Clinical trial NCT03518567
Conditions: Marijuana Smoking
Sponsor: Brown University
Start date: 2018-10-15; Completion date: 2021-05-24
Enrollment: 133 participants; Allocation: NA; Intervention model: SINGLE_GROUP

Brief summary:
This laboratory study will employ a multi-session experimental design to examine the behavioral economic demand for marijuana, by studying effect of marijuana administration (High THC) on demand for marijuana, and marijuana smoking topography. The study will recruit 100 non-treatment seeking marijuana users who smoke marijuana at least twice weekly.

Detailed description:
This laboratory study will employ a multi-session experimental design to examine craving for marijuana, the effect of marijuana administration (High THC) on behavioral economic demand for marijuana, and marijuana smoking topography. The study will recruit 100 non-treatment seeking marijuana users who smoke marijuana at least twice weekly. The relationship between hypothetical and actual demand for marijuana will be examined. We will also investigate relationship between demand for marijuana and indices of marijuana smoking topography. The study will recruit 100 non-treatment seeking marijuana users who smoke marijuana at least twice weekly to obtain a final sample of 85 with complete data (15% of attrition). Participants will be tested at a baseline session and during two experimental sessions (an ad libitum marijuana smoking session and a marijuana smoking topography session). This study will confirm the utility of the hypothetical marijuana purchase task as a reliable and valid tool for assessing behavioral economic marijuana demand.

Arms: arm 1: Smoked marijuana cigarettes (High THC dose \[6% THC\])
Interventions: intervention 1: Smoked marijuana cigarettes: High THC dose (6% THC)
Intervention descriptions: intervention 1: Smoked marijuana cigarettes (High THC dose \[6% THC\])

Protocol documents:
Prot_SAP_001.pdf: 
 
1
Cover page 
Official Title of study: Behavioral Economic Analysis of Demand for Marijuana 
ClinicalTrials.gov Identifier: NCT03518567 
Document Type: Protocol and Statistical Analysis Plan dated 10/8/2020 
Subtitle: N/A 
(The informed consent form document(s) uploaded in Portable Document Format Archival (PDF/A) format. It 
is strongly encouraged that the PDF/A file also be consistent with the PDF Universal Accessibility (PDF/UA) 
format, to optimize accessibility). 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


 
2
RESEARCH PROTOCOL 
 
Principal Investigator: 
 
Elizabeth R. Aston, Ph.D. 
 
 
 
 
 
 
Brown University School of Public Health 
 
 
 
 
 
 
Center for Alcohol and Addiction Studies 
 
 
 
 
 
 
121 South Main Street, 5th Floor, Providence, RI 02912 
 
 
 
 
 
 
 
Primary Mentor/Co-Investigator: Jane Metrik, Ph.D., Brown University  
 
Project Title:  
 
 
Behavioral Economic Analysis of Demand for Marijuana 
NIDA Grant #: 
 
 
K01DA039311 
Authority: 
 
 
 
This study has been approved by the Brown University Institutional  
Review Board  
 
 
 
 
 
 
 
 
 
 
____________ 
 
 
 
 
 
 
A. RATIONALE AND OVERVIEW 
Since 1996, 20 states (including Rhode Island) and Washington DC have legalized use of marijuana for medical 
purposes, and Washington and Colorado legalized recreational use of marijuana in 2012 [1]. If these trends in 
marijuana legislation continue, the production, advertisement, and sale of marijuana are likely to commence 
across the United States. The relative ease of accessibility to inexpensive marijuana is a considerable risk factor 
for heavy use, as is the case with alcohol [2], and marijuana legalization may amplify initiation and progression 
of use [3]. Due to the shift in normative perceptions surrounding marijuana use [4], an approach to analyze the 
value of this drug is essential. It is not only imperative, but time-sensitive, that we investigate the factors that 
may influence the behavioral economic demand for marijuana in this novel drug market. The goal of the present 
study is to develop and validate a refined measure for assessment of demand for marijuana to be used in future 
investigations.  
 
