self or other, we will tell the parents and call 911. If the 
participant says that he/she has recurrent thoughts about harming him/herself or someone else but 
does not have intent or a plan to do so, we will notify the parents and other appropriate medical or 
counseling personnel. Finally, if a participant discusses details about ongoing child abuse, we will 
report such abuse to the Department of Child and Families directly. If we learn about mood concerns or 
problematic substance use, we will provide the participant with local and trusted resources for follow-up 
consultation and we will ask him/her if this information can be disclosed to his/her parents to help 
coordinate and facilitate care. Additionally, schools that serve as research sites will not be identified 
and only minimal information about their characteristics will be released. Finally, when the results are 
published or discussed in conferences, no information will be included that would reveal an individual 
student’s identity or the name of the school at which the research was conducted. All data will be 
analyzed on a group-level and not by individual participants. 
  
 
VIII. POTENTIAL BENEFITS 
We believe that this research study will help engage participants in meaningful and important research with 
immediate potential benefits to both the individual student and the larger community, will provide for unique 
opportunities for education and outreach, and will yield valuable information that will allow schools to develop 
and integrate prevention programs that are custom-fit to their community needs.  
 
Participants may find that talking about cannabis use increases their awareness of any issues related to drug 
use. Additionally, this project may help several adolescents stop using cannabis even though they may not be 
seeking treatment. At the end of the six-month abstinence trial, we can connect participants to treatment 
resources if desired by the participant, which will help promote longer-term abstinence. Finally, our experience 
with adolescents participating in similar research is that they often enjoy the opportunity to interact with field 

16 
 
staff, to engage in an interesting self-study, and to feel as if they are contributing to research on the lives of 
teenagers.  
 
Information developed from this study may help researchers in the future, and will directly inform the 
development of a fully-powered trial. There is much to be learned from the project including: determining 
understanding of the feasibility and efficacy of a long-term abstinence protocol, as well as of the impact of 
cannabis on cognitive functioning among adolescents, which represents a large and critical gap in the extant 
literature. This pilot study, therefore, is critically needed to determine whether a larger and more 
comprehensive study with a six-month contingency management intervention could be feasibly conducted. 
This larger project, informed by the current pilot study, will directly test whether six months of cannabis 
abstinence is associated with meaningful improvements in cognition, mood, and academic functioning. 
 
The greatest benefit will be to future cohorts of adolescents who will benefit from what is learned from this 
research project. Knowledge from this pilot study and the subsequent fully-powered trial will likely directly 
inform development of prevention and cessation programs that are engaging and effective for adolescents. 
 
IX. MONITORING QUALITY AND ASSURANCE 
All participants will have direct contact information for the principal investigator if they have questions at any 
time. Dr. Schuster is responsible for the overall management of the study and will maintain regular 
communication with all the study staff. The principal investigator will meet weekly with all study investigators to 
review the details of data acquisition and analysis as well as any minor problems. In the event of any minor or 
significant adverse event, the principal investigator will be contacted immediately. The principal investigator is 
responsible for the generation of summary reports documenting this process and outcomes which will be 
included in the Continuing Review reports to the IRB.  
 
Serious adverse events are not expected because of study procedures. Should one occur, it will be reported by 
telephone or email by the principal investigator to the Partners IRB per current PHRC Adverse Event Reporting 
Policy. All adverse events (if not serious) will be reported in writing to the Partners Human Research 
Committee. All information regarding experimental subjects will be kept in the offices of the principal or co-
investigators. All data will be identified by a unique code number.  
 
X. PARTICIPANT COMPENSATION 
All participants will be paid by reloadable cards for their participation and abstinence. Reloadable cards will 
be managed by CT (Clinical Trials) Payer.  CT Payer is a secure web-based platform that facilitates 
“HIPAA & HITECH safe” clinical trial and study-related payments onto prepaid reloadable MasterCards. 
Unlike payment systems offered by banks and third-party payment providers, CT Payer does not collect 
any protected health information from research participants. CT Payer has been approved as a payment 
method by research management and has been used successfully for the past 3 years by a similar protocol 
in our laboratory (PI Dr. Schuster, Protocol #: 2015P000076). 
Phase 0: Participants will be reimbursed using one of two different payment schedules, both escalating based 
on continuous cannabis abstinence (indexed by self-reported non-use and progressively decreasing 
quantitative levels of urine THCCOOH). Compensation for attendance to the baseline visit (Visit 1) will be 
distributed at the end of the study visit, and all compensation for abstinence will be distributed between study 
visits upon receipt of laboratory results from Dominion Diagnostics. Participants are reset to the starting level if 
abstinence is not demonstrated within the first week of study participation. If a participant fails to demonstrate 
abstinence at any point between Week 1 (Visit 3) through the last visit, they will be discontinued from the study 
based on non-compliance with study protocol.  
 
