Purpose. The Gudjonsson Suggestibility Scale (GSS; Gudjonsson, 1984, 1997) is a well-established forensic tool for measuring interrogative suggestibility. However, one restriction of this tool is that it requires an extensive testing procedure. The present study examined whether shorter versions of the GSS yield similar results as the original GSS procedure.
Methods. One group (N=20) was given a shortened version of the GSS that consisted of an immediate recall test and the specific questions. GSS scores in this group were compared with those in a group (N=20) that had the standard procedure which includes a retention interval and immediate and delayed recall tests. A third group (N=20) was administered a shortened procedure in which the 20 GSS questions immediately followed the GSS story. In the fourth group (N=20), participants were given the retention interval, but no recall tests were administered.
Results. ANOVA showed no differences in GSS scores amongst the four groups. Post hoc power analyses indicated that these non-significant findings were not the result of a power problem and that larger sample sizes are expected to yield comparable results. Further analyses showed that neither the retention delay nor the recall tests affected suggestibility scores.
Conclusions. These results suggest that shortened procedures for administering the GSS may be employed in situations where time is a key factor.