Multiple susceptibility testing: is it helpful?

This study explored whether or not the use of combined group and individually administered susceptibility tests improve the predictive power over the use of a singly administered test. Two hundred and eighty undergraduates were assigned to one of five groups: Group 1 received the HGSHS: A and then the SHSS:C; Group 2 the CIS and SHSS:C; Group 3 the HGSHS: A and the SHCS:A; Group 4 received the CIS and the SHCS:A; and Group 5 was tested on the SHSS:C alone. After the susceptibility screening the subjects were hypnotized and tested on four types of target hypnotic behaviors. From the RSPSHS:I&II the following four factors were chosen (1) cognitive distortion, (2) positive hallucination, (3) negative hallucination, (4) dreams and regression. The items were matched on difficulty level. The data were subjected to a series of stepwise multiple regression and logistic regression analyses. The results confirmed previous research; i.e., (1) The SHSS:C is the best single measure, (2) the SHCS:A is a poor substitute for the SHSS:C; (3) the HGSHS:A is not adequate substitute for SHSS:C; (4) the CIS is weak in predictive power compared to the HGSHS:A; (5) Only for a weak measure such as SHCS:A does combined testing produce an advantage; (6) There appear to be no warm-up effects for SHSS:C when preceded by HGSHS:A.