Differentiating new cannabis use from residual urinary cannabinoid excretion in chronic, daily cannabis users.

ABSTRACT:

Aims

To develop and validate empirically a mathematical model for identifying new cannabis use in chronic, daily cannabis smokers.

Design

Models were based on urinary creatinine-normalized (CN) cannabinoid excretion in chronic cannabis smokers.

Setting

For model development, participants resided on a secure research unit for 30 days. For model validation, participants were abstinent with daily observed urine specimens for 28 days.

Participants

A total of 48 (model development) and 67 (model validation) daily cannabis smokers were recruited.

Measurements

All voided urine was collected and analyzed for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) by gas chromatography-mass spectrometry (GCMS; limit of quantification 2.5 ng/ml) and creatinine (mg/ml).

SUBMITTER: Schwilke EW 

PROVIDER: S-EPMC3461262 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature