BDI	Beck Depression Inventory
BSI	Beck Scale for Suicidal Ideation
CI	Confidence Intervals
FACIT-Sp	Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being Scale
FDA	U.S. Food and Drug Administration
GRADE	Grading of Recommendation Assessment, Development and Evaluation
GRID-HAMD-17	GRID-Hamilton Depression Rating Scale
HAD-D	Hospital Anxiety and Depression Scale—Depression subscale
HADS-T	The Hospital Anxiety and Depression Scale—Total
HAM-D	Hamilton Depression Rating Scale
HAM-D-17	17-item Hamilton Depression Rating Scale
LSD	lysergic acid diethylamide
LTI	Life-threatening illness
MADRS	Montgomery-Asberg Depression Rating Scale
MADRS-SI	Montgomery–Åsberg Depression Rating Scale—Suicidal Ideation
MAPS	Multidisciplinary Association for Psychedelic Studies
MDD	Major Depressive Disorder
MDMA	3,4-methylenedioxymethamphetamine
MDPI	Multidisciplinary Digital Publishing Institute
MEQ-30	Mystical Experience Questionnaire
NIH	National Institute of Health
NIH-HEALS	National Institute of Health—Healing Experience of All Life Stressors
NMDA	N-methyl-D-aspartate
PAT	Psychedelic-assisted therapy
PHQ-9	Patient-reported depression
PLWC	People living with cancer
PRISMA	preferred reporting items for systematic reviews and meta-analyses
RCT	Randomized controlled trials
RoB	Risk of bias
STAI	State-Trait Anxiety Inventory