B.1. SPECIFIC AIMS 
The following aims will remedy prior purchase task limitations and will ultimately address important gaps in 
the drug demand literature: 
 
Aim 1: Validate the Marijuana Purchase Task (MPT) measure via administration to a representative sample of 
marijuana users and assessment of smoking behavior in the laboratory (n=85). Hypothetical MPT responses 
(e.g., how many hits of marijuana would you take if they cost $0.25?, $0.50?, etc…) will be compared to 
responses on an Actual MPT whereby one of the subject’s response choices is selected at random to determine 
the amount of marijuana to be administered. Marijuana smoking topography will be assessed during a 
subsequent ad libitum smoking session. 
Aim 1.1: Test the hypothesis that performance on the Hypothetical MPT will be significantly associated 
with performance on the Actual MPT.  
Aim 1.2: Test hypothesis that marijuana craving post-administration will be lower than craving assessed 
pre-administration.  
Aim 1.3: Test the hypothesis that marijuana puff topography from the ad libitum marijuana self-
administration session will be related to self-reported grams of cannabis used per week. 
 
B.2. SAMPLE DESCRIPTION AND RECRUITMENT 
Participants will be recruited from the community via flyers, advertisements, and social media. Potential 
subjects will be screened via phone and staff will summarize study procedures. Eligible subjects will be 
scheduled for an initial laboratory visit. Preliminary data suggests that there is much variability in marijuana use 
practices; therefore, we will include individuals with a range of use practices and patterns to capitalize on 
variability. During the initial laboratory visit, participants will provide informed consent and will be enrolled in 
the study using the following inclusion criteria:  
 


 
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Aim 1: a) marijuana use at least 4 times in the past month on average and at least monthly for the past 6 months; 
b) English-speaking; c) negative urine toxicology screen for drugs other than marijuana; d) no self-report of 
other illicit drug use in the past 30 days; e) non-treatment seeking; f) purchase of marijuana at least twice in the 
past 6 months to confirm familiarity with the construct to be measured; g) negative pregnancy test; h) not 
nursing; i) use of contraception during the study; j) good physical health; k) zero breath alcohol concentration; 
l) absence of diagnosis of current depression, mania, psychosis, and panic disorder; m) no self-report of past 
serious adverse reaction to marijuana; n) no current psychotropic drug use; o) smoking 0-20 tobacco cigarettes 
per day; p) ability to abstain from marijuana for 15 hours; and q) body mass index in 18.5-30 kg/m2 range. In 
addition, participants must be 18 to 50 years of age. This age range was chosen based on previous marijuana 
self-administration work [5], [6] to minimize potential cardiovascular risk from smoking marijuana, which 
increases with age. Participants who test positive for drugs other than marijuana will be given one re-try 
appointment.  
 
B.3. METHODOLOGY 
Aim 1 Approach. Laboratory Sessions: one experimental session (Session 1: controlled paced puff smoking 
procedure). Participants (n=85) will complete a baseline session with medical screening and two experimental 
sessions (Session 1: controlled paced puffing smoking procedure; Session 2: ad libitum smoking topography). 
Following phone screening, subjects will visit the laboratory to provide informed consent. They will be asked to 
refrain from all marijuana and tobacco smoking for 15 hours, alcohol for 24 hours, and caffeine for 4 hours 
prior to experimental sessions. Subjects will complete an alcohol breathanalysis, a urine drug screen and 
pregnancy test (females), and a carbon-monoxide (CO) reading to confirm absence of recent smoking. Subjects 
with a positive BrAC will be rescheduled. A positive THC screen will be required at this time to confirm 
marijuana status; however, positive results for other drugs will result in ineligibility. Participants who test 
positive for drugs other than marijuana will be given one re-try appointment. Participants that do not test 
positive for marijuana will not be given a re-try appointment. Those with a CO of > 8 ppm will be rescheduled 
due to the difficulty in confirming overnight marijuana abstinence with higher CO levels [7]–[9]. For those with 
a CO reading of more than 8ppm during the baseline session, research staff will consult with the PI on a case-
by-case basis. PI discretion will be used to ensure the target CO reading of 8ppm is obtained. With respect to 
the experimental sessions, for those with a CO reading of more than 8ppm at session arrival, PI discretion will 
be used to ensure the target CO reading of 8ppm will be reached by the onset of marijuana administration. 
Participants will be allowed one re-test in the event of a CO level above the 8 ppm cut-off when the PI has 
determined the participant cannot feasibly reach a CO reading of 8ppm in a timely manner on the same date. 
Tobacco smokers will be allowed to smoke a cigarette following the CO test to prevent nicotine withdrawal. 
Similar CO-based procedures have been used in marijuana administration studies to avoid the onset of cannabis 
withdrawal [9]. Subjects will be administered a medical screening questionnaire to rule out history of adverse 
reaction to marijuana, and a structured clinical interview to rule out Axis I DSM-5 diagnoses. Ineligible subjects 
will be paid $10 and excluded from further participation. Eligible subjects will complete baseline measures and 
undergo a medical screening exam to determine medical clearance prior to the marijuana administration 
sessions.  
 
