Turn on, Tune in, and Drop out: Predictors of Attrition in a Prospective Observational Cohort Study on Psychedelic Use
In a prospective web-based cohort of psychedelic users (baseline n=654), attrition at four weeks was predicted by baseline demographics (age and educational level) and personality traits (lower conscientiousness and higher extraversion), while baseline attitudes toward psychedelics and the intensity of challenging acute experiences did not predict dropout. These results align with attrition patterns seen in other longitudinal research and suggest that dropout in naturalistic psychedelic studies is unlikely to be driven by advocacy or negative drug experiences, reducing concerns about systematic bias.
Authors
- Robin Carhart-Harris
- Mendel Kaelen
- Hannes Kettner
Published
Abstract
Background
The resurgence of research and public interest in the positive psychological effects of psychedelics, together with advancements in digital data collection techniques, have brought forth a new type of research design, which involves prospectively gathering large-scale naturalistic data from psychedelic users; that is, before and after the use of a psychedelic compound. A methodological limitation of such studies is their high attrition rate, particularly owing to participants who stop responding after initial study enrollment. Importantly, study dropout can introduce systematic biases that may affect the interpretability of results.
Objective
Based on a previously collected sample (baseline n=654), here we investigated potential determinants of study attrition in web-based prospective studies on psychedelic use.
Methods
Logistic regression models were used to examine demographic, psychological trait and state, and psychedelic-specific predictors of dropout. Predictors were assessed 1 week before, 1 day after, and 2 weeks after psychedelic use, with attrition being defined as noncompletion of the key endpoint 4 weeks post experience.
Results
Predictors of attrition were found among demographic variables including age (β=0.024; P=.007) and educational levels, as well as personality traits, specifically conscientiousness (β=–0.079; P=.02) and extraversion (β=0.082; P=.01). Contrary to prior hypotheses, neither baseline attitudes toward psychedelics nor the intensity of acute challenging experiences were predictive of dropout.
Conclusions
The baseline predictors of attrition identified here are consistent with those reported in longitudinal studies in other scientific disciplines, suggesting their transdisciplinary relevance. Moreover, the lack of an association between attrition and psychedelic advocacy or negative drug experiences in our sample contextualizes concerns about problematic biases in these and related data.
Research Summary of 'Turn on, Tune in, and Drop out: Predictors of Attrition in a Prospective Observational Cohort Study on Psychedelic Use'
Introduction
Psychedelic substances such as mescaline, psilocybin and dimethyltryptamine have re-emerged in scientific and public discourse, prompting a parallel rise in naturalistic, web-based prospective studies that collect before-and-after data around planned psychedelic experiences. These designs offer ecological validity, efficient recruitment and low cost, but they lack experimental control and are vulnerable to self-selection and high attrition, which can introduce systematic bias and threaten the interpretability of results. Hübner and colleagues used data from a previously published prospective cohort of psychedelic users to investigate predictors of study noncompletion. Their specific interest was whether baseline positive attitudes toward psychedelics or the intensity of challenging acute experiences predicted dropout, alongside demographic and psychological factors that prior longitudinal research in other domains has linked to attrition (for example, younger age, lower education, unemployment, poorer mental health and low conscientiousness). The analysis was exploratory and aimed to quantify which variables most strongly associated with nonresponse at the key 4-week endpoint.
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Study Details
- Study Typeindividual
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- APA Citation
Hübner, S., Haijen, E., Kaelen, M., Carhart-Harris, R. L., & Kettner, H. (2021). Turn on, Tune in, and Drop out: Predictors of Attrition in a Prospective Observational Cohort Study on Psychedelic Use. Journal of Medical Internet Research, 23(7), e25973. https://doi.org/10.2196/25973
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