A number of scientific studies by Roland R. Griffiths and other researchers have concluded that high doses of psilocybin and other classic psychedelics trigger mystical experiences in most research subjects. A 2011 study from Johns Hopkins University identified mystical experiences by means of psychometric questionnaires, including the States of Consciousness Questionnaire (using only a relevant subset of items), the Mysticism Scale, and the APZ questionnaire. The researchers observed that psilocybin "occasions personally and spiritually significant mystical experiences that predict long-term changes in behaviors, attitudes and values."