Addiction, Author Interviews, Cannabis / 25.03.2020

MedicalResearch.com Interview with: Ryan J. McLaughlin, PhD Assistant Professor Department of Integrative Physiology & Neuroscience College of Veterinary Medicine Washington State University, Pullman, WA Ryan J. McLaughlin, PhD Assistant Professor Department of Integrative Physiology & Neuroscience College of Veterinary Medicine Washington State University, Pullman, WA MedicalResearch.com: What is the background for this study? Response: The evolving legal landscape concerning the use of cannabis has increased urgency to better understand its effects on the brain and behavior. Animal models are advantageous in this respect; however, researchers traditionally use forced injections of synthetic cannabinoids which fails to capture the complex effects of volitional cannabis consumption. In our study, we developed a novel model of cannabis self-administration using response-contingent delivery of vaporized cannabis extracts containing high concentrations of Δ9 tetrahydrocannabinol (THC) or cannabidiol (CBD). (more…)
Annals Internal Medicine, Author Interviews, Cannabis, Yale / 19.03.2020

MedicalResearch.com Interview with: Joshua D. Wallach, MS, PhD Assistant Professor of Epidemiology (Environmental Health Sciences) Yale School of Public Health New Haven, CT MedicalResearch.com: What is the background for this study? Response: Over the past few years, there has been growing interest in the potential health benefits of cannabidiol (CBD), a chemical compound in cannabis. Although only one CBD-derived prescription drug has been approved by the US Food and Drug Administration (FDA) for the treatment of epilepsy, I recently started seeing products containing CBD advertised and sold across the US (e.g. CBD in foods, beverages, dietary supplements, and cosmetics). I noticed that many of these products were being marketed with unproven claims to prevent, cure, and treat various conditions, and became interested in learning more about the research supporting the use of CBD, the potential for misleading claims, and impact that the CBD-industry may be having on research that is being generated and disseminated to the public. Research funding sources and other author conflicts of interests (e.g. consulting fees, honoraria, travel expenses) can influence the way that research is designed, conducted, and reported. Previous studies have consistently demonstrated associations between authors' conflicts of interest and proindustry conclusions in clinical research. Given the growing number of companies invested in CBD's commercial success, we decided to analyze the disclosed funding sources, conflicts of interest statements, author employment details, and CBD-related conclusions in a large sample of published articles on the characteristics, use, and therapeutic effects of cannabidiol. (more…)
Aging, Author Interviews, Cannabis, Geriatrics, JAMA, NYU / 24.02.2020

MedicalResearch.com Interview with: Benjamin H. Han, MD MPH Assistant Professor Division of Geriatric Medicine and Palliative Care New York University School of Medicine MedicalResearch.com: What is the background for this study? Response: In the past, the prevalence of cannabis use (both for recreational and for medicinal purposes) was very low among adults age 65 and older. As a reference, the national prevalence rate of past-year cannabis use among adults age 65 and older in 2006-2007 was 0.4%, it has increased dramatically since then. (more…)
Author Interviews, Cannabis, Columbia, Heart Disease, JACC / 21.01.2020

MedicalResearch.com Interview with: Ersilia DeFilippis, MD Second-year cardiology fellow Columbia University Irving Medical Center and NewYork-Presbyterian MedicalResearch.com: What is the background for this study? Response: Marijuana use has been increasing significantly and is the most commonly illicit drug used in the United States. In recent years, more states have been legalizing its use for both recreational and medicinal purposes. We have all seen news reports regarding the rise of vaping-related health hazards. Yet, data are limited regarding the cardiovascular effects of marijuana which is what drove us to explore this topic. (more…)
Author Interviews, Cannabis, JAMA, Pediatrics / 20.12.2019

MedicalResearch.com Interview with: Hongying (Daisy) Dai, PhD Associate Professor Department of Biostatistics | College of Public Health University of Nebraska Medical Center  MedicalResearch.com: What is the background for this study? Response: E-cigarette use increased significantly from 2017 to 2019 among U.S. adolescents, and marijuana and other substances besides can be used in e-cigarettes. Meanwhile, restrictions on marijuana use have been relaxing and social acceptability of marijuana use is shifting among youth. This study analyzed 38,061 middle and high school students from the 2017 and 2018 National Youth Tobacco Survey.  (more…)
Accidents & Violence, Author Interviews, Cannabis / 05.12.2019

