The Harvard Group Scale of Hypnotic Susceptibility and related instruments: individual and group administrations

The Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A), Tellegen's Absorption Scale (TAS); Dissociative Experiences Scale (DES); and Phenomenology of Consciousness Inventory (PCI) were administered either individually or in groups. Eighty students from undergraduate Introduction to Psychology classes were randomly assigned to 1 of the 2 administration conditions with 40 students each. Although there was a general trend of differential item difficulty levels across the 2 administration conditions, a variety of results (descriptive characteristics, reliability, and validity) point to the similarity of behavioral and subjective responses to hypnosis in the 2 conditions. The TAS, DES, and PCI also produced similar results across both conditions of administration.