Assessing indirect aggression in aggressors and targets: Spanish adaptation of the Indirect Aggression Scales

In recent years, there has been increasing interest in indirect aggression as the most common aggressive behaviour in adulthood. Despite this interest, there are not a great many instruments for measuring this behaviour in adults. The aim of our study was to develop the Spanish adaptation of one of the few instruments that does exist: the Indirect Aggression Scale, in its aggressor and target versions. The analysis of these scales in a sample of 935 university students showed that the aggressor and target versions of the scales had good reliabilities, but that a one-factor structure seemed more feasible than the three-factor structure initially proposed. Taking this one-dimensionality, we developed short versions of the scales, which also showed good reliabilities. The aggressor version presented good convergent validity with direct aggression and impulsivity measures. Finally, none of the scales showed differences associated with sex.