Research Article  153 

Ved  

 

 
 

 

 

ABSTRACT 

 
Objective: Estimating delta-9 tetrahydrocannabinol (mgTHC) using hits involves converting hits to grams 

via a grams-per-hit ratio (GPHR). Previous studies assumed a single hit size (SHS), ignoring individual hit 

size variations. This study investigates a multiple qualitative hit size (MQHS) approach based on self-

reported hit sizes (small, medium, large) to improve mgTHC estimates. Method: Adults (N = 1,824) who 

used cannabis in the past week completed an online survey on cannabis consumption, reporting quantities 

in hits and grams, and estimating their hit sizes. We calculated mgTHC using both SHS (0.06g/hit for 

flower, 0.012g/hit for concentrate) and MQHS. For the MQHS approach, we calculated median GPHRs for 

each hit size group and assigned those medians to individuals within that group. Results: For flower, 

median GPHR increased with hit size (small: 0.042, medium: 0.062, large: 0.093). The MQHS estimate for 

mgTHC from flower was higher than SHS for large hits (95% CI:[12.4, 50.0]) but showed no difference for 

medium or small hits (95% CI: [-3.2, 8.1]; 95%CI: [-27.6, 3.4]). For concentrate, median GPHR was similar 

for small and medium hits but lower than large hits (small: 0.024, medium: 0.025, large: 0.035). MQHS 

estimates for mgTHC were higher than SHS for all hit sizes (95% CI: [46.3, 86.3]; 95% CI: [24.8, 45.5]; 95% 

CI: [11.5, 36.5] for large, medium, small hits, respectively). Conclusions: The MQHS estimates captures hit 

size variability for flower. The floor effect with median GPHRs for concentrates suggests further 

investigation is needed for MQHS estimates with concentrates. The MQHS approach illustrates a method 

to develop new standard GPHRs for each qualitative hit size group, after further investigation. 

 

Key words: = THC exposure; cannabis quantification methods; cannabis, estimation; THC dosing 

Cannabis use is gaining popularity in the 

United States, and the diversity of cannabis 

products continues to grow with changing 

cannabis laws (Davenport, 2021; Hall & Lynskey, 

2020; Spindle et al., 2019). Δ9-

tetrahydrocannabinol (THC) is a major 

psychoactive cannabinoid in most cannabis 

products that can cause intoxication and 

behavioral impairment related to the amount 

consumed (Compton et al., 2019; Rajapaksha et 

al., 2020). Similarly, potential therapeutic 

benefits of cannabis products may be related to 

dosing effects. Understanding how much THC 

individuals consume is important to both limit 

adverse effects and maximize potentials benefits 

of cannabis use. Yet, with the vast variety of 

Mohammad I. Habib1, Alan J. Budney1, Cara A. Struble1, Deborah 

S. Hasin2,3,4, Ofir Livne3,4, Efrat Aharonovich2,3, Caroline Wisell4, 

Sara N. Fragione1, Jacob T. Borodovsky1 

1Center for Technology and Behavioral Health, Geisel School of Medicine, Dartmouth College 
2Department of Psychiatry, Columbia University Irving Medical Center 
3New York State Psychiatric Institute 
4Department of Epidemiology, Columbia University Mailman School of Public Health 

 

Cannabis 

2025 

© Author(s) 2025 

researchmj.org 

10.26828/cannabis/2025/000285 

Volume 8, Issue 2 

 

Estimating Cannabis 

Consumption in Milligrams of 

THC From Self-Reported Hit 

Size 

Corresponding Author: Mohammad Habib, B.A., Colorado State University, 410 W Pitkin St. Fort Collins, CO, 

80523. Phone: (970) 491-6197. Email: Mohammad.I.Habib@colostate.edu 



Cannabis, A Publication of the Research Society on Marijuana             

 

154 

products on the market, it is difficult to 

standardize the measurement of THC 

consumption across multiple product types (i.e., 

edibles, flower, concentrates, etc.). 

Accurately estimating THC consumption in 

real-world settings is difficult due to multiple 

factors. Many cannabis products do not have 

adequate labels that indicate milligrams of THC 

(mgTHC) per product/serving. For instance, the 

most commonly used products, cannabis flower 

and concentrate, might not be labeled, and those 

that are may only list the potency (%THC) and 

product weight rather than the total amount of 

mgTHC in the product (Davenport, 2021). 

Translating potency and weight to mgTHG 

consumed requires additional information about 

1) the quantity of product that was consumed (i.e., 

how many grams were loaded in the pipe/joint or 

how many hits/puffs were taken) and 2) the 

method of administration to account for any THC 

that is lost while consuming the product (i.e., side 

smoke, pyrolysis, etc.).  

 

Prior Work Quantifying mgTHC 
 

Our group has been working towards a 

solution to quantify THC consumption across 

multiple routes of administration and product 

types. An initial study on smoked and vaped 

products indicated that consumers showed 

preferences for how they estimated the amount of 

cannabis consumed; 55% vs. 45% selected to 

report in number of grams and hits, respectively 

(Borodovsky et al., 2023). Allowing a choice of how 

to report amounts consumed reduces cognitive 

burden and likely increases accuracy. To estimate 

mgTHC for those reporting in number of grams 

(Formula 1), we multiplied the number of grams 

of product by the potency of product and then 

adjusted for lost THC during the consumption 

process, using the method of administration 

efficiency constant (MAEC; Budney et al., 2022). 

