Table 3.

Endorsement frequencies for DISCO items identified in Table 2

Item description	% Score = 0 (marked)	% Score = 1 (minor)	% Score = 2 (unaffected)	% Missing/un-rateable
Anxiety	52.9	25.5	21.6	0
One-sided social approaches	44.4	34	7.8	13.7
Temper tantrums	35.3	30.7	33.3	0.7
Changeable mood	34	27.5	38.6	0
Lack of co-operation	33.3	34	32	0.7
Blaming other people*	33.3	18.3	45.8	2.6
Embarrassing remarks in public	30.7	28.1	33.3	7.8
Apparently manipulative behaviour*	27.5	24.2	47.7	0.7
Awareness of own identity*	26.8	24.8	47.1	1.3
Behaviour in public places	21.6	29.4	49	0
Difficulties with other people	16.3	14.4	67.3	2
Repetitive acting out roles*	15	11.8	20.3	52.9
Fantasising, lying, cheating, stealing*	13.7	17	67.3	2
Inappropriate sociability (rapid, inexplicable changes from loving to aggression)*	13.1	18.3	46.4	22.2
Using age peers as mechanical aids, bossy and domineering*	7.8	10.5	80.4	1.3
Socially shocking behaviour*	7.8	7.2	84.3	0.7
Harassment of others	7.2	10.5	80.4	2

Items that were included in Wing and Gould’s draft 15-item PDA list are designated with an asterisk. Items are sorted from most to least commonly rated as ‘marked difficulties’ within the sample (N = 153). The 11 DISCO PDA items deemed most useful in identifying PDA are shown in bold. Two items included in this list had specific scoring rules. ‘Repetitive acting out roles’ was only scored in the clear presence of some degree of apparent imaginative activities (rated across two separate DISCO items), and was un-rateable for over 50 % of the sample. ‘Inappropriate sociability (rapid, inexplicable changes from loving to aggression)’ was only rateable in the presence of interactions with peers, coded in a separate item