The Stanford Social Motivation Scale: Preliminary Support for a Measure of Social Motivation in ASD

Background: It has been hypothesized that deficits in social motivation may play a significant contributory role in the social deficits of individuals with autism spectrum disorder (ASD; Dawson et al., 1998; Grelotti et al., 2002; Chevallier et al., 2012). Though some measures assess social motivation as a component of social functioning (such as the Social Responsiveness Scale [SRS-2; Constantino & Gruber, 2005] and Multidimensional Social Competence Scale [Yager & Iarocci, 2013]), there is currently no tool available to specifically measure the drive to engage socially.

Objectives: The current study aimed to create a valid measure of social motivation for individuals with ASD.

Methods: After extensive literature review and consultation with experts in the field, a 71-item questionnaire, the Stanford Social Motivation Scale (SSMS) was developed. The questionnaire includes four content areas derived from theoretical models of social domains: social drive, quality of overtures, behaviors that sustain an interaction, and social recognition. A 28-item subset was identified by experts as being extremely relevant to social motivation. The questionnaire was given to parents of children with ASD and typically developing (TD) controls to determine the validity of the measure. Other measures that included questions about social functioning, such as the SRS, were also collected in order to compare parents’ responses with the SSMS.

Results: To date, data have been collected from parents of 62 children with ASD and 14 TD controls. The majority of both groups were male and either Caucasian or Asian. There was a significant difference between the mean SSMS score between the ASD and TD groups (p < .001) for both the full 71-item scale and the 28-item scale. There was no significant difference in SSMS performance based on either IQ or age, suggesting that the measured behavior is independent of age or level of cognitive functioning. The 71-item scale was correlated with the 28-item SSMS (r = .942, p <.001), as well as each of the four content areas (range r = .997 to .563, p <.001). Amongst content scales, strong correlations were found between the 28-item scale and the social drive and behaviors that sustain an interaction scales (r = .997; r = .818). Moderate correlations were found for the quality of social interactions and social recognition scales (r = .688; r = .563). The total SSMS score was also highly correlated with the SRS-2 total T-score (r = .836; p <.001).

Conclusions: Preliminary findings show support for the SSMS as a valid means of characterizing social motivation in children with ASD. It also has the potential to provide a useful tool for measuring this construct across diagnoses, and has implications for phenotyping, treatment planning, and progress monitoring. Further psychometric analysis is currently underway, including the addition of psychiatric and developmental disability comparison groups, as well as a larger sample.