Typical Hits, Grams, or Joints: Evaluating Cannabis Survey Measurement Strategies for Quantifying Consumption

Cannabis Use and Academic Performance in College Students: The Role of Procrastination

Objective

The current study investigated procrastination as a potential moderator of the association between cannabis use and college grade point average (GPA). Participants: 220 college students (ages 18 - 24; 71.8% female) in the Northwestern U.S. who were registered for classes in Fall 2021.

Methods

Demographic questions, substance use history, the Beck Anxiety Inventory, the Center for Epidemiologic Studies Depression scale, and a Procrastination scale were completed via an online survey. Official term and cumulative GPA records were also collected.

Results

A regression model indicated that procrastination moderated the association between lifetime cannabis use and cumulative college GPA, whereas this moderation was not present when examining the relationship between past month cannabis use and term GPA.

Conclusion

The current study identifies a putatively modifiable factor that may be related to academic performance for students who use cannabis. These results may help inform future interventions designed to help students using cannabis succeed academically.

Estimating THC Consumption from Smoked and Vaped Cannabis Products in an Online Survey of Adults Who Use Cannabis

Introduction: Quantification of consumption patterns of the primary psychoactive compounds in cannabis, which cause euphoria or intoxication, is sorely needed to identify potential risks and benefits of use and to provide meaningful safety information to the public. The diversity of products available, multiple methods of administration, and lack of labeling of products have made such quantification challenging. Our group is developing a survey instrument for estimating the quantity of delta 9-tetrahydrocannabinol (THC) consumed in population samples, which is flexible and incorporates individualized reports of patterns of consumption. This study provides an illustration of a procedure for translating self-reported consumption into milligrams of THC (mgTHC), which may serve as a working model for future quantification efforts. Methods: Social media advertising was leveraged to enroll 5627 adults who use cannabis into an online, anonymous survey study. Only those who used cannabis in the past 7 days, used flower or concentrate products, and who chose to report their quantity of use in hits per day or grams per week (n=3211) were included in this report. Formulas were used to estimate mgTHC used per day, in hits per day or grams per week; potency (%THC); constants for estimating the amount of material consumed for each hit; and a method of administration efficiency constant to account for THC loss due to the administration method. Results: The estimate for mgTHC used per day was M=92.8 mg/day (SD=97.2 mg; 1st-3rd quartile range=25-132 mg). The estimated quantity of use was much lower for those reporting in hits (M=43.7 mg, SD=43.8) than for those reporting in grams (M=115.1 mg, SD=107.0). The estimated rate of binge use in the past week, arbitrarily defined as more than 50 mgTHC within any one daily time quadrant, was 6.8%, which increased to 29.3% if 25 mgTHC was used. Conclusions: The approach illustrated in this study goes beyond existing cannabis measures by asking participants to provide highly detailed estimates of their past 7-day use patterns and then applying a logical formula to translate this information into mgTHC. This initial procedure has limitations and lacks generalization; however, we hope this demonstration stimulates testing of similar approaches and relevant laboratory experiments that will enhance the validity of cannabis consumption estimation procedures.

How much cannabis is used in a joint in Australia? An experimental investigation into use by potency and frequency

INTRODUCTION

Cannabis use is highly prevalent in Australia, yet current survey metrics measure tetrahydrocannabinol (THC) exposure with limited accuracy. Often survey items measure cannabis quantity by assuming specific modes of use (i.e., 'how many joints do you use?'), which fail to capture variations in cannabis use and the diverse modes of use (e.g., joints, cones, spliffs). This study investigated how much cannabis is used in these modes of administration in an Australian sample.

METHODS

Participants (N = 31, Mage  = 25.77; 51% university students) completed the Roll a Joint Paradigm in which they rolled joints, spliffs and packed cones as they would typically, using oregano as 'cannabis.' Participants then prepared each again but with cannabis of higher or lower potency.

RESULTS

The amount of cannabis used across different modes of administration was variable: joints (range 0.10-1.25 g), spliffs (range 0.12-1.21 g) and cones (range 0.03-0.41 g). Participants who used cannabis daily rolled three times the amount of cannabis into a joint.