 
𝐹𝑜𝑟𝑚𝑢𝑙𝑎 1 
 

𝑚𝑔𝑇𝐻𝐶 =  𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑔𝑟𝑎𝑚𝑠 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 

∗ 𝑃𝑜𝑡𝑒𝑛𝑐𝑦 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 (%𝑇𝐻𝐶) 
∗ 𝑀𝐴𝐸𝐶 

 

 

 

 

For those reporting in hits, we converted the 

number of hits into the number of grams using a 

grams-per-hit ratio (GPHR) derived from prior lab 

studies (Formula 2). After converting hits to 

grams, we calculated mgTHC by multiplying the 

derived grams value by the potency of product and 

applied the MAEC adjustment. In this hits-to-

grams model, the accuracy or validity of the 

GPHR substantially impacts the precision of the 

mgTHC estimate.   

 
𝐹𝑜𝑟𝑚𝑢𝑙𝑎 2 
  
𝑚𝑔𝑇𝐻𝐶 =  𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 ℎ𝑖𝑡𝑠 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 

∗ 𝐺𝑃𝐻𝑅 

∗ 𝑃𝑜𝑡𝑒𝑛𝑐𝑦 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 (%𝑇𝐻𝐶) 
∗ 𝑀𝐴𝐸𝐶 

 

Grams-per-hit Ratios (GPHR) 
 

No consensus for an appropriate GPHR is 

available. In our initial study and in two other 

published studies, a single GPHR drawn from 

human lab studies was used for all participants 

(Borodovsky et al., 2022; Budney et al., 2022; 

Lynch et al., 2021; McClure et al., 2012; Varlet et 

al., 2016). This single GPHR assumes all 

participants have the same single hit size (SHS). 

An SHS GPHR could potentially provide a 

reasonable estimate among all cannabis 

consumers, as it represents an average value 

across a multitude of cannabis consumers. 

However, prior studies clearly demonstrate that 

consumers inhale hits that vary substantially in 

size and across product types (Heishman et al., 

1989; Matthias et al., 1996; McClure et al., 2012). 

Thus, an SHS GPHR could substantially 

overestimate or underestimate mgTHC 

consumption for many consumers. 

To better estimate individual use, we 

developed two methods to capture individual hit 

size (Borodovsky et al., 2023). The first approach 

required two survey items asking participants to 

report their consumption in both the number of 

hits and grams, regardless of the preferred unit. 

Individual GPHRs were calculated by dividing the 

grams of product consumed per day by the hits of 

product per day. The second approach used one 

survey item asking participants how many hits it 

would take them to finish a half gram of flower or 

concentrate using their preferred method of 

administration. Their individual GPHR was 



Multiple Qualitative Hit Size    
 

155 

calculated by dividing a half gram by the 

estimated number of hits. A within-subject 

comparison of these two approaches found that 

regardless of product type or GPHR approach, 

45% of participants had an individual GPHR that 

was 50% larger or smaller than the SHS GPHR 

used in the initial study. While both individual 

approaches addressed the variability in hit size, 

both also required individuals to think about their 

consumption in number of grams, which can be 

potentially challenging, given that many cannabis 

consumers struggle to accurately estimate small 

quantities of cannabis in grams (Prince et al., 

2018). Such contemplation increases cognitive 

burden and likely decreases the accuracy of 

mgTHC among those who prefer to report their 

use in number of hits.  

 

The Current Study  
 

To further reduce burden without sacrificing 

accuracy, we sought to develop a GPHR approach 

that accounted for multiple qualitative hit sizes 

(MQHS) and allowed those who prefer the hits 

unit to estimate their use by only thinking about 

hits. This MQHS approach requires asking one 

qualitative hit size survey question: “When you 
smoke or vape, do you take a small, medium, or 
large hit?”  The present study illustrates a method 

to generate and establish standard MQHS GPHRs 

for those who report taking small, medium, or 

large hits, and then compares mgTHC estimates 

derived using the MQHS GPHR approach with 

estimates calculated using the SHS GPHRs. If 

standard MQHS GPHRs can be established and 

validated, future studies that require mgTHC 

estimates would only need to include this single 

MQHS item to obtain a GPHR for those who 

prefer to report in hits.  

 

METHODS 

 
Sample Recruitment and Sample Size 
 

This study is part of a larger study detailed 

elsewhere (Borodovsky et al., 2023). Adults 18+ 

were recruited using Facebook and Instagram 

advertising with cannabis related key-word 

targeting (Borodovsky et al., 2018). Those who 

clicked on the advertisement were redirected to the 

survey consent page hosted on Qualtrics 

(Qualtrics, Provo, UT). Participants were recruited 

between June 1 - July 9, 2022. The Dartmouth 

Committee for Protection of Human Subjects 

approved all study procedures. No compensation 

was provided for participation. 