MedicalResearch.com Interview with: Nathan J. Connealy Doctoral student John Jay College of Criminal Justice CUNY MedicalResearch.com: What is the background for this study? Response: The background, or what prompted this study, is that research on this topic is pertinent right now as more states continue down a path towards legalization. A large share of the research base and public debate centers around the potential adverse effects of marijuana accessibility, consumer-based concerns, and health specific outcomes associated with usage. This research instead focuses on a lesser explored question related to the potential for the physical dispensary locations to impact crime levels, which is also an important consideration when assessing the impact of recreational marijuana legalization. (more…)
Author Interviews, Brigham & Women's - Harvard, Cannabis, JAMA, Pediatrics / 26.11.2019

MedicalResearch.com Interview with: Bertha K. Madras PhD Director, Laboratory of Addiction Neurobiology Psychobiologist, Substance Use Disorders Division, Basic Neuroscience Division Professor of Psychobiology, Department of Psychiatry Harvard Medical School MedicalResearch.com: What is the background for this study? Parent use of marijuana is rising, and I wondered whether this could be associated with offspring use of specific substances and across several substances
  • Several fathers have confided in me that they used marijuana to bond with their sons. They became horrified after witnessing their sons progress to using other drugs, especially heroin.
  • In general, living with a parent using substances or having substance use disorders is an explicit risk for use of substances among young offspring. Yet, few studies have directly examined whether parental marijuana use elevates the risk for opioid misuse among adolescent and young adults living with parents.  Most importantly and to the best of our knowledge, none of the existing research  simultaneously explored frequency of  parental marijuana use and whether it related to adolescent and young adult offspring’s marijuana, tobacco, alcohol use, and opioid misuse.
(more…)
Author Interviews, Cannabis, Heart Disease, Stroke / 17.11.2019

MedicalResearch.com Interview with: Rupak Desai, MBBS Research Fellow, Division of Cardiology Atlanta VA Medical Center MedicalResearch.com: What is the background for this study? Response: Amidst legalization of therapeutic and recreational use of marijuana/cannabis in the United States, cerebrovascular effects of marijuana use remain largely unknown, especially among young adults. We examined the association between cannabis use (18–44 years) among young adults and stroke events. The study analyzed pooled data from the Behavioral Risk Factor Surveillance System (2016–2017)—a nationally representative cross-sectional survey collected by the Centers for Disease Control and Prevention. Overall, 13.6% of total 43,860 young adults (18-44 years) reported using cannabis recently (in the last month), with 63.3% of them being men. Compared with nonusers, marijuana users were often younger, non-Hispanic white or black, and with some college education. (more…)
Author Interviews, Cannabis, JAMA, UCSD / 23.10.2019

MedicalResearch.com Interview with: John W. Ayers, PhD, MA Vice Chief of Innovation | Assoc. Professor Div. Infectious Disease & Global Public Health University of California San Diego MedicalResearch.com: What is the background for this study? Response: Touted as a “cure all,” researchers have documented unfounded claims that  cannabidiol (CBD) treats acne, anxiety, opioid addiction, pain, and menstrual problems. You can buy CBD droplets, massage oils, CBD gummies, or even ice cream. But public health leaders have been mostly silent on the subject because they lacked data that demonstrates just how popular CBD is and the future trajectory might be. To fill this data-gap we analyzed Google search queries that mentioned “CBD” or “cannabidiol” emerging from the United States from January 2004 through April 2019 and forecasted searches through December 2019. Rather than relying on self reports, where some might not be willing to discuss CBD openly, our strategy allowed us to directly observed millions of instances of people seeking out information or even shopping for CBD online. (more…)
Accidents & Violence, Author Interviews, Cannabis / 14.10.2019

MedicalResearch.com Interview with: “Smoking Marijuana” by Martin Alonso is licensed under CC BY 2.0Ruibin Lu Assistant Professor of Criminal Justice Stockton University Absecon, New Jersey MedicalResearch.com: What is the background for this study? Response: We are witnessing a trend of legalizing marijuana in the United States and in the world. Many states have either legalized recreational marijuana or are considering it. At the same time, there are concerns about what will happen to our society if weed is legal. One of the concerns is about crime rates: are we going to experience more or fewer crimes after legalizing recreational marijuana? This is a legitimate question that we should consider when making cannabis-related public policies. Our research provides a preliminary answer to this question. It analyzes crime rates before and after the legalization using rigorous scientific methods and provides more information on how marijuana legalization may affect crime rates. (more…)
Author Interviews, Cannabis, JAMA / 05.10.2019

