Skip to content

Cannabis’s Link to Schizotypy: Phenomenon, Measurement Bias, or Delusion?

Brianna R. Altman, Mitch Earleywine, Maha N. Mian, Dev K. Dalal

Cannabis July 11, 2022 DOI: 10.26828/cannabis/2022.02.003 (opens in new tab)

Relevant Not relevant

Study at a glance

AI-extracted from the abstract
Characteristics Cross-sectional study Peer reviewed
Sample size 705
Population Participants recruited from Amazon's MTurk platform
Topics Cannabis
Keywords Schizotypy Psychopathology Psychosis Delusion Clinical psychology Schizotypal personality disorder Developmental psychology
Key findings Cannabis users and non-users did not differ significantly on total SPQ-B scores or its three established subscales; only the odd or unusual behavior factor showed differences, which were reduced after removing a potentially biased item.

Abstract

Links between cannabis use and psychosis generate research and media attention. Cannabis users have outscored non-users on the Schizotypal Personality Questionnaire-Brief (SPQ-B) in multiple studies, but previous work suggests that groups do not differ if biased items are removed. The present study examined links between schizotypal personality and cannabis use in a large sample recruited from Amazon's MTurk platform (N = 705). Over 500 participants reported lifetime cannabis exposure. Of those, 259 participants reported current cannabis use, and on average, used 4.53 days per week. Users and non-users failed to differ significantly on total SPQ-B scores or any of the three established subscales. The null results inspired a re-examination of the SPQ-B's factor structure, which identified a novel 3-factor solution (difficulty opening up to others, hyperawareness, and odd or unusual behavior). Only the "odd or unusual behavior" factor showed cannabis-related differences, but a differential item functioning test revealed that one subscale item showed potential bias against users. Removing this item diminished group differences. These results suggest that links between schizotypy and cannabis use require cautious interpretation with careful attention to potential measurement bias. In addition, the SPQ-B might have an alternative factor structure that could help answer important questions in psychopathology.

Comparable studies

Other cross-sectional and survey studies on cannabis, most cited first.

Study Year Design Participants
Cannabis use before age 15 and subsequent executive functioning 104 chronic cannabis users (49 early-onset before age 15, 55 late-onset after age 15)... 2011 Observational cross-sectional study n = 148
Patterns of simultaneous polysubstance use in drug using university students Drug-using university students 2006 Cross-sectional survey n = 149
Persisting Reductions in Cannabis, Opioid, and Stimulant Misuse After Naturalistic Psychedelic Use: An Online Survey Online survey respondents 2020 Cross-sectional survey
User perceptions of the benefits and harms of hallucinogenic drug use: A web-based questionnaire study Users of hallucinogenic drugs who completed a web-based questionnaire 2010 Cross-sectional survey n = 600
Illicit Use of LSD or Psilocybin, but not MDMA or Nonpsychedelic Drugs, is Associated with Mystical Experiences in a Dose-Dependent Manner Adults recruited from the MAPS website and newsletter, most reporting use of various... 2012 Cross-sectional survey n = 337

Citations in the library

Cites 4

Related reading

Explore topics

Cannabis