Missing Pharmacokinetic Samples Were Separate From Complete Cognitive Outcomes
The study imputed missing pharmacokinetic data while reporting no missing cognitive or psychopathological outcomes. Missing blood values should not be described as missing memory scores.
Different datasets had different completeness
The authors reported thirty-seven missing pharmacokinetic data points out of 360, approximately 10%, and used multiple imputation by chained equations. They explicitly stated that cognitive and psychopathological outcome data were complete. These are different measurements with different analytical handling.
Imputation does not create a collected specimen
A modeled replacement supports analysis under its assumptions but is not a newly measured concentration. Interpretation of pharmacokinetic exposure and its association with outcomes should retain that distinction. Conversely, missing concentration data do not mean that the primary memory observations were guessed or replaced by the same procedure.
Keep null mechanisms and measured outcomes apart
The report found no evidence that CBD increased plasma exposure to THC or 11-hydroxy-THC under this protocol, despite worse delayed recall. That does not prove a particular alternative mechanism. A careful summary distinguishes observed cognition, symptom ratings, measured concentrations and imputed values rather than compressing all uncertainty into a claim that the trial had incomplete outcomes.
Related analysis: the schizophrenia cannabis-challenge findings.
Research cited
Chesney and colleagues (2025). Does cannabidiol reduce the adverse effects of cannabis in schizophrenia? A randomised, double-blind, cross-over trial. DOI: 10.1038/s41386-025-02175-3.