Drug: Marijuana (5.9% Δ⁹-tetrahydrocannabinol/THC) cigarettes will be provided by the NIDA Drug Supply 
Program. This dose was selected because administration of 5.9% THC will closely model potency of marijuana 
obtained outside the laboratory as marijuana preparations have increased from 3.4% in 1993 to 8.8% in 2008 
[10].  
 
Laboratory Session 1: Controlled Paced Puff Smoking Procedure: Subjects will complete the Hypothetical 
(not associated with marijuana available to smoke) Marijuana Purchase Task (MPT), Actual MPT (identical to 
Hypothetical MPT but a response choice will be selected at random to determine amount of marijuana available 
to be smoked), and self-report measures of craving and subjective effects. A blood pressure cuff will be 
attached to continuously record heart rate (HR) and blood pressure (BP) during the entire experimental session 
for safety monitoring. Selection of marijuana amount available to smoke: A response choice corresponding to 
an item price will be randomly selected from the Actual MPT measure completed during the session. Subjects 


 
4
will draw a number and will be given a monetary budget based on the maximum price set on the MPT measure 
($20) for the marijuana smoking session. Once the response choice/price has been selected, the corresponding 
number of marijuana hits will be available to smoke, and the subject will receive any remaining money from the 
monetary budget (e.g., budget=$20, item selected from Actual MPT =$5/unit, subject reported he/she would 
purchase 3 units at this price, 3 units will be available during the smoking procedure, and subject will receive 
the remaining $5 from the monetary budget). The controlled paced-puffing procedure [11] includes instructions 
to “light the cigarette” (30s), “get ready” (5s), “inhale” (5s), “hold smoke in lungs” (10s), and “exhale.” The 
puffing sequence will continue until the subject chooses to cease smoking or the number of available units has 
been reached (i.e., 20 hits). Subjects are not required to smoke any marijuana as our intention is to assess the 
relationship between Actual MPT performance and real smoking in the laboratory. Subjects will be informed 
that the administration session will last 1-hour regardless of number of marijuana hits available. This 
methodology is based on established procedures that have been successfully used to assess demand for 
Hypothetical versus Actual alcohol [12]. No more than 20 hits total will be available during the session due to 
potential safety concerns (e.g., increases in HR which reliably occur [5], [13]). 
 
Laboratory Session 2. Ad Libitum Smoking Topography Procedure: Participants will complete baseline 
measures including the Hypothetical MPT, and will then complete a 1-hour ad libitum marijuana self-
administration session for assessment of smoking topography. Marijuana cigarettes (5.9% THC) will be smoked 
through a handheld smoking topography device (CReSSMicro™). The device will include a holder for the 
cigarette and study staff will place the cigarette in the device. The subject will light the cigarette and each puff 
will register immediately upon inhalation. Data from the device will be downloaded and indices of topography 
will be recorded including number of cigarettes, number of puffs, puff volume (ml), puff duration (ms), average 
puff velocity (ml/s), and time to peak velocity (ms). Logs will also be maintained by the PI and RA 
documenting number of puffs smoked and each cigarette or partial cigarette smoked ensuring an accurate count 
of marijuana cigarettes smoked during the session. These procedures have been successfully used to assess 
marijuana smoking topography [14]. A maximum of two joints will be available during the session. 
 
Sobriety Assessment: Subjects will receive snacks upon the completion of the administration session. Subjects 
will remain in the laboratory for 3-hours following the smoking procedure (psychotropic effects of smoked 
marijuana taper off within 2-3 hours [15]), and will subsequently be evaluated for motor signs of intoxication. 
Following completion of a field sobriety test [16], subjects will be transported home in a taxi.  
 
