Detecting subgroups in children diagnosed with pervasive developmental disorder - not otherwise specified

Abstract

Hierarchical cluster analyses were used to detect three subgroups in a sample of children with pervasive developmental disorder--not otherwise specified (PDD-NOS) evaluated at ages 2 and 4. At age 2, Cluster 1 demonstrated few autism symptoms and high cognitive scores; 60% no longer met criteria for PDD at 4. Cluster 2 exhibited more autism symptoms and lower cognitive scores at 2; 89.5% met criteria for ASD at 4. Cluster 3 had the lowest cognitive scores and most impaired social/communication skills at 2, but no repetitive behaviors; 60% diagnosed with Autistic Disorder at 4. Results shed light on outcomes for different PDD-NOS types and raise questions regarding the increased importance of repetitive behaviors in DSM-5.

Figure 1

Methods: Phase I cluster analysis dendrogram

Figure 2

Results: Phase II cluster analysis dendrogram and scree plot

Figure 3

ADOS item A6 “Use of Other’s Body to Communicate” scores by cluster. 0 = No use of another’s body to communicate 1 = Takes another person’s hand and leads him/her places without coordinated gaze 2 = Placement of another person’s hand or other body part on object 8 = Little or no spontaneous communication

Figure 4

ADOS Item B7 “Requesting” scores by cluster 0 = Points with index finger using coordinated gaze to object and person 1 = Using pointing to reference objects, without sufficient flexibility or frequency for ‘0’ 2 = Points to objects when close to or touching object, no coordinated eye gaze or vocalization 3 = Does not point to objects in any way

Figure 5

ADOS item C1 “Functional Play with Objects” scores by cluster 0 = Spontaneously and appropriately plays with variety of toys 1 = Some spontaneous functional play with cause-and-effect toys with at least 1 miniature 2 = Plays appropriately with cause-and-effect toys only, and/or pushing car 3 = No play with toys or only stereotyped play

Figure 6

ADOS item D4 “Unusually Repetitive Interests or Stereotyped Behaviors” scores by cluster 0 = No repetitive or stereotyped behaviors during the ADOS evaluation 1 = An interest or behavior that is repetitive or stereotyped to an unusual degree 2 = Repetitive or stereotyped interests and/or behaviors are minority of child’s interests or behaviors 3 =Repetitive or stereotyped interests and/or behaviors form majority of child’s interests

Figure 7

Diagnosis at age four by cluster