MedicalResearch.com Interview with: Hongying (Daisy) Dai, PhD Associate Professor Department of Biostatistics | College of Public Health University of Nebraska Medical Center  MedicalResearch.com: What is the background for this study? Response: Although marijuana is still classified as a Schedule I drug at the Federal level, as of June 2019, 33 states and the District of Columbia have legalized one or more forms of marijuana; 11 states and the District of Columbia have approved both medical and recreational uses. Public opinion on marijuana has changed dramatically over the last two decades and support for legalization has doubled since 2010. However, very little is known about the prevalence and patterns of marijuana use among adults with medical conditions. This study analyzed the 2016 and 2017 Behavioral Risk Factor Surveillance System data to report the prevalence and patterns of marijuana use among adults with self-reported medical conditions.  (more…)
Author Interviews, Cannabis, Columbia, Gender Differences / 06.09.2019

MedicalResearch.com Interview with: Morgan Philbin, PhD MHS Assistant Professor Department of Sociomedical Sciences Columbia University School of Public Health MedicalResearch.com: What is the background for this study? Response: Marijuana is the most frequently used substance in the United States (US) after alcohol and tobacco. In 2017, 15.3% of the US population ages 18 and up reported past-year marijuana use (MU) and 9.9% past month use. Individuals who identify as lesbian, gay, or bisexual (LGB), also report higher levels of marijuana use and marijuana use disorder than their heterosexual counterparts. Researchers have begun to explore potentially modifiable factors, such as state-level marijuana policies, that affect marijuana use and related outcomes at the population-level and within subgroups—though as of yet not among sexual minority populations. We therefore examined whether LGB individuals living in states with medical marijuana laws (MMLs) have higher levels of marijuana use and marijuana use disorder compared to LGB individuals in states without MMLs. (more…)
Author Interviews, Cannabis / 31.08.2019

MedicalResearch.com Interview with: Angela Birnbaum, Ph.D., FAES Professor, Director of Graduate Studies Experimental and Clinical Pharmacology College of Pharmacy University of Minnesota  MedicalResearch.com: What is the background for this study? Response: Little was known about the effect food has on the amount of cannabidiol (CBD) that is actually absorbed into the body. Because of various state laws, CBD preparations vary from state to state. In Minnesota, however, the law only allows pure forms of cannabidiol providing a consistent supply of product including a purified CBD capsule formulation. Due to its pharmacological properties a low amount of a CBD dose reaches the blood stream and the effect of food had not been well described. Our study was done to determine the amount of cannabidiol that is absorbed with food as compared to an empty stomach at doses used in epilepsy patients, which can be higher than the dose often used for other conditions.   (more…)
Addiction, Alcohol, Author Interviews, Cannabis, Cocaine, Methamphetamine, Opiods / 21.08.2019

MedicalResearch.com Interview with: Greg Midgette, PhD Assistant Professor Department of Criminology and Criminal Justice University of Maryland MedicalResearch.com: What is the background for this study? Response: This report estimates marijuana, cocaine, heroin, and methamphetamine use in the U.S. between 2006 and 2016 on three dimensions: the number of past-month chronic users per year, where "chronic" has previously been defined as consuming the drug at least four days in the past month, expenditure per drug among those users, and consumption of each drug. These measures are meant to aid the public and policy makers' understanding of changes in drug use, outcomes, and policies.   (more…)
Author Interviews, Cannabis, Depression, OBGYNE / 08.08.2019

MedicalResearch.com Interview with: Jamie A. Seabrook, Ph.D. Associate Professor, School of Food and Nutritional Sciences Brescia University College at Western University Adjunct Research Professor, Dept of Paediatrics, Western University Adjunct Associate Professor, Dept of Epidemiology & Biostatistics, Western University Scientist, Children's Health Research Institute Scientist, Lawson Health Research Institute MedicalResearch.com: What is the background for this study? What are the main findings? Response: Alcohol, tobacco, and cannabis are the most commonly used substances during pregnancy. High alcohol consumption has been linked with preterm birth, and tobacco and/or cannabis use is associated with low birth weight. Much of what we know about predictors of drug use during pregnancy comes from the United States and Australia, with limited studies in Canada. The objective of our study was therefore to assess the relative effects of socioeconomic, demographic, and mental health risk factors associated with drug use during pregnancy. Our retrospective cohort study consisted of 25,734 pregnant women from Southwestern Ontario. We found that maternal depression was the top risk factor associated with all three substances. Compared to women who were not depressed during their pregnancy, women who were depressed were 2.2 times more likely to use alcohol (95% CI: 1.6, 2.9), 1.7 times more likely to smoke tobacco (95% CI: 1.5, 2.0), and 2.6 times more likely to use cannabis (95% CI: 2.0, 3.4). (more…)
Addiction, Author Interviews, Cannabis, Columbia, JAMA, Opiods / 18.07.2019