A total of n = 3,658 clicked on the 

advertisement link, of whom 39 were ineligible 

(i.e., 4 were less than 18 years old, 35 were 

potentially bots). Among those who consented and 

were eligible, 812 were excluded due to 

inconsistent responding. Of the remaining n = 

2,807, 447 were excluded for not using flower or 

concentrate products in the past week, and 536 

were excluded for not providing all necessary items 

to calculate milligrams of THC. The final analytic 

sample size was N = 1,824.  

 

Survey Items and Design 
 

The survey consisted of 59 items, designed 

based on prior literature (Borodovsky et al., 2018; 

Cuttler & Spradlin, 2017; Sikorski et al., 2021) and 

included data quality checks, such as reCAPTCHA, 

bot-only items, and attention checks. Additionally, 

the survey queried sociodemographics, past 30- 

and past 7-day frequency, and methods of 

administration (smoking flower, vaping flower, 

vaping concentrate, dabbing concentrate, edibles, 

liquids/tinctures, and capsules).  

All participants reported their past-week 

flower and concentrate consumption both in the 

number of hits and grams of product. To control for 

ordering effects, participants were randomized 

with equal probabilities to either report number of 

hits first (n = 912) or report number of grams first 

(n = 912).  

Consumption quantity. Participants were 

initially asked if they used the same amount of 

product on each day they used for flower and 

concentrates, separately. Those who used the same 

amount were asked to estimate their typical 

number of hits and grams of flower and/or 

concentrate used per time-of-day quadrant 

(morning 6AM – 12PM, afternoon 12PM – 4PM, 

evening 4PM – 8PM, night 8PM – 6AM). Those who 

did not use the same amount were asked for the 

number of hits/grams of flower and concentrate per 

time-of-day quadrant for their most recent day of 

use. Response options for number of hits of both 

flower and concentrate were 0, 1, 2, 3, 4, 5, 6, 7, 8, 

9, 10, 11-15, 16-20, 21-25, 26-30, over 30 hits. For 

calculation of mgTHC, midpoints were used for 

ranges (i.e., if participant selected 16-20 hits, we 



Cannabis, A Publication of the Research Society on Marijuana             

 

156 

used 18 hits in the formula). Response options for 

number of grams of flower and concentrate were: 

1/16, 1/8, 1/4, 1/2, 3/4, 1, 1 1/4, 1 1/2, 1 3/4, 2, Over 

2g. More details can be found elsewhere 

(Borodovsky et al., 2022).  

Potency. Participants reported their product 

potency (%THC) using a sliding scale. The survey 

assessed the potency of flower, prefilled THC 

cartridges, and other concentrates (e.g., oils, wax, 

shatter, etc.). Flower potency ranged from 0% to 

30% THC. Both prefilled THC cartridge and other 

concentrate potency options ranged from 40% to 

100% THC.  

Qualitative hit size. Participants were asked to 

report their estimated hit size for their flower and 

concentrate use. Response options were “Small 

hit,”, “Medium hit,” and “Large hit,” and included 

the following statement in the instructions: “A 
large hit would be the amount of air you inhale to 
hold your breath for as long as possible.” 

 

GPHR Approaches  
 
Single hit size (SHS). GPHRs were derived 

from the average number of grams consumed per 

hit as described in lab-based research studies. The 

final assumptions of the averages being one hit of 

flower results in consumption of 0.06g of the 

product (GPHR for flower = 0.06g), and one hit of 

concentrate results in 0.012g of concentrate 

product being consumed (GPHR for concentrate = 

0.012g (Budney et al., 2022; Lynch et al., 2021; 

McClure et al., 2012; Varlet et al., 2016).   

Multiple qualitative hit sizes (MQHS). GPHRs 

that correspond to small, medium, or large hit sizes 

were determined as follows: each participant’s 

individual GPHR was first calculated by dividing 

the number of grams consumed per day by the 

number of hits taken per day. Median GPHRs were 

then calculated separately for participants that 

reported small, medium, or large hit sizes, 

respectively. Each participant who reported a 

small hit size was assigned the small hit size 

median GPHR, those reporting medium hit size 

were assigned the medium hit size GPHR, and so 

forth. This procedure was followed for both flower 

and concentrate products. 

 

Calculating Milligrams of THC 
 

To calculate milligrams of THC (mgTHC), we 

used Formula 2 described above. Two mgTHC 

estimates were obtained for each participant: one 

using the SHS GPHR (formula 3) and one using the 

MQHS GPHR (formula 4), with the only difference 

being the GPHR constant.  

 
𝐹𝑜𝑟𝑚𝑢𝑙𝑎 3. 

 
 𝑚𝑔𝑇𝐻𝐶 =  𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 ℎ𝑖𝑡𝑠 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 

∗ 𝑆𝐻𝑆 𝐺𝑃𝐻𝑅 

∗ 𝑃𝑜𝑡𝑒𝑛𝑐𝑦 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 (%𝑇𝐻𝐶) 

∗ 𝑀𝐴𝐸𝐶 

 
𝐹𝑜𝑟𝑚𝑢𝑙𝑎 4. 

 
 𝑚𝑔𝑇𝐻𝐶 =  𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 ℎ𝑖𝑡𝑠 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡

∗ 𝑀𝑄𝐻𝑆 𝐺𝑃𝐻𝑅
∗ 𝑃𝑜𝑡𝑒𝑛𝑐𝑦 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 (%𝑇𝐻𝐶)
∗ 𝑀𝐴𝐸𝐶 

 
Data Analysis 
 

Quantile regressions compared the median 

individual GPHRs across the three MQHS groups 

for both flower and concentrate products. Quantile 

regressions then compared the mgTHC estimates 

derived from the SHS and MQHS approaches for 

overall consumption from flower products and for 

each MQHS group, and the same was performed 

for concentrate products. All regressions included 

cluster-robust standard errors and were controlled 

for the order of items. Analyses were conducted 

using STATA version 16.1. All distributions are 

described using medians, as the distributions were 

skewed.   

 

RESULTS 
 

Sample Demographics 
 

The sample had a mean age of 39.1 (SD = 16.2) 

years and was 80.0% non-Hispanic White. The 

sample was 48.2% female, 50.6% were employed 

full time, and 55.1% completed an Associate’s 

degree or higher education. Full sample 

demographics have been previously published 

(Borodovsky et al., 2023). 

 

Cannabis Use Characteristics 
 

The average age of cannabis use onset was 

16.5 (SD = 4.7) years. The sample was composed 

of primarily frequent and heavy consumers with 



Multiple Qualitative Hit Size    
 

157 

participants using on average 26.3 (SD = 7.1) days 

in the past month and 6.3 (SD = 1.6) days in the 

past week. Smoking flower was the most common 

method of administration (90.8%), followed by 

vaping concentrate (42.2%), vaping flower 

(20.7%), and dabbing concentrate (18.3%). The 

most common method used to smoke flower was 

joints (37.2%), and the most common method for 

using concentrate was prefilled cannabis 

cartridge (66.9%). Additionally, 50.7% reported 

using either edibles, capsules, liquids, or another 

method. Nearly 71.2% reported using 2 or more 

methods of administration. The median number of 

hits of flower per day was 14 (Q1: 7, Q3: 29), and 

the median number of hits of concentrate per day 

was 7 (Q1: 4, Q3: 14). The median number of 

grams of flower per day was 1 (Q1: 0.4, Q3: 2.3), 

and the median number of grams of concentrate 

per day was 0.2 (Q1: 0.1, Q3: 0.4). 

 

Individual GPHRs Among MQHS Groups 

 

Descriptive statistics can be seen in Table 1. 

The median flower GPHR for those who reported 

taking small (n = 304), medium (n = 2,252), and 

large (n = 827) hits was 0.042g/hit, 0.062g/hit and 

0.093g/hit respectively. Of note, the SHS GPHR 

(0.06) was very similar to the median GPHR 

among the medium hit size group. As shown in 

Figure 1a, participants reporting a large hit size 

for flower had a greater first quantile, median, 

and third quantile GPHR than those reporting a 

medium (Q1: 0.013, 95%CI: [0.006, 0.021]; Q2: 

0.028, [95%CI: 0.016, 0.041]; Q3: 0.041, 95%CI: 

[0.027, 0.056]) or a small hit size (Q1: 0.021, 

95%CI: [0.013, 0.029]; Q2: 0.042, [95%CI: 0.028, 

0.057]; Q3: 0.068, 95%CI: [0.051, 0.086]). Those 

reporting a medium hit size had a greater first 

quantile, median, and third quantile GPHR for 

flower than those reporting a small hit (Q1: 0.008, 

95%CI: [0.003, 0.013]; Q2: 0.014, 95%CI: [0.005, 

0.023]; Q3: 0.027, 95%CI: [0.012, 0.041]).

Figures 1A & 1B. Individual Flower Grams-Per-Hit Ratios (GPHRs) for Each Participant Grouped by Self-
Reported Hit Size; Individual Concentrate Grams-Per-Hit Ratios (GPHRs) For Each Participant Grouped 
by Self-Reported Hit Size.  

 



Cannabis, A Publication of the Research Society on Marijuana             

 

158 

Note. A: The median GPHRs for each hit size group is the GPHR assigned to each hit size group for the 

multiple qualitative hit size (MQHS) GPHR approach. The single hit size (SHS) GPHR approach contains 

only one GPHR (0.06) and is represented to allow comparisons between the GPHRs in the MQHS and SHS 

approaches. * denotes significant difference. B: Individual concentrate grams-per-hit ratios (GPHRs) for 

each participant grouped by self-reported hit size. The median GPHRs for each hit size group is the GPHR 

assigned to each hit size group for the multiple qualitative hit size (MQHS) GPHR approach. The single hit 

size (SHS) GPHR approach contains only one GPHR (0.06) and is represented to allow comparisons between 

the GPHRs in the MQHS and SHS approaches. * denotes significant differences. 

