The hypnosis-testing format (individual vs. group) did not affect the size of the hypnotizability and absorption relationship. Individual testing formats tended to have a higher mean effect size than group testing formats, however these differences were not statistically significant. The results suggest that there is no discernible difference in using a group or individual test format. Accordingly from a cost effectiveness standpoint it may be more cost-effective and efficient to use group hypnosis tests than individually administered hypnosis scales, at least for initial or preliminary screenings.

The type of hypnotic susceptibility scale had a substantial impact on the hypnotizability and absorption scale relationship, accounting approximately 25% of the variance, r = .411. The wording of the hypnotizability measures, item content, and emphasis on certain areas over others, varies a large amount from scale to scale. For example, while the Stanford C scale covers much of the same content areas as the Harvard Group Scale, there is a stronger emphasis on cognitively oriented items over ideomatic and challenge items. Similarly the HIP has several unique and at times controversial items (e.g., the eye roll task) not covered in other hypnotic susceptibility scales.

As a result, when investigating the role of absorption (and possibly other personality dimensions) with hypnotizability, it may be inappropriate to use only one measure of hypnotizability. By using more than one measure of hypnotizability ensures that a wider sample of hypnotic experience is addressed.