Can a hair cannabinoid group explain symptoms at the time of an incident?

Hair analysis can contribute to an exposure history. A questionnaire can describe the experiences a participant reports. A study using both illustrates why an association between them does not locate a symptom at a specific hour.

How the study formed exposure groups

Morgan and Curran analyzed hair from 140 people and compared groups defined by cannabinoid findings. For participants with THC findings they used a THC metabolite as an additional inclusion criterion, and they excluded the small group with CBD alone from the main comparison. Participants in the THC-only group reported more unusual experiences on one questionnaire measure than the THC-plus-CBD and no-detected-cannabinoid groups.

What a timeline would require

The researchers did not assign cannabis products or conduct an acute dosing experiment. The hair result depended on the assay’s detection threshold and did not supply a moment-by-moment exposure record. To evaluate symptoms around an incident, put contemporaneous accounts, examination notes and any time-linked testing on the same timeline. The questionnaire and hair data in this study address a different question from the origin of symptoms at a particular moment.

Morgan and Curran, British Journal of Psychiatry