 

 

Table 1. Descriptive Statistics for Individual Grams-Per-Hit Ratios and Milligrams of THC Estimates 

  Mean SD Min Q1 Median Q3 Max Skewness Kurtosis 

Individual Flower GPHR 0.10 0.14 0.00 0.03 0.07 0.13 3.50 12.62 272.27 

Individual Concentrate 

GPHR 0.05 0.07 0.00 0.02 0.03 0.06 0.90 5.93 53.31 

Single Hit Size (SHS) Estimates 

mgTHC per Day 117.97 147.97 1.80 32.34 68.04 144.18 1775.52 3.48 22.60 

mgTHC from Flower 97.25 119.85 1.80 27.00 54.00 115.74 972.00 2.88 13.41 

mgTHC from Concentrate 58.00 80.12 2.12 15.30 32.94 67.20 803.52 4.14 27.48 

Multiple Qualitative Hit Size (MQHS) Estimates 

mgTHC per Day 169.88 248.65 1.26 39.55 91.51 198.47 3081.00 4.58 35.44 

mgTHC from Flower 113.51 153.67 1.26 29.14 61.60 138.31 1276.50 3.42 18.02 

mgTHC from Concentrate 137.02 200.61 4.20 32.80 75.79 150.00 2082.00 4.17 26.96 

Note. THC = delta-9 tetrahydrocannabinol 

 

 For concentrates, the median GPHRs for 

those selecting small (n = 471), medium (n = 849), 

and large (n = 349) hits were 0.024g/hit, 

0.025g/hit, and 0.035g/hit, respectively. The 

GPHR for each MQHS group was larger than the 

SHS GPHR (0.012). As seen in Figure 1b, those 

reporting a large hit size had a greater median 

GPHR than those reporting a medium hit size 

(Q2: 0.008, 95%CI: [0.002, 0.014[), but the GPHR 

did not differ significantly at the first or third 

quantile (Q1: 0.002, 95%CI: [-0.001, 0.006]; 

Q3:0.009,  95%CI: [-0.001, 0.019]). Those 

reporting a large hit size had a greater first 

quantile, median, and third quantile GPHR than 

those reporting a small hit size (Q1: 0.005, 95%CI: 

[0.001, 0.010]; Q2: 0.010, 95%CI: [0.003, 0.016]; 

Q3: 0.016, 95%CI: [0.001, 0.031]). The GPHR for 

those reporting a medium or a small hit size did 

not differ significantly at any quantile (Q1: 0.003, 

95%CI: [-0.0003, 0.006]; Q2: 0.002, 95%CI: [-

0.007, 0.003]; Q3: 0.006, 95%CI: [-0.008, 0.020]).  

 

MQHS vs. SHS Approach for Calculating mgTHC 
 

The overall median mgTHC per day estimate 

for all participants was greater with the MQHS 

GPHR approach than with the SHS approach 

(92.6mg vs 68.0mg respectively; Q2: 22.5, 95%CI: 

[14.8, 30.2]). The mgTHC per day estimate for all 

participants was also greater at the first and third 

quantile with the MQHS GPHR approach than 

the SHS approach (Q1:7.6, 95%CI: [3.9, 11.3]; Q3: 

56.2 95%CI: [49.3, 73.0]).  

Flower. Comparisons of mgTHC estimates 

from flower products resulted in greater overall 

estimates from the MQHS approach than the SHS 

approach at the median and third quantile, but 

not the first quantile (Medians: 60.4mg vs 54mg; 

Q1: 1.6 95%CI: [-1.1, 4.3]; Q2: 6.5 95%CI: [0.9, 

12.1]; Q3: 16.5, 95%CI: [3.8, 29.2]). Separate 

comparisons by MQHS groups showed that among 

those reporting a large hit size, the MQHS 

approach produced greater estimates of mgTHC 

than the SHS approach: 99.9mg vs 72.0mg; Q1: 

15.4 95%CI: [5.9, 24.9]; Q2: 31.2, 95%CI: [12.4, 

50.0]; Q3: 56.2 95%CI: [23.9, 88.5] (Figure 2a). No 

differences between the MQHS and SHS 

approaches in mgTHC were observed among the 



Multiple Qualitative Hit Size    
 

159 

medium hit size group (56.3mg vs 54mg; Q1: 1.2, 

95%CI: [-1.6, 4.1]; Q2: 2.4, 95%CI: [-3.2, 8.1]; Q3: 

5.3, 95%CI: [-8.4, 18.9]) or at the median and third 

quantile for the small hit size group (25.5mg vs 

36.6mg; Q2: -12.1, 95%CI: [-27.6, 3.4]; Q3:-30.2, 

95%CI: [-74.2, 13.8]), but there were significant 

differences at the first quantile for the small hit 

size group (Q1: -5.4, 95%CI: [-9.4, -1.3]). 

Concentrates. Comparisons of mgTHC 

estimates from concentrate products resulted in 

greater overall estimates from the MQHS than 

the SHS approach (73.9mg vs 32.9mg; Q1: 17.2, 

95%CI: [13.9, 20.6]; Q2: 39.9, 95%CI: [31.8, 48.0]; 

Q3: 79.5, 95%CI: [65.3, 93.7]). For each of the 

three MQHS groups, the MQHS approach 

produced larger estimates of mgTHC than the 

SHS approach (Figure 2b; 104.1mg vs 39.1mg; Q1: 

11.4, 95%CI: [6.2, 16.5]; Q2: 66.3, 95%CI: [46.3, 

86.3]; Q3: 45.7, 95%CI: [19.0, 72.3]; 70mg vs 

33.8mg; Q1: 16.0, 95%CI: [11.1, 20.9]; Q2: 35.1, 

95%CI: [24.8, 45.5]; Q3: 67.9, 95%CI: [50.6, 85.2]; 

49.8mg vs 25.2mg; Q1: 32.4, 95%CI: [21.1, 43.9]; 

Q2: 24.0, 95%CI: [11.5, 36.5]; Q3: 125.7, 95%CI: 

[77.8, 173.6] for the large, medium, and small hit 

size groups, respectively). 

