The ASC scale has several different forms, including:
Abnorme / Aussergewöhnliche Psychische Zustände (APZ; Abnormal Mental States) – the original three-dimensional version (1975)
OAV (Ozeanische Selbstentgrenzung (OSE), Angstvolle Ich-Auflösung (AIA), Visionäre Umstrukturierung (VUS)—translated to Oceanic Boundlessness, Dread of Ego Dissolution, Visionary Restructuralization; 3D-ASC) – the revised three-dimensional version (1989)
Bewüsstseinstrübung und Akustische Halluzinationen (BETA) – supplemental scale with two additional dimensions—auditory alterations (AUA) and vigilance reduction (VIR) (undated)
5D-ASC – expanded five-dimensional version and combination of OAV and BETA (1999)
11-ASC – revised 11-factor version (2010)
3D-ASCr – revised three-dimensional version (2025)
The 5D-ASC is the most widely used, followed by the 11-ASC version, based on literature citation counts in 2022.
History
The original APZ was first described by Adolf Dittrich in 1975 and was among the earliest scales for assessing hallucinogen effects. The OAV (3D-ASC) was developed and described by I. Bodmer in 1989. BETA was later developed by Dittrich and colleagues and then the OAV and BETA were combined by them to create the 5D-ASC in 1999. The 11-ASC was described by Franz X. Vollenweider and colleagues in 2010. The 3D-ASCr scale was described by Matthias Liechti and colleagues in 2025.
1234Herrmann Z, Earleywine M, De Leo J, Slabaugh S, Kenny T, Rush AJ (2023). "Scoping Review of Experiential Measures from Psychedelic Research and Clinical Trials". J Psychoactive Drugs. 55 (4): 501–517. doi:10.1080/02791072.2022.2125467. PMID36127639.
123456789Studerus E, Gamma A, Vollenweider FX (August 2010). "Psychometric evaluation of the altered states of consciousness rating scale (OAV)". PLoS One. 5 (8) e12412. doi:10.1371/journal.pone.0012412. PMC2930851. PMID20824211. Dittrich's APZ (Abnormal Mental States) questionnaire [1]–[4] and its revised versions, OAV [5] and 5D-ASC [6], [7], are among the most widely used self-report questionnaires for assessing subjective experiences of ASC in retrospect. Although originally developed in German, these questionnaires have been translated into many different languages and applied internationally in approximately 70 experimental studies. The majority of these studies have used these questionnaires to assess ASC induced by psycho-active drugs, particularly psilocybin (eg [8]), ketamine [9], MDMA (eg [10]), and N,N-dimethyltryptamine (DMT) (eg [11]), but several studies have also assessed non-pharmacologically induced ASC, such as ASC induced by endogenous psychosis [12], sensory deprivation [13], mind machines [14], and monochrome sounds [15]. [...] The original version, APZ, contains 158 dichotomous items covering a broad range of phenomena potentially occurring during ASC. It was originally developed by Dittrich [1]–[4] [...]
12Dittrich, A. (1975). Zusammenstellung eines fragebogens (APZ) zur erfas‐sung abnormer psychischer zustände [construction of a question‐naire (APZ) for assessing abnormal mental states]. Z Klin Psychol Psychiatr Psychother, 23, 12. https://scholar.google.com/scholar?cites=8870873145239709113
↑Dittrich, A. Ätiologie-unabhängige Strukturen veränderter Wachbewußtseinszustände: Ergebnisse empirischer Untersuchungen über Halluzinogene I. und II. Ordnung, sensorische Deprivation, hypnagoge Zustände, hypnotische Verfahren sowie Reizüberflutung; 119 Tabellen. (Enke, 1985)
12Dittrich A (July 1998). "The standardized psychometric assessment of altered states of consciousness (ASCs) in humans". Pharmacopsychiatry. 31 Suppl 2: 80–84. doi:10.1055/s-2007-979351. PMID9754838.
12Bodmer I (1989) Konstruktion des Fragebogens OAV zur quantitativen Erfassung von aussergewöhnlichen Bewusstseinszuständen (ABZ). Unpublished Lizentiatsarbeit [Master's-Thesis equivalent]. University of Zurich, Zurich.
12Bodmer I, Dittrich A and Lamparter D (1994) Aussergewöhnliche Bewusstseinszustände—ihre gemeinsame Struktur und Messung. In: Dittrich A, Hofmann A and Leuner H (eds) Welten Des Bewusstseins. Bd. 3. Experimentelle Psychologie, Neurobiologie Und Chemie. Berlin, Germany: VWB—Verlag für Wissenschaft und Bildung. https://scholar.google.com/scholar?cluster=15632949336738292786