Compensation: Participants will be paid $20 for the baseline session, $10 for the physical exam, and $50 for 
each experimental session (and amount remaining from $20 tab) for a total of at least $130 and up to $150.  
 
Security and Regulatory Aspects for Marijuana: Marijuana cigarettes will be provided by NIDA and will be 
stored frozen in an airtight container in a locked refrigerator safe located in a cement block room without 
windows and one door that is locked with code-protected card-key access at 121 South Main Street on the 3rd 
floor. Only DEA designated individuals will have access to this room (located in the same building and floor as 
the location of marijuana administration). Thus, the cigarettes will remain secure at all times. Dr. Aston will 
retrieve a designated number of marijuana cigarettes prior to a scheduled experimental session, humidify them 
at room temperature for 24 hours before use (per NIDA’s instructions) in the same cement block room, and 
transfer them directly to the laboratory following the start of the session.  
 
Statistical Analysis Plan: The primary aim of this investigation is to confirm the validity of the Marijuana 
Purchase Task (MPT; primary outcome measure). A linear regression will be performed with marijuana hits 
purchased on the Actual MPT predicting marijuana hits actually purchased and smoked in the laboratory; 
baseline total individual income will be included as a covariate. The first secondary aim includes change in 
marijuana craving pre- and post-marijuana smoking during the experimental session (secondary outcome 
measure). A two-sided t-test will be conducted to compare craving pre- and post-marijuana smoking. The 
second secondary aim includes correlation between puffs on the topography device during ad libitum marijuana 
administration and self-reported grams of marijuana used per week (secondary outcome measure). 