Figures 2A and 2B. Estimates of Milligrams of THC (mgTHC) Consumed From Flower and Concentrates; 
Grouped by Grams-Per-Hit Ratio Approach and Qualitative Hit Size 

 

 
Note. A: Estimates of mgTHC consumed from only flower products using both the single hit size approach 

(SHS) and the multiple qualitative hit size approach (MQHS) among each self-reported hit size group 

(small, medium, large). * denotes significant differences between the SHS and MHs approaches. B: 

Estimates of mgTHC consumed from only concentrate products using both the single hit size approach 

(SHS) and the multiple qualitative hit size approach (MQHS) among each self-reported hit size group 

(small, medium, large). * denotes significant differences between the SHS and MHs approaches. 

 



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160 

 

 

DISCUSSION 

 

These findings contribute to the ongoing 

development of survey methods for increasing the 

accuracy of estimating mgTHC consumption. The 

present study illustrates a novel, low-burden 

method of personalizing grams-per-hit ratios 

(GPHRs) to account for varying hit sizes (i.e., 

small, medium, large) when calculating mgTHC 

among cannabis consumers who report their 

consumption in hits/puffs/tokes. This novel 

MQHS GPHR approach accounts for some of the 

variability in hit size among cannabis consumers, 

which in turn improves the accuracy of the 

mgTHC estimate compared to using a single 

GPHR for all consumers. The method used in this 

study to derive MQHS GPHRs provides a 

roadmap for developing standard constants for 

the MQHS approach that will allow researchers to 

ask only one question (i.e., “Do you take a small, 
medium, or large sized hit?”) to determine an 

individual’s GPHR when calculating mgTHC. 

Improving mgTHC estimation methods is crucial 

for precise prevention messaging, assessing 

cannabis policy impact, and evaluating clinical 

trial outcomes on cannabis efficacy and adverse 

reactions.  

Results showed that GPHRs, derived by 

dividing self-reported grams consumed per day by 

hits per day, differed among groups who reported 

taking low, medium, or large sized hits. This 

supports observations from laboratory studies 

that documented individual differences in hit size 

when cannabis is smoked or vaped. (Heishman et 

al., 1989; Matthias et al., 1996; McClure et al., 

2012) For flower products, the GPHRs for the 

three hit size groups clearly differed from each 

other, suggesting strong potential for developing 

standardized MQHS GPHRs for calculating 

mgTHC from self-reported number of hits of 

flower products. The MQHS and SHS approaches 

produced similar mgTHC estimates for those who 

reported medium-sized hits, as the GPHR for the 

medium hit size group in the MQHS approach 

(0.062) was similar to the SHS GPHR (0.06). This 

observation supports the MQHS approach, given 

that the medium hit size likely approximates our 

sample’s average and the SHS GPHR value 

represents the average hit size across laboratory 

studies. For those who reported taking large-sized 

hits, the MQHS approach produced a greater 

mgTHC estimate than the SHS approach, likely 

reflecting more valid individual estimates, as hit 

size impacts the amount of THC consumed. 

(Azorlosa et al., 1995) We did not observe a 

significant difference among those reporting small 

hits (i.e., less mgTHC with the MQHS approach), 

although values were in the expected direction. 

Limited low-end response options for reporting 

grams per day and difficulty estimating small 

quantities of flower may have contributed to this 

null finding. Presumably, many consumers choose 

to report their quantity of use in hits rather than 

grams because they struggle to accurately report 

small numbers of grams. Moreover, the findings 

generally tend to be more extreme at the third 

quantile as compared to the median and findings 

at the first quantile tend to be less extreme, 

making it more difficult to detect differences. We 

believe this is a result of differences being 

amplified or diminished with more or less use (i.e., 

there is less of a difference between one and two 

hits as compared to 10 and 20 hits).  

The findings for estimating mgTHC for 

concentrates indicate more exploration is needed. 

The median GPHR derived for all three MQHS 

groups was larger than the SHS GPHR 

comparison value, which was determined using 

estimates from prior laboratory studies. The large 

hit size group’s GPHR was greater than the small 

and the medium hit size groups at the median, 

which did not differ from each other. However, the 

large hit size group’s GPHR did not differ at the 

first or third quantile from the medium hit size 

group. All three MQHS groups produced greater 

estimates of mgTHC than the SHS approach. 

Generally, consumers struggle to report small 

numbers of grams of concentrate accurately 

(Prince et al., 2018). The response options in our 

survey for the number of grams consumed per day 

likely did not include a low enough quantity 

category, as the lowest was 1/16g, causing a 

potential floor effect and overestimating mgTHC. 

This likely artificially increased estimates for low-

end obfuscated potential differences in GPHRs 

and associated mgTHC estimates between those 

who reported small and medium hit sizes.   

