The form and function of challenging behaviours.

Aspects of the topography and behavioural function underlying the challenging behaviours of all people with learning disabilities and challenging behaviour (n = 70) in a defined geographical area were investigated. Results indicated that: (1) more severe challenging behaviours were shown by people with more severe disabilities; (2) a significant minority (44%) of people showed more than one form of challenging behaviour, this rising to 79% among people with more severe challenging behaviours; and (3) cross-sectional analyses revealed specific clusters of problematic, aggressive and self-injurious behaviours. Analysis of information derived from the Motivation Assessment Scale (MAS) indicated that (5) the most common functions of challenging behaviours appeared to be 'self-stimulation' (for self-injury, destructiveness and 'other' challenging behaviours) and securing the attention of carers (for aggressive behaviours). However, (6) parametric analyses failed to identify any consistent relationships between the form and function of an individual's challenging behaviour for aggressive, destructiveness and 'other' challenging behaviours, but (7) clients with self-injurious behaviour were significantly more likely to score highly on the 'self-stimulation' sub-scale than other sub-scales of the MAS. Finally, (8) significant consistency of behavioural functions across different forms of challenging behaviours shown by the same individual were found for the two combinations of aggressive-destructive behaviours and self-injury-'other' behaviours.