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

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

Aim: Standardized survey measures that capture diverse cannabis consumption patterns are needed to inform public health and policy. Our team is developing a flexible, personalized, low-burden survey item inventory to measure cannabis use patterns and estimate milligrams of THC (mgTHC) consumption in large samples. This study aimed to identify measurement gaps and analysis implications associated with an initial pool of candidate items that assessed use of cannabis flower and concentrate products (smoked and/or vaporized). Methods: Adult cannabis consumers (n=4247) completed an online survey assessing cannabis use frequency, quantity, product types, product potencies (%THC), and methods of administration. Participants chose to report their consumption quantities using one of three units: "hits per day," "grams per week," or "joints per week." Respondents also indicated whether their past 7-day consumption pattern represented their typical pattern. Results: Eighty-one percent had used cannabis daily in the past week. Thirty-two percent, 53%, and 15% chose to report flower and concentrate consumption quantity in hits, grams, and joints, respectively. Approximately 80-90% of responses for the number of hits, grams, and joints consumed were less than the maximum response option-suggesting that response options captured the full range of potential cannabis consumption behaviors. Those who chose grams or joints units were generally more likely to endorse higher risk cannabis use (e.g., morning use, high %THC products) in the past week than those who chose the hits unit (adjusted Odds Ratio range: 1.2-3.9). Among those who reported that the past week represented their typical behavior (83%), past 30-day and past 7-day frequencies were highly correlated (Spearman's Rho=0.77)-supporting the feasibility of using lower burden "typical week" items to extrapolate patterns beyond a 1-week time frame. Conclusion: Results from this online convenience sample of frequent cannabis consumers suggest that the current items yield coherent and expected response patterns. Although additional testing is required, a standardized, flexible survey instrument for large-scale assessment of cannabis patterns and calculation of mgTHC seems within reach.

Evaluating age-related disparities in cannabis-related problems among LGBT+ versus non-LGBT+ adults

LGBT+ adults demonstrate greater cannabis-related problems (e.g., Cannabis Use Disorder [CUD]) compared to non-LGBT+ counterparts. No study has explored age-related disparities in cannabis problems across the adult lifespan, nor have studies identified specific CUD criteria that contribute to elevated CUD among LGBT+ adults. The purpose of this study was to examine associations between LGBT+ identity and age with endorsement of CUD criteria in a sample of regular cannabis consumers. An online sample of N = 4334 (25.1% LGBT+) adults aged 18-64 residing in the U.S. completed an online survey about cannabis use behaviors and CUD diagnostic criteria. Bivariate contrasts revealed significantly greater CUD criteria endorsement among LGBT+ respondents, largely driven by differences at younger ages. However, this effect disappeared in the majority of adjusted logistic regression models. LGBT+ identity was associated with greater probability of use in larger amounts (adjOR = 2.10, 95% CI: 1.22-3.60) and use despite physical/mental health problems (adjOR = 2.51, 95% CI:1.23-5.03). No age*LGBT+ identity interactions were detected. Plotted trends depict more pronounced disparities in outcomes among LGBT+ adults under 35 years. Several potential risk and protective factors including employment, education, and reasons for use were identified. There were age-related differences in these characteristics among LGBT+ and non-LGBT+ respondents. Initial findings highlight the need for LGBT+ research examining trends in health outcomes and sociodemographic and cannabis characteristics across the lifespan. The study also provides a substantive contribution regarding specific cannabis-related problems that young LGBT+ cannabis consumers may be more likely to endorse than their non-LGBT+ counterparts.

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.

Ecological investigation of the co-occurrence of posttraumatic stress disorder symptoms and cannabis use among community women experiencing intimate partner violence

BACKGROUND

Women experiencing intimate partner violence (IPV) are at increased risk for developing hazardous patterns of cannabis use. Research suggests that women experiencing IPV use cannabis to cope with posttraumatic stress disorder (PTSD) symptoms. To advance research, we used experience sampling methods to explicate the within-day concurrent and proximal relations between PTSD symptom clusters and cannabis use among women experiencing IPV.

METHOD

Participants were 145 community women (M age = 40.66, 41.6% white, 31.4% Black, 10.9% Hispanic or Latina, 8% American Indian/Alaska Native, 5.8% Bi-/multi-racial) experiencing IPV and using substances who completed three surveys a day for 30 days.

RESULTS

Externalizing behavior (OR = 1.37, 95% CI [1.15, 1.65], p < 0.001) and dysphoric arousal (OR = 1.27, 95% CI [1.09, 1.49], p = 0.002) PTSD symptom clusters were associated with cannabis use reported in the same survey period. Results from the lagged models found no proximal associations between PTSD symptom clusters and cannabis use.

CONCLUSIONS

Results highlight the acute effects of externalizing behavior and dysphoric arousal PTSD symptoms on cannabis use among women experiencing IPV. These findings may inform prevention and intervention efforts for cannabis use in this population.

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.