Several additional methodological limitations 

should be noted. The study sampling methodology 

was not designed to be representative of all 

cannabis consumers. Thus, the majority of the 

analytic sample were Non-Hispanic White 



Multiple Qualitative Hit Size    
 

161 

individuals who reported frequent and heavy 

cannabis use. All respondents self-selected to 

participate via an advertisement on Facebook or 

Instagram. Self-report and recall biases may also 

influence the findings.  

 

Conclusions and Future Studies 
 

This study demonstrated a novel approach 

(MQHS GPHR) to account for varying hit sizes 

when using detailed cannabis use survey items to 

estimate mgTHC from smoked or vaped cannabis 

products. The MQHS approach performed well for 

estimating consumption from flower products, but 

more work is needed to test its value for 

concentrate products. We believe these data 

represent an important first step in 

demonstrating how new standard GPHRs can be 

developed for an MQHS approach, such that 

future studies only need to ask about qualitative 

hit size to assign an individual a GPHR. 

Specifically, subsequent studies need to include 

more expansive response options on the lower end 

of consumption to avoid GPHR floor effects. 

Moreover, the GPHRs derived in this study for the 

three MQHS groups for flower products should 

not be used as new standard GPHR estimates 

until these findings are replicated in studies with 

larger and more representative samples. 

Additionally, future laboratory studies should 

evaluate how accurately consumers can estimate 

the number of hits to finish a half-gram of 

cannabis product using their preferred method. 

This would likely involve the participant 

estimating the number of hits to finish a half gram 

prior to consuming any cannabis and the 

researcher observing a participant consume a half 

gram and counting the number of hits they 

consume. Such future studies would help validate 

the methods needed to derive the multiple 

qualitative hit size GPHRs. Future studies that 

incorporate objective measures of consumption 

(e.g., topography, urinalysis) could aide in 

validating the MQHS. Further, studies can assess 

for other cannabinoid use and explore moderators 

(e.g., biological sex differences) that may influence 

mgTHC exposure and dosing effects. Lastly, 

future studies can assess the clarity of the items 

used in this study.  

We hope that this limited demonstration 

stimulates others to investigate similar 

approaches to capturing variability in hit size to 

develop standard GPHRs for this type of multiple 

qualitative hit size approach. Efforts to improve 

cannabis estimation models are sorely needed, 

and accounting for individual variation in hit size 

will improve estimates of mgTHC and facilitate 

more accurate studies of the effects of cannabis 

consumption. 

 

REFERENCES 
 

Azorlosa, J. L., Greenwald, M. K., & Stitzer, M. L. 

(1995). Marijuana smoking: effects of varying 

puff volume and breathhold duration. Journal 
of pharmacology and experimental 
therapeutics, 272(2), 560-569. 

https://doi.org/10.1016/S0022-3565(25)24436-

6  

Borodovsky, J. T., Hasin, D. S., Shmulewitz, D., 

Walsh, C., Livne, O., Aharonovich, E., Struble, 

C. A., Habib, M. I., & Budney, A. J. (2022). 

Typical hits, grams, or joints: evaluating 

cannabis survey measurement strategies for 

quantifying consumption. Cannabis and 
cannabinoid research. 

https://doi.org/10.1089/can.2022.0237  

Borodovsky, J. T., Marsch, L. A., & Budney, A. J. 

(2018). Studying Cannabis Use Behaviors 

With Facebook and Web Surveys: Methods 

and Insights. JMIR Public Health and 
Surveillance, 4(2), e48. 

https://doi.org/10.2196/publichealth.9408  

Borodovsky, J. T., Struble, C. A., Habib, M. I., 

Hasin, D. S., Shmulewitz, D., Walsh, C., 

Livne, O., Aharonovich, E., & Budney, A. J. 

(2023). Exploring survey methods for 

measuring consumption quantities of 

cannabis flower and concentrate products. The 
American Journal of Drug and Alcohol Abuse, 

1-13. 

https://doi.org/10.1080/00952990.2023.224663

5  

Budney, A. J., Borodovsky, J. T., Struble, C. A., 

Habib, M. I., Shmulewitz, D., Livne, O., 

Aharonovich, E., Walsh, C., Cuttler, C., & 

Hasin, D. S. (2022). Estimating THC 

consumption from smoked and vaped cannabis 

products in an online survey of adults who use 

cannabis. Cannabis and cannabinoid research, 

9(2), 688-698.  

https://doi.org/10.1089/can.2022.0238  

Compton, W. M., Han, B., Jones, C. M., & Blanco, 

C. (2019). Cannabis use disorders among 



Cannabis, A Publication of the Research Society on Marijuana             

 

162 

adults in the United States during a time of 

increasing use of cannabis. Drug Alcohol 
Dependence, 204, 107468. 

https://doi.org/10.1016/j.drugalcdep.2019.05.0

08  

Cuttler, C., & Spradlin, A. (2017). Measuring 

cannabis consumption: Psychometric 

properties of the Daily Sessions, Frequency, 

Age of Onset, and Quantity of Cannabis Use 

Inventory (DFAQ-CU). PLoS One, 12(5), 

e0178194. 

https://doi.org/10.1371/journal.pone.0178194  

Davenport, S. (2021). Price and product variation 

in Washington's recreational cannabis 

market. International Journal of Drug Policy, 
91, 102547. 

https://doi.org/10.1016/j.drugpo.2019.08.004  

Hall, W., & Lynskey, M. (2020). Assessing the 

public health impacts of legalizing 

recreational cannabis use: the US experience. 