 
5
References  
 
[1] Office of National Drug Control Policy, “Marijuana Resource Center: State Laws Related to Marijuana | 
The White House.” Accessed: Oct. 29, 2013. [Online]. Available: http://www.whitehouse.gov/ondcp/state-
laws-related-to-marijuana 
[2] J. G. Murphy and J. MacKillop, “Relative reinforcing efficacy of alcohol among college student drinkers,” 
Exp. Clin. Psychopharmacol., vol. 14, no. 2, pp. 219–227, May 2006, doi: 10.1037/1064-1297.14.2.219. 
[3] J. J. Palamar, D. C. Ompad, and E. Petkova, “Correlates of intentions to use cannabis among US high 
school seniors in the case of cannabis legalization,” Int. J. Drug Policy, Feb. 2014, doi: 
10.1016/j.drugpo.2014.01.017. 
[4] Center for Substance Abuse Research, “2013 Gallup Poll Finds Majority of U.S. Residents Think 
Marijuana Use Should Be Legalized,” University of Maryland, College Park, Vol. 22, Issue 43, Oct. 2013. 
Accessed: Nov. 21, 2013. [Online]. Available: http://www.cesar.umd.edu/cesar/cesarfax.asp 
[5] Z. D. Cooper and M. Haney, “Investigation of sex-dependent effects of cannabis in daily cannabis 
smokers,” Drug Alcohol Depend., Jan. 2014, doi: 10.1016/j.drugalcdep.2013.12.013. 
[6] M. Haney, Z. D. Cooper, G. Bedi, S. K. Vosburg, S. D. Comer, and R. W. Foltin, “Nabilone decreases 
marijuana withdrawal and a laboratory measure of marijuana relapse,” Neuropsychopharmacol. Off. Publ. 
Am. Coll. Neuropsychopharmacol., vol. 38, no. 8, pp. 1557–1565, Jul. 2013, doi: 10.1038/npp.2013.54. 
[7] J. Metrik et al., “Effectiveness of a marijuana expectancy manipulation: Piloting the balanced-placebo 
design for marijuana,” Exp. Clin. Psychopharmacol., vol. 17, no. 4, pp. 217–225, Aug. 2009, doi: 
10.1037/a0016502. 
[8] J. Metrik et al., “Balanced placebo design with marijuana: pharmacological and expectancy effects on 
impulsivity and risk taking,” Psychopharmacology (Berl.), vol. 223, no. 4, pp. 489–499, Oct. 2012, doi: 
10.1007/s00213-012-2740-y. 
[9] Z. D. Cooper and M. Haney, “Comparison of subjective, pharmacokinetic, and physiological effects of 
marijuana smoked as joints and blunts,” Drug Alcohol Depend., vol. 103, no. 3, pp. 107–113, Aug. 2009, 
doi: 10.1016/j.drugalcdep.2009.01.023. 
[10] Z. Mehmedic et al., “Potency trends of Δ9-THC and other cannabinoids in confiscated cannabis 
preparations from 1993 to 2008,” J. Forensic Sci., vol. 55, no. 5, pp. 1209–1217, Sep. 2010, doi: 
10.1111/j.1556-4029.2010.01441.x. 
[11] R. W. Foltin, M. W. Fischman, J. J. Pedroso, and G. D. Pearlson, “Marijuana and cocaine interactions in 
humans: cardiovascular consequences,” Pharmacol. Biochem. Behav., vol. 28, no. 4, pp. 459–464, Dec. 
1987, doi: 10.1016/0091-3057(87)90506-5. 
[12] M. Amlung, J. Acker, M. K. Stojek, J. G. Murphy, and J. MacKillop, “Is talk ‘cheap’? An initial 
investigation of the equivalence of alcohol purchase task performance for hypothetical and actual 
rewards,” Alcohol. Clin. Exp. Res., vol. 36, no. 4, pp. 716–724, Apr. 2012, doi: 10.1111/j.1530-
0277.2011.01656.x. 
[13] R. W. Foltin and M. W. Fischman, “The effects of combinations of intranasal cocaine, smoked marijuana, 
and task performance on heart rate and blood pressure,” Pharmacol. Biochem. Behav., vol. 36, no. 2, pp. 
311–315, Jun. 1990. 
[14] E. A. McClure, M. L. Stitzer, and R. Vandrey, “Characterizing smoking topography of cannabis in heavy 
users,” Psychopharmacology (Berl.), vol. 220, no. 2, pp. 309–318, Mar. 2012, doi: 10.1007/s00213-011-
2480-4. 
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42, no. 4, pp. 327–360, 2003, doi: 10.2165/00003088-200342040-00003. 
[16] C. L. Hart, W. van Gorp, M. Haney, R. W. Foltin, and M. W. Fischman, “Effects of acute smoked 
marijuana on complex cognitive performance,” Neuropsychopharmacol. Off. Publ. Am. Coll. 
Neuropsychopharmacol., vol. 25, no. 5, pp. 757–765, Nov. 2001, doi: 10.1016/S0893-133X(01)00273-1. 
  

ICF_000.pdf: 
Cover page 
Official Title of study: Behavioral Economic Analysis of Demand for Marijuana 
ClinicalTrials.gov Identifier: NCT03518567 
Document Type: Informed Consent form dated 10/8/2020 
Subtitle: N/A 
(The informed consent form document(s) uploaded in Portable Document Format 
Archival (PDF/A) format. It is strongly encouraged that the PDF/A file also be 
consistent with the PDF Universal Accessibility (PDF/UA) format, to optimize 
accessibility). 
 


Study 2 Consent 
  
 
Name of Participant 
 
Brown University 
 
Consent Form 
 
Agreement to Participate in a Research Project 
 
BEHAVIORAL ECONOMIC ANALYSIS OF DEMAND FOR MARIJUANA: 
 
KEY INFORMATION: 
You are invited to take part in a Brown University and Lifespan/Rhode Island Hospital research study. 
Your participation is voluntary. 
 
• 
PURPOSE: The study is investigating the effects of marijuana on behavior. How much an individual might pay 
for marijuana may be related to how they react to it and how valuable they perceive marijuana to be. 
 
• 
PROCEDURES: You will be asked to complete various questionnaires and interviews regarding your 
substance use, medical and psychiatric history and mood. You will be asked to refrain from all marijuana 
and tobacco smoking for 15 hours, alcohol for 24 hours, and caffeine for 4 hours prior to sessions. You 
will be asked to breathe into a tube to measure carbon monoxide levels in your lungs and also to measure 
blood alcohol concentration. You will be asked to complete a urine test for drug use and, if you are able to 
become pregnant, for possible pregnancy. At the baseline session, you will be asked to complete the 
questionnaires and also have a physical examination to ensure your safety in the study. For the following 
session, you will be asked to fill out more questionnaires and you will have the opportunity to purchase 
“hits” of marijuana to be smoked in the given duration of time. You will also be asked to complete a brief 
computerized eye-tracking task three times during the session.  
 
