Protocol - Patterns of Substance Use – Calendar Based Method for Detailed Cannabis Use

Description

The Calendar Based Method for Detailed Cannabis Use from Petrilli et al. (2024) is a two-part, interviewer-administered questionnaire that captures type, amount, and frequency of cannabis used. In the first part, respondents report the types and amount of cannabis used over the previous 3 months along with method of consumption (e.g., bong, joint, joint with tobacco) There are a series of five pictures to help respondents identify type and amount of cannabis used. In the second part, frequency of use is captured with a timeline followback calendar using the results of part 1. Standard THC units (e.g., 5 milligram dose) should be calculated from the type of cannabis, potency, and frequency of use as described in the THC 5 mg standard protocol.

Specific Instructions

When there is an interest in assessing the use of cannabis for medical reasons, the PhenX Substance Use and Recovery Working Group (WG) recommends that the term "cannabis" could be replaced with "medical cannabis" to specifically capture use of products for medical use.

The Substance Use and Recovery WG notes that the Calendar Based Method for Detailed Cannabis Use from Petrilli et al. (2024) can also be used to capture polysubstance use. Given the time needed to complete this method when assessing multiple substances, investigators should consider feasibility in assessing all substances used when studying polysubstance use and tailor assessment to the specific research question. Investigators should review similar calendar-based methods (e.g., Timeline Followback (TLFB) protocol) for examples of capturing use of substances other than cannabis.

The Substance Use and Recovery WG notes this protocol can be used to calculate standard THC units (e.g., (grams of THC consumed (e.g., per week) X cannabis potency (percent)) / 0.005 gram = number of standard THC units).

Protocols may include terms and language that could be triggering to respondents. Investigators are encouraged to have resources in place to help respondents cope with triggers as needed.

Terminology related to substances, substance use, and recovery is fluid. Updates in protocol language may be appropriate based on circumstance. Suggestions for revision have been offered to update answer responses or other components of the questionnaires to account for the constantly changing landscape. These suggestions have not been tested or validated in research studies but may be considered by investigators to enhance relevance.

Availability

This protocol has limited availability; permission required for use.

Protocol

Calendar Based Method for Detailed Cannabis Use from Petrilli et al. (2024)

Detailed instructions for the Calendar Based Method for Detailed Cannabis Use from Petrilli et al. (2024) can be found in the supporting information of the source publication: onlinelibrary.wiley.com/action/downloadSupplement?doi=10.1111%2Fadd.16405&file=add16405-sup-0001-Supplementary_materials.docx

Calculation of Standard THC Units

(Grams of THC consumed (e.g., per week) X cannabis potency (percent)) / 0.005 gram = number of standard THC units

Personnel and Training Required

Requirements for training and personnel are described in Petrilli et al. (2024) (see “Source”).

Equipment Needs

None

Requirements

Requirement Category	Required
Major equipment	No
Specialized training	No
Specialized requirements for biospecimen collection	No
Average time of greater than 15 minutes in an unaffected individual	Yes

Mode of Administration

Interviewer-administered questionnaire

Lifestage

Adolescent, Adult, Pregnancy

Participants

Adolescents and adults, ages 16 and older

Selection Rationale

The Calendar Based Method for Detailed Cannabis Use from Petrilli et al. (2024) builds on the well-established, valid, and reliable Timeline Followback paradigm to collect more detailed information on the amount and type of cannabis which can be used to calculate standard tetrahydrocannabinol (THC) units.

Language

English

Standards

Standard	Name	ID	Source

Derived Variables

None

Process and Review

Not Applicable

Protocol Name from Source

Petrilli, K., Lawn, W., Lees, R., Mokrysz, C., Borissova, A., Ofori, S., Trinci, K., Dos Santos, R., Leitch, H., Soni, S., Hines, L. A., Lorenzetti, V., Curran, H. V., & Freeman, T. P. (2024). Addiction (Abingdon, England), 119(4), 772–783.

Source

General References

Cooper, A. M., Sobell, M. B., Sobell, L. C., & Maisto, S. A. (1981). Validity of alcoholic's self-reports: duration data.International Journal of the Addictions, 16(3), 401–406.
https://doi.org/10.3109/10826088109038841

Norberg, M. M., Mackenzie, J., & Copeland, J. (2012). Quantifying cannabis use with the timeline followback approach: a psychometric evaluation. Drug and Alcohol Dependence, 121(3), 247–252.
https://doi.org/10.1016/j.drugalcdep.2011.09.007

Robinson, S. M., Sobell, L. C., Sobell, M. B., & Leo, G. I. (2014). Reliability of the Timeline Followback for cocaine, cannabis, and cigarette use. Psychology of Addictive Behaviors, 28(1), 154–162.
https://doi.org/10.1037/a0030992

Sobell, L. C., Brown, J., Leo, G. I., & Sobell, M. B. (1996). The reliability of the Alcohol Timeline Followback when administered by telephone and by computer.Drug and Alcohol Dependence, 42(1), 49–54.
https://doi.org/10.1016/0376-8716(96)01263-x

Protocol ID

510305

Variables

Export Variables

Variable Name	Variable ID	Variable Description	dbGaP Mapping

Assessment of Substance Use and Substance Use Disorders

Measure Name

Patterns of Substance Use

Release Date

January 30, 2025

Definition

Instruments used separately to assess patterns of substance use in adolescents and adults.

Purpose

The purpose of this measure is to determine patterns of tobacco, binge drinking, and other drug use in adolescents and adults.

Keywords

tobacco, marijuana, medical cannabis, substance use, addiction, tetrahydrocannabinol, THC, cannabidiol, CBD

Measure Protocols

Protocol ID	Protocol Name
510303	Patterns of Substance Use - Adolescents
510304	Patterns of Substance Use - Adults - Binge-Drinking
510305	Patterns of Substance Use – Calendar Based Method for Detailed Cannabis Use
510306	Patterns of Substance Use - Alcohol and/or Drug Use
510307	General Cannabis Use
510308	Cannabis Products, Types, and Modes of Use
510310	Assessment of Cannabis Use Disorder