MedicalResearch.com Interview with: Silvia S. Martins, MD, PHD Associate Professor of Epidemiology Department of Epidemiology Mailman School Of Public Health Columbia University  MedicalResearch.com: What is the background for this study? Response: Prior studies have suggested t6hat medical marijuana legalization might play a role in decreasing opioid use. We aimed to test this hypothesis using individual level data on nonmedical use of prescription opioids and opioid use disorder  from the US National Survey on Drug Use and Health.  (more…)
Author Interviews, Cannabis, JAMA, Pediatrics / 09.07.2019

MedicalResearch.com Interview with: D. Mark Anderson, Ph.D. Associate Professor Department of Agricultural Economics and Economics Montana State University, IZA, and NBER MedicalResearch.com: What is the background for this study? What are the main findings?  Response: Using data from the Youth Risk Behavior Surveys for the period 1993-2017, we explore the effect medical and recreational marijuana laws have on teen use. We find that medical marijuana laws (MMLs) are not associated with teen marijuana consumption, but recreational marijuana laws (RMLs) are actually negatively associated with teen use.  (more…)
Author Interviews, Cannabis, Pediatrics / 21.06.2019

MedicalResearch.com Interview with: Marilyn Cyr, Ph.D., Psy.D. Postdoctoral Research Scientist Division of Child and Adolescent Psychiatry New York State Psychiatric Institute Columbia University Medical Center New York, NY 10032 MedicalResearch.com: What is the background for this study? Response: A hallmark feature of problematic substance use is compulsive drug-seeking long after the drug is no longer experienced as pleasurable and despite the associated adverse consequences of this behavior. Disturbances in cognitive control—an ensemble of processes by which the mind governs behaviors, regulates impulses and guides decisions based on goals—are believed to be involved in the initiation and maintenance of the compulsive drug-seeking that characterizes problematic substance use. Most adults with problematic substance use began having problems with drugs and alcohol in adolescence, a developmental period during which the neural circuits underlying cognitive control processes continue to mature. As such, the adolescent brain may be particularly vulnerable to the effects of substance use, and particularly cannabis, the most commonly used recreational drug by teenagers worldwide. (more…)
Author Interviews, Cannabis / 03.06.2019

MedicalResearch.com Interview with: Julie Bobitt, PhD Director Interdisciplinary Health Sciences College of Applied Health Sciences University of Illinois at Urbana Champaign Champaign, IL  61820 MedicalResearch.com: What is the background for this study? Response:  Older adults are using cannabis at an increasing rate but little is known about their attitudes about, and experiences – including outcomes- with, recreational and medical cannabis use. We believed a qualitative study, where we conducted focus group interviews, would provide a novel perspective to our understanding and help to identify the most salient themes concerning the use of medical and recreational cannabis by adults aged 60 and older living in Colorado. (more…)
Author Interviews, Cannabis, PLoS / 09.05.2019

MedicalResearch.com Interview with: Kyle Gardiner B.Pharm(Hons)PhD candidateDiscipline of PharmacyQueensland University of Technology | QUT · Brisbane, Australia Kyle Gardiner B.Pharm(Hons) PhD candidate Discipline of Pharmacy Queensland University of Technology | QUT · Brisbane, Australia MedicalResearch.com: What is the background for this study?   Response: The background to this study was a personal interest in behavioural science. I am often intrigued as to why health professional behave the way they do. Studies exploring health professional behaviour are seldom complete or comprehensive, however. Medicinal cannabis presents an interesting case point to explore health professional behaviours due to its topical nature. The socio-political discussion surrounding medicinal cannabis is often quite different from the medical discussion, yet for legal and regulated access to be achieved across most jurisdictions, a health professional is required to be involved in that process. Simply, if health professionals are not willing to behave, the delivery of medicinal cannabis does not occur. For purposes of transparency, I neither support or reject the use of medicinal cannabis and this paper has nothing to do improving or reducing access. This paper is about beginning to understand health professional behaviours within the context of medicinal cannabis. Yet, if we hope to change practice in the future, by definition, we need to change behaviour. We cannot change behaviour without first understanding the behaviour in context. (more…)
Addiction, Author Interviews, Cannabis, Pediatrics, Smoking, Tobacco, Tobacco Research / 30.04.2019