• 
TIME INVOLVED: The study will take about 2 hours for the baseline session, and 4-5 hours for 
the experimental session. 
 
• 
COMPENSATION: You may receive up to $100 in Amazon gift cards for your participation in the study. 
 
• 
RISKS: Some of the questionnaires pertain to sensitive information, which can make individuals 
uncomfortable. Therefore, you are free to refrain from answering any of the questions that make you 
uncomfortable. We also ask that you refrain from smoking for at least 15 hours prior to participation in 
the study, which may lead to uncomfortable symptoms associated with avoiding tobacco smoking. After 
smoking marijuana, your judgment may be impaired, so we ask that you stay for a few hours to avoid 
possible adverse events. 
• 
BENEFITS: You will receive no direct benefit from this study. However, this research will help further our 
understanding of marijuana value and behavioral effects of marijuana use. 
 
Principal Investigator 
Elizabeth Aston, Ph.D., Center for Alcohol and Addiction Studies, Brown University School of Public Health, 
Box G-S121-5, Providence, RI 02903. 
 
The Project. 
The purpose of this Brown University research is to investigate the effects of marijuana on behavior. Demand 
for marijuana (how much an individual will pay for marijuana) may be related to how people react to marijuana 
and how valuable they perceive marijuana to be. In this study, we are interested in learning whether demand for 
marijuana is related to behavior and reaction to marijuana’s acute effects. The findings from this study may 
help increase our knowledge about marijuana’s effects. 


What Will Be Done. 
 
In order to confirm your eligibility for the study and complete today’s session, you will be asked to 
complete several brief questionnaires and interviews about your substance use, medical and psychiatric 
history, and mood. You will be asked to breathe into a tube that will measure the amount of carbon 
monoxide in your lungs and this information will be used to confirm that you have avoided all smoking 
prior to today’s session. If the test suggests you have smoked within the past 15 hours, you will not be 
able to complete the session and will be given one more opportunity to come in for a session without 
smoking. You will be asked to blow into a machine that will tell us whether you drank any alcohol 
before coming in. If there is alcohol in your breath, we will have to re-schedule the interview. You will 
also be asked to give a urine sample, which will be tested for recent drug use, and must be positive for 
marijuana. If you are a woman, the urine will also be tested for pregnancy. In the event of a positive 
urine test for illicit drugs other than marijuana, you may reschedule the session once. If you are found to 
be ineligible for the study based on the interview or a repeated positive urine drug test, you will be paid 
$10 for your time and effort. 
 
During today’s session, you will complete paper-and-pencil questionnaires. If you are eligible to 
participate in the study based on the interview and a urine drug test, you will be asked to undergo a 
standard physical and a review of your medical history to determine if it is safe for you to be in the 
study. If it is determined that it would not be safe for you to be in the study, your participation will end. 
If we ask you to complete the physical exam, you will be paid $30 in Amazon gift card at its 
completion ($20 for completion of the baseline session and $10 for completion of the physical exam). 
If you are eligible to participate in the study based on the physical exam, you will be asked to schedule 
one additional session. The next session should be completed from five days to three weeks from the 
previous session. If you are unable to complete them within this time frame, you will be withdrawn 
from the study. 
 
For the next session, you will be asked to refrain from all smoking starting at least 15 hours before your 
sessions, avoid drinking alcohol for 24 hours and any caffeinated beverages for one hour prior to the 
sessions. Just as with the first session, you will be asked to breathe into a tube that will measure the 
amount of carbon monoxide in your lungs, and this information will be used to confirm that you have 
avoided smoking. If the test suggests you have smoked within the past 15 hours, you will not be able to 
complete the sessions and will be given one more opportunity to come in for these sessions without 
smoking. You will also be asked to blow into a machine that will tell us whether you drank any alcohol 
before coming in that day. If there is alcohol in your breath, you will not be eligible to continue. You 
will be asked to give another urine sample, which will be tested for recent drug use. If you are a woman, 
the urine will also be tested for pregnancy. 
 