DISCUSSION AND CONCLUSIONS

The amount of cannabis used in common modes of administration may be highly variable. Daily use may be associated using larger quantities of cannabis. Titration attempts based on potency were not proportional or consistent across modes of administration. The results indicate people may adjust the quantity of cannabis based on perceived potency, however, not proportional to THC concentration. Inconsistency in the amount of cannabis used based on potency and within different modes of administration may represent a problem for self-report metrics which ask participants to report cannabis use in joints.

Exploring survey methods for measuring consumption quantities of cannabis flower and concentrate products

Background: Researchers need accurate measurements of cannabis consumption quantities to assess risks and benefits. Survey methods for measuring cannabis flower and concentrate quantities remain underdeveloped.Objective: We examined "grams" and "hits" units for measuring flower and concentrate quantities, and calculating milligrams of THC (mgTHC).Methods: Online survey participants (n = 2,381) reported preferred unit (hits or grams), past-week hits and grams for each product, and product %THC. Quantile regression compared mgTHC between unit-preference subgroups. Hits-based mgTHC calculations assumed a universal grams-per-hit ratio (GPHR). To examine individualized GPHRs, we tested a "two-item approach," which divided total grams by total hits, and "one-item approach," which divided 0.5 grams by responses to the question: "How many total hits would it take you to finish 1/2 g of your [product] by [administration method]?"Results: Participants were primarily daily consumers (77%), 50% female sex, mean age 39.0 (SD 16.4), 85% White, 49% employed full-time. Compared to those who preferred the hits unit, those who preferred the grams unit reported consuming more hits and grams, higher %THC products, and consequently, larger median mgTHC (flower-hits mgTHC: 32 vs. 91 (95%CI: 52-67); flower-grams mgTHC: 27 vs. 113 (95%CI: 73-95); concentrate-hits mgTHC: 29 vs. 59 (95%CI: 15-43); concentrate-grams mgTHC: 61 vs. 129 (95%CI: 43-94)). "Two-item" and "one-item" approach GPHRs were similar and frequently 50% larger or smaller than the universal GPHR.Conclusion: Allowing respondents to choose "hits" or "grams" when reporting cannabis quantities does not compromise mgTHC estimates. A low-burden, one-item approach yields individualized "hit sizes" that may improve mgTHC estimates.

Self-report methodology for quantifying standardized cannabis consumption in milligrams delta-9-tetrahydrocannabinol

Background: There is currently no format-independent method to determine delta-9-tetrahydrocannabinol (THC) in milligrams for self-report studies.Objectives: Validate self-report method for quantifying mg THC from commercially available cannabis products using product labeling, which includes both net weight and product potency.Methods: 53 adult cannabis users (24 M, 29F), 21-39 years of age (M = 28.38, SD = 4.15), were instructed to report daily use via a weekly survey for two consecutive weeks, provide product label photographs, abstain from use for 24 h, submit a urine sample and complete the Cannabis Use Disorder Identification Test - Revised (CUDIT-R) and the Marijuana Craving Questionnaire - Short Form (MCQ-SF). Milligrams of THC were determined by multiplying quantity of product used by its THC concentration. Urine was analyzed for the urine metabolite 11-nor-carboxy-THC (THC-COOH) via liquid chromatography mass spectroscopy. THC and THC-COOH values were log10 transformed prior to correlational analyses.Results: Median daily THC consumption was 102.53 mg (M = 203.68, SD = 268.13). Thirty-three (62%) of the 53 participants reported using two or more formats over the 2-week period. There was a significant positive correlation between log10 THC-COOH and log10 THC mg (r(41) = .59, p < .001), log10 THC mg and MCQ-SF score (r(41) = .59, p < .001), and log10 THC mg dose and CUDIT-R score, (r(41) = .39, p = .010).Conclusion: Our label-based methodology provides consumption information across all modalities of cannabis use in standard units that can be combined across products for calculation of dose. It is a viable and valid method for quantifying mg of THC consumed and can be utilized in any region where cannabis is legal, and labeling is regulated.