The schedule of reimbursement for session attendance and abstinence (see payment schedule below) was 
informed by the payment schedule utilized by our current one-month abstinence protocol (Protocol #: 
2015P000076). In our one-month abstinence protocol, the schedule of reimbursement is what has been found 
effective in similar populations.34-38 All participants will be paid 10 dollars for attending the Baseline visit (Visit 
1). After the initial baseline visit, the “Low” payment group will receive payments escalating 2 dollars for each 
subsequent visit with verified abstinence (e.g., $12, $14, $16). The “High” payment group will receive 

17 
 
escalating payments of 3 dollars for continuous abstinence following the baseline payment (e.g., $13, $16, 
$19). The schedules of reimbursement for session attendance and abstinence for the current six-month study -
- $910 or $1,235 – are more conservative than the amount of reimbursement estimated should payment from 
our one-month abstinence protocol be extended to six months. That is, the current protocol proposes to 
compensate more than $4,300-4,600 less than that estimated should the compensation schedule from 
Protocol #2015P000076 be extended to six months.  
 
The total amount of reimbursement is thought to be appropriate in this population for the following reasons: 1) 
parents/guardians will be aware of the amount of money that participants can potentially earn by participating 
in the study; 2) all participants will be incentivized to abstain from a health-compromising behavior, that is 
continued use of cannabis; 3) CT Payer greatly minimizes risk of funds being used for illegal purchases.  
 
The table below details the maximum potential earnings; however, the total amount earned will depend on the 
number of sessions attended, and also for evidenced cannabis abstinence. 

18 
 
 
Phase 0 Schedule of Compensation 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Participants may also receive reimbursement for transportation to our center in Boston. They may receive 
$2.00 per ride on the bus or $2.90 per ride on the subway. Payment will be provided on the CT Payer 
reloadable card on the day of the study visit. If a parent accompanies their child to the study visit, they may be 
Month 
Visit Number 
Schedule 
Low 
High 
 
 
0 
Screening 
$0 
$0 
 
1 
Week 0 (V1) 
$10 
(attendance) 
$10 
(attendance) 
 
2 
Week 0 (V2) 
$12 
$13 
1 
3 
Week 1 (V3) 
$14 
$16 
 
4 
Week 2 
$16 
$19 
 
5 
Week 3 
$18 
$22 
 
6 
Week 4 
$20 
$25 
 
 
 
 
 
  
7 
Week 5 
$22 
$28 
 
8 
Week 6 
$24 
$31 
2 
9 
Week 7 
$26 
$34 
 
10 
Week 8 
$28 
$37 
 
 
 
 
 
3 
11 
Week 9 
$30 
$40 
12 
Week 10 
$32 
$43 
13 
Week 11 
$34 
$46 
14 
Week 12 
$36 
$49 
 
 
 
 
4 
15 
Week 13 
$38 
$52 
16 
Week 14 
$40 
$55 
17 
Week 15 
$42 
$58 
18 
Week 16 
$44 
$61 
 
 
 
 
5 
19 
Week 17 
$46 
$64 
20 
Week 18 
$48 
$67 
21 
Week 19 
$50 
$70 
22 
Week 20 
$52 
$73 
 
 
 
 
6  
23 
Week 21 
$54 
$76 
24 
Week 22 
$56 
$79 
25 
Week 23 
$58 
$82 
26 
Week 24 
$60 
$85 
 
 
 
 
 
 
Totals 
$910 
$1235 

19 
 
reimbursed for transportation at the same rate. Parking vouchers are also available for participants or their 
parents who drive to our center and park in an MGH parking garage.   
The payment schedule for Phase 1 will be informed by data collected during the Phase 0 pilot period. This 
protocol will be amended upon completion of Phase 0 to designate the payment schedule to be employed. 
 
 
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