At the next session, you will be asked to fill out some brief questionnaires and a computerized eye 
tracking task. Then, you will be asked to smoke a marijuana cigarette. The cigarettes will be provided 
by the National Institute of Drug Abuse. During this session, you will have the opportunity to purchase 
“hits” of marijuana with a monetary tab we will provide to you. We will monitor your blood pressure 
and heart rate while you are smoking. Following the end of the marijuana administration portion of the 
session, you will be asked to complete the same computerized eye tracking task as you did prior to 
smoking. Afterwards, you will receive snacks and you will be asked to complete the eye tracking task 
again one hour later. For your safety, we ask that you remain in the laboratory for 3 hours after the end 
of the smoking portion of the study to allow for the effects of marijuana to dissipate. After 3 hours, you 
will be evaluated for signs of marijuana intoxication and you will complete a field sobriety test. 


Following successful completion of the sobriety test, you will be permitted to leave. You may not drive 
yourself or operate any other form of transportation (e.g., a bike, scooter, skateboard, etc.) but you may 
use other forms of transportation to get home (e.g., designated driver, taxi, bus, walk, etc.). 
 
Today’s session will last about two hours and the next session will last 4-5 hours. In Amazon gift cards, 
you will earn $20 for completing the baseline session, $10 for completing the physical exam, and $50 
for completing the smoking session, plus the amount that you can earn during the experimental session 
(up to $20). The total possible payment you may earn for participating in this study will be $100 in 
Amazon gift card, and the minimum you will earn for completing both days is $80. To ensure valid 
data, it is important that you complete all of the study-related activities according to the specified 
procedures.  
 
You are free to stop the study at any point during the session. If you choose to stop participating 
before the second session is complete, you will receive a partial payment of $10 for that session. 
 
Benefits. 
 
You will receive no direct benefit from the research procedures. However, data obtained from this 
research may further our understanding regarding marijuana value and behavioral effects of marijuana 
use. 
 
Potential Risks and Protections Against Risk. 
 
Some of the questions ask about personal matters, including thoughts and feelings which may be 
private, and about behaviors including drug use. For example, questions like, “How many hours are 
you high or under the influence of cannabis on a typical day?” will be asked. These questions may 
make you uncomfortable. Therefore, you are free not to answer any questions you do not wish to 
answer. In addition, you will be asked to avoid all smoking for a period of at least 15 hours. Avoiding 
tobacco smoking can cause some uncomfortable symptoms such as irritability, anxiety, difficulty 
concentrating, and craving for cigarettes. You will have the option to smoke a tobacco cigarette in the 
beginning of each of the study sessions after your carbon monoxide levels are tested upon arrival. 
You will be asked to smoke marijuana, which may contain tar and other cannabinoids and result in 
carbon monoxide increases, and is also classified as a controlled substance. Carbon monoxide 
exposure will be equivalent to one marijuana cigarette and may exceed that of a tobacco cigarette. 
After smoking marijuana, your judgment may be impaired for a few hours, which is why you will 
need to stay with us during that time. A possible adverse effect of active marijuana is an acute anxiety 
reaction. We will monitor your reactions to marijuana at all times during the smoking session. If you 
experience any anxiety, you will be immediately evaluated by the study’s Principal Investigator, Dr. 
Elizabeth Aston. Dr. Jane Metrik, a study Co-Investigator, is a licensed clinical psychologist and will 
be readily available in case of any psychological adverse reaction to the drug. Another possible 
adverse event is short-term dry mouth, which should be mild. If you need water, we will provide it for 
you. Another possible adverse effect of active marijuana is a short-term increase in heart rate. We will 
monitor your heart rate, blood pressure, and your reactions to marijuana at all times during the 
experimental session. If you experience any heart rate increases that are more severe or longer-lasting 
than you have experienced previously with marijuana, or if you are experiencing chest tightening or 
chest pain, please let us know and we will ensure that the appropriate emergency medical treatment is 
provided. You are also free to stop smoking at any point during the smoking session. 
 