World Psychiatry, 19(2), 179-186. 

https://doi.org/10.1002/wps.20735  

Heishman, S., Stitzer, M., & Yingling, J. (1989). 

Effects of tetrahydrocannabinol content on 

marijuana smoking behavior, subjective 

reports, and performance. Pharmacology 
Biochemistry & Behavior, 34, 173-179. 

https://doi.org/10.1016/0091-3057(89)90369-9  

Lynch, J., Lorenz, L., Brueggemeyer, J. L., 

Lanzarotta, A., Falconer, T. M., & Wilson, R. 

A. (2021). Simultaneous temperature 

measurements and aerosol collection during 

vaping for the analysis of delta(9)-

tetrahydrocannabinol and vitamin e acetate 

mixtures in ceramic coil style cartridges. 

Frontiers in Chemistry, 9, 734793. 

https://doi.org/10.3389/fchem.2021.734793  

Matthias, P., Tashkin, D., Marques-Magallanes, 

J., Wilkins, J., & Simmons, M. (1996). effects 

of varying marijuana potency on deposition of 

tar and ⌬ 9 -THC in the lung during smoking. 

Pharmacology Biochemistry & Behavior, 58, 

1145-1150. https://doi.org/10.1016/s0091-

3057(97)00328-6  

McClure, E. A., Stitzer, M. L., & Vandrey, R. 

(2012). Characterizing smoking topography of 

cannabis in heavy users. 

Psychopharmacology, 220(2), 309-318. 

https://doi.org/10.1007/s00213-011-2480-4  

Prince, M. A., Conner, B. T., & Pearson, M. R. 

(2018). Quantifying cannabis: A field study of 

marijuana quantity estimation. Psychology of 

Addictice Behaviors, 32(4), 426-433. 

https://doi.org/10.1037/adb0000370  

Qualtrics. (2025). Qualtrics software (Version April 

2025) [Computer software]. Qualtrics. 

https://www.qualtrics.com 

Rajapaksha, R., Hammonds, R., Filbey, F., 

Choudhary, P. K., & Biswas, S. (2020). A 

preliminary risk prediction model for cannabis 

use disorder. Preventive Medicine Reports, 20, 

101228. 

https://doi.org/10.1016/j.pmedr.2020.101228  

Sikorski, C., Leos-Toro, C., & Hammond, D. 

(2021). Cannabis consumption, purchasing 

and sources among young Canadians: The 

Cannabis Purchase and Consumption Tool 

(CPCT). Substance Use & Misuse, 56(4), 449-

457. 

https://doi.org/10.1080/10826084.2021.187914

2  

Spindle, T. R., Bonn-Miller, M. O., & Vandrey, R. 

(2019). Changing landscape of cannabis: novel 

products, formulations, and methods of 

administration. Current Opinion in 
Psychology, 30, 98-102. 

https://doi.org/10.1016/j.copsyc.2019.04.002  

Varlet, V., Concha-Lozano, N., Berthet, A., 

Plateel, G., Favrat, B., De Cesare, M., Lauer, 

E., Augsburger, M., Thomas, A., & Giroud, C. 

(2016). Drug vaping applied to cannabis: Is 

"Cannavaping" a therapeutic alternative to 

marijuana? Scientific Reports, 6, 25599. 

https://doi.org/10.1038/srep25599 

 

Funding and Acknowledgements: This work was 

supported by the National Institute on Drug 

Abuse (NIDA) R01-DA050032, T32-DA037202, 

P30- DA037202. The funding sources were not 

involved in the study design; collection, analysis, 

and interpretation of data; writing of the report; 

or in the decision to submit the article for 

publication. Drs. Alan Budney and Jacob 

Borodovsky report funding from NIDA as a 

potential conflict of interest. Dr. Budney is a 

member of the Scientific Review Board of Canopy 

Growth and a consultant for Jazz 

Pharmaceuticals. All other authors of this 

manuscript have no conflicts of interest to 

report.. We would like to thank all the 

participants in this study.  

 

 



Multiple Qualitative Hit Size    
 

163 

Copyright:  © 2025 Authors et al. This is an open 

access article distributed under the terms of the 

Creative Commons Attribution License, which 

permits unrestricted use, distribution, and 

reproduction, provided the original author and 

source are credited, the original sources is not 

modified, and the source is not used for 

commercial purposes. 

 

Citation: Habib, M. I., Budney, A. J., Struble, 

C. A., Hasin, D. S., Livne, O., Aharonovich, 

E., Wisell, C., Fragione, S. N., & Borodovsky, 

J. T. (2025). Estimating cannabis 

consumption in milligrams of THC from self-

reported hit size. Cannabis, 8(2), 153 - 163.  

https://doi.org10.26828/cannabis/2025/00028

5 

 

Issue Date: July 15, 2025 

 

 

https://creativecommons.org/licenses/by/4.0/