Extending Gender- and Sex-Based Analyses in Cannabis Research: Findings from an Online Sample of Gender Diverse Young Adult Consumers

Background: Gender and sex can influence cannabis behaviors and consequences (Cannabis Use Disorder [CUD]). Research typically examines sex and gender independently. Gender analyses often exclude transgender and gender diverse (TGD) populations. The objectives of this study were to (a) replicate less frequent cannabis use among TGD young adults compared to cisgender counterparts (b) compare severity of CUD, and (c) examine the role of sex on cannabis outcomes. Method: Online survey participants between 18 and 34 (N=1213) from the United States who reported past-week cannabis consumption provided information on cannabis practices and CUD from February to April 2022. Bivariate analyses explored gender differences across frequency (daily frequency across routes of administration [ROAs]; daily use of 2+ ROAs, use throughout the day) and CUD. Adjusted regression models provided model-estimated marginal probabilities and means to examine differences across four gender-by-sex categories (cisgender men: n=385; cisgender women: n=681; male-at-birth TGD: n=26; female-at-birth TGD: n=121). Benjamini-Hochberg adjustments (10% false discovery rate) were applied. Results: Among past-week consumers, female-at-birth TGD participants demonstrated lower probability of daily flower smoking compared to cisgender men (0.54 vs. 0.67). Cisgender men reported greater probability of daily concentrate vaping (0.55) compared to cisgender women (0.45) and female-at-birth TGD participants (0.27); they were also more likely to report daily use of 2+ ROAs (cisgender men: 0.51 vs. cisgender women: 0.39 and female at-birth TGD: 0.27). TGD participants reported greater CUD severity compared to cisgender counterparts, t(1096)=-3.69, p=0.002. Model-estimated means found lower severity among cisgender women compared to cisgender men and female-at-birth TGD participants. Stratified regression models support positive associations between daily cannabis use and CUD in both TGD in cisgender groups. Among cisgender participants, greater severity was predicted by male sex, younger age, and younger age of onset. Conclusions: The present study replicates and extends a prior finding that among past-week cannabis consumers, TGD young adults report less frequent use than cisgender counterparts. Despite this, TGD participants demonstrated greater severity of CUD. While analyses were limited by the small sample of male-at-birth TGD participants, the article highlights the importance of expanding sex- and gender-focused analyses. Future work is expanding efforts to target hard-to-reach consumers.

Evaluating cannabis exposure in survey items: Insights, strategies, and remaining challenges identified from cognitive interviewing

Background

The diversity in characteristics of cannabis products and behavior patterns make evaluation of cannabis exposure in population-based, self-report surveys challenging. Accurate identification of cannabis exposure and related outcomes necessitates a thorough understanding of participants' interpretations of survey questions assessing cannabis consumption behaviors.

Objectives

The current study utilized cognitive interviewing to gain insight on participants' interpretation of items in a self-reported survey instrument used to estimate the quantity of THC consumed in population samples.

Methods

Cognitive interviewing was used to evaluate survey items assessing cannabis use frequency, routes of administration, quantity, potency, and perceived "typical patterns" of use. Ten participants ≥18 years (n = 4 cisgender-men; n = 3 cisgender-women; n = 3 non-binary/transgender) who had used cannabis plant material or concentrates in the past week were recruited to take a self-administered questionnaire and subsequently answer a series of scripted probes regarding survey items.

Results

While most items presented no issues with comprehension, participants identified several areas of ambiguity in question or response item wording or in visual cues included in the survey. Generally, participants with irregular use patterns (i.e., non-daily use) reported more difficulty recalling the time or quantity of cannabis use. Findings resulted in several changes to the updated survey, including updated reference images and new quantity/frequency of use items specific to the route of administration.

Conclusion

Incorporating cognitive interviewing into cannabis measurement development among a sample of knowledgeable cannabis consumers led to improvements in assessing cannabis exposure in population surveys, which may otherwise have been missed.