Due to potential adverse effects of alcohol or marijuana on a fetus, it is important for female 
participants to use a reliable means of contraception if engaging in sexual intercourse with a man 
during the course of this study. If you are capable of becoming pregnant and want to participate in this 
study, you must agree to complete a pregnancy test that we will provide and to use a medically 
accepted means of birth control. Let us know if you change your mind and decide to become pregnant 
during the study. You must not nurse a baby while participating in this study. 
 
The computerized eye tracking task is noninvasive. This task involves watching a brief video move 
around the perimeter of an LCD monitor positioned in front of you while a camera records your eye 
positions. As such, it is very unlikely to cause any discomfort. Further, the risk of breach of 
confidentiality associated with this technology is very low.  
 
Confidentiality. 
 
All data and other information related to you will be kept confidential. Given the sensitive nature of this 
research, we will implement multiple procedures to protect your identity. We will not put your name on 
any data forms; only this consent form and telephone/email contact form will have your identifying 
information on them. Your consent form and telephone/email contact information will be stored in a 
locked location separate from all the questionnaires and data. Your telephone/email contact form will be 
shredded after you complete the study unless you indicate that you are willing to be contacted for future 
research studies. All assessment data will be coded with an identification number rather than using your 
name and will be stored in locked file cabinets and password-protected computer files available to the 
investigators and our research team only. The cross-index of your name and participation ID number 
will be kept in a separate locked location. The cross- 
index will be destroyed after your study completion. The computer forms we use for the 
questionnaires will facilitate confidentiality by separating questions from answers. 
 
Brown University and Lifespan/Rhode Island Hospital staff sometimes review studies like this one 
to make sure they are being done safely and correctly. If a review of this study takes place, your 
records may be examined. The reviewers will protect your confidentiality. 
 
This research study is a clinical trial. A description of this clinical trial will be available on 
https://www.clinicaltrials.gov, as required by U.S. Law. This website will not include information that 
can identify you. At most, the website will include a summary of the results. You can search this 
website at any time. To help us protect your privacy, we have obtained a Certificate of Confidentiality 
from the National Institutes of Health. The researchers can use this Certificate to legally refuse to 
disclose information that may identify you in any federal, state, or local civil, criminal, administrative, 
legislative, or other proceedings, for example, if there is a court subpoena. The researchers will use the 
Certificate to resist any demands for information that would identify you. The Certificate cannot be 
used to resist a demand for information from personnel of the United States Government that is used 
for auditing or evaluation of Federally funded projects or for information that must be disclosed in 
order to meet the requirements of the federal Food and Drug Administration (FDA). You should 
understand that a Certificate of Confidentiality does not prevent you or a member of your family from 
voluntarily releasing information about yourself or your involvement in this research. If an insurer, 
medical care provider, or other person obtains your written consent to receive research information, 
then the researchers will not use the Certificate to withhold that information. The Certificate of 


Confidentiality will not be used to prevent disclosure to state or local authorities of child abuse or intent 
to hurt self or others. 
 
Right to Quit the Research at Any Time. 
 
Participation in this study is strictly voluntary. If you decide to participate, you will be free to withdraw 
from the research program at any time and it will not affect your relationship with Brown University or 
Lifespan/Rhode Island Hospital. If you choose not to participate in this research, but would like 
information on marijuana treatment programs, we will provide you with a list of potential resources. 
 
Who to Call. 
 
Please ask any questions you may have now. If at any time you have further questions about this project 
or your rights as a participant, please feel free to ask the Principal Investigator, Dr. Elizabeth Aston, at 
(401) 863-6668. Please call Dr. Aston and study staff at (401) 863- 6668 if any potentially adverse 
events occur in between study visits. If you have any questions about your rights as a participant, you 
may also contact the Brown University Human Research Protection Program at (401) 863-3050. 
 
Consent to Participate. 
 
(Check Yes or No, and sign your initials) 
 
I agree to be re-contacted for future studies: 
 Yes 
 No 
(initials) 
 
 
Your signature below means that you have read the information on this form, asked any questions you 
have about the project, and agree to participate in this study as indicated above. You will be given a 
copy of this form to keep. 
 
 
I agree to participate in this project. 
Signature of participant 
Date 
Signature of witness (Research Staff) 
Date 
Copies to: 
 
Participant; Investigator’s files 
(Version 9, date 10/8/2020)