Addressing common problems in autism research: cohort development and sample description for a participatory, real-world, longitudinal study of outcomes in autistic adults

Adult autism services research is plagued by methodological challenges, including difficulty obtaining representative or heterogeneous samples and a frequent mismatch between experimental methodologies and real-world settings. The Academic Autism Spectrum Partnership in Research and Education (AASPIRE) Outcomes Project