“…The following demographic factors and lifetime use variables served as covariates in our analyses: sex (male or female), age (18–25, 26–34, 35–49, 50 or older), educational attainment (less than high school, some high school or high school graduate, some college or above), self-reported engagement in risky behavior (never, seldom, sometimes, or always), annual household income (less than $20,000, $20,000–$49,999, $50,000–$74,999, $75,000 or more), marital status (married, divorced/separated, widowed, or never married), survey year (2002–2020), and lifetime use of various substances [MDMA/ecstasy, other classic psychedelics (LSD, peyote, and mescaline), other illegal substances (cocaine, heroin, PCP, inhalants) and other commonly misused legal/medicinal substances (pain relievers, tranquilizers, stimulants, sedatives, and marijuana)]. These exact covariates have been used in prior population-based survey studies investigating race, psychedelic use, and deleterious outcomes ( 11 , 12 ).…”