MedicalResearch.com Interview with: Joan S. Tucker, Ph.D. Senior Behavioral Scientist RAND Corporation Santa Monica, CA MedicalResearch.com: What is the background for this study?   Response: In light of young adults’ expanding access to cannabis through legalization for recreational use, there has been growing interest in the co-use of cannabis with tobacco/nicotine products.  Although existing data show that young adults who use cannabis products also tend to use tobacco/nicotine products, little is known about how these products are typically used together. Existing research on co-use has mostly focused on combustible products, not accounting for the recent proliferation in cannabis and tobacco/nicotine product types and methods of use (e.g., vaping). Further, not much is known about whether there are important differences between types of co-use (e.g., using both products on the same occasion, one right after another, but not mixing them vs. using both products by mixing them in the same delivery device) in terms of heaviness of use, consequences from use, or associations with young adult functioning. This study was designed as an important first step toward understanding cannabis and tobacco/nicotine co-use behavior among young adults and addressing these gaps in the research literature. (more…)
Accidents & Violence, Author Interviews, Cannabis / 26.04.2019

MedicalResearch.com Interview with: Angela Eichelberger, Ph.D. Senior Research Scientist Insurance Institute for Highway Safety MedicalResearch.com: What is the background for this study? Response: Dr. Romano and Dr. Kelley-Baker have previously studied the problem of child endangerment in alcohol-related crashes. In the United States, each year, about 200 children die and another 4,000 are injured while being driven by a drinking adult. For this study, we wanted to take the opportunity to look at the prevalence of alcohol and cannabis use among drivers who participated in a roadside survey in Washington State. To our knowledge, this is the first study to examine cannabis use among drivers transporting a child. (more…)
Author Interviews, Cannabis, Psychological Science, Social Issues, Weight Research / 24.04.2019

MedicalResearch.com Interview with: "Chocolate Brownies" by Kurtis Garbutt is licensed under CC BY 2.0. To view a copy of this license, visit: https://creativecommons.org/licenses/by/2.0Jessica S. Kruger PhD Clinical Assistant Professor Department of Community Health and Health Behavior School of Public Health and Health Professions University of Buffalo Daniel J. Kruger PhD Adjunct Faculty Associate, Population Studies Center. Michigan's Population Studies Center  MedicalResearch.com: What is the background for this study? Response: The legal environment for cannabis is changing rapidly and an increasing proportion of people are using cannabis for medical and recreational purposes. All policy and practice should be informed by science, yet there is a large gap between evidence and existing practices, and the current scope of research on cannabis users is limited. Public Health has the responsibility of protecting the public, maximizing benefits and minimizing harm in any area. However, the Public Health approach to cannabis has largely been limited to a focus on abstinence, and Federal regulations have restricted the scope of cannabis-related research. (more…)
Author Interviews, Cancer Research, Cannabis, End of Life Care, NYU / 28.03.2019

MedicalResearch.com Interview with: Arum Kim, MD Assistant Professor Medicine and Rehabilitation Medicine NYU School of Medicine Director of the Supportive Oncology Program Perlmutter Cancer Center MedicalResearch.com: What is the background for this study?   Response: There is increasing interest in medical marijuana and its applications for patients with cancers. Despite increasing access, little is known regarding doses of cannabinoids - specifically delta-8-tetrahydrocannabinol (delta-8-THC)  and cannabidiol (CBD), methods of drug delivery, and differences in patterns of use between cancer and non-cancer patients. (more…)
Author Interviews, Cannabis, JAMA, Mental Health Research, OBGYNE / 28.03.2019

MedicalResearch.com Interview with: Jeremy Fine B.A. in Philosophy, Neuroscience, and Psychology Washington University in St. Louis, Class of 201 MedicalResearch.com: What is the background for this study? What are the main findings? Response: Alongside increasingly permissive marijuana use attitudes and laws, the prevalence of marijuana use among pregnant mothers has increased substantially (by 75% between 2002 and 2016), with some evidence that pregnant women may be using cannabis to combat pregnancy-related nausea. Our data came from the Adolescent Brain Cognitive Development (ABCD) Study, which included over 4,000 subjects with data on maternal marijuana use during pregnancy. Our main finding was that the children of mothers who used marijuana after learning they were pregnant had a small but significant increase in risk for psychosis in their future. (more…)
Accidents & Violence, Author Interviews, Cannabis / 22.02.2019

MedicalResearch.com Interview with: Lonnie M. Schaible PhD Associate Professor School of Public Affairs University of Colorado Denver, CO MedicalResearch.com: What is the background for this study? Response: Following legalization of recreational marijuana use in Colorado, strong -- but unsubstantiated -- claims were being made about crime surrounding marijuana dispensaries.  We wanted to know what the data would show.  We were especially interested in determining whether the addition of recreational facilities had any effects above and beyond those which might exist for medical dispensaries.  To better capture the dynamic landscape of marijuana legalization, this is the first study to control for the prior existence of medical dispensaries and assess how effects of both of these types of establishments changed over time. (more…)
Author Interviews, Cannabis, University of Michigan / 17.01.2019

MedicalResearch.com Interview with: Daniel J. Kruger, PhD Research Assistant Professor University of Michigan MedicalResearch.com: What is the background for this study? Response: We study health-related behaviors, such as diet and the consumption of caffeine and alcohol. Given the recent trends in legalization of cannabis for medical and even recreational purposes, we were concerned with the narrow focus of current public health efforts regarding cannabis. Although some in the field take a harm-reduction approach to substance use, too many efforts focus solely on abstinence. These programs are a legacy from the era of prohibition, and we know that there are disadvantages to such a restricted scope in public health. For example, municipalities that eliminated or blocked accurate and effective sex education had increases in teenage pregnancy rates. There are so many public health-related aspects of cannabis, beyond risks and adverse effects, which need to be addressed by systematic scientific research. Because of the legal history of cannabis, there is little integration with the mainstream health care system. The focus of the current study was investigating how medical cannabis users perceived medical cannabis in comparison to pharmaceutical drugs and other aspects of the mainstream health care system and how they navigated they relationships between these currently separate systems (more…)
Author Interviews, Brigham & Women's - Harvard, Cannabis, JAMA, Mental Health Research, Pediatrics / 19.12.2018

MedicalResearch.com Interview with: Sharon Levy, MD, MPH Director, Adolescent Substance Use and Addiction Program Boston Children's Hospital Associate Professor of Pediatrics Harvard Medical School  MedicalResearch.com: What is the background for this study? What are the main findings? Response: ​For this study we analyzed data that were collected as part of a larger survey study that recruited a sample of adolescents who were coming to the doctor's office for routine medical care.  We asked them a lot of questions about their health, school, extracurricular activities, plans for the future, substance use patterns and problems associated with use among other things. The main finding was that among the participants who reported marijuana use in the past year, many of them, more than 40%, said that they had experienced either an hallucination, or paranoia/anxiety related to their use. Kids who used more frequently and those who met criteria for a substance use disorder were more likely to experience these symptoms, as were those who had symptoms of depression (more…)
Author Interviews, Cannabis, University of Pennsylvania / 02.12.2018

MedicalResearch.com Interview with: Daniel Romer PhD Annenberg Public Policy Center The University of Pennsylvania Philadelphia, PA MedicalResearch.com: What is the background for this study? What are the main findings? Response: Previous research has found some troubling relations between adolescent cannabis use and subsequent increases in conduct problems and other unhealthy consequences.  These studies were done in New Zealand in the late 90’s and we wanted to re-examine those relationships using more contemporary data in the US. We had data on 364 adolescents who were followed from age 13 to 19 in Philadelphia that could provide a more up to date picture of the effects of using cannabis on one important outcome, conduct disorder.  We also wanted to use more sensitive methods than had been used in prior research that would enable us to examine reciprocal relations between cannabis use and c (CP).  That is, it might be the case that youth with CP are prone to using cannabis and that this helps to explain why there appears to be a relation over time between cannabis use and CP rather than cannabis use leading to CP. Our findings supported that hypothesis.  There was no prospective relation between changes in cannabis use and subsequent changes in conduct problems.  Instead, changes in conduct problems were found to predict changes in use of cannabis.  Youth with conduct problems also affiliated more with peers who used cannabis, adding further to their own use.  There was also no evidence that youth who used cannabis sought out peers who used it apart from the effects of CP. Finally, both use of cannabis and  conduct problems predicted subsequent development of a mild cannabis use disorder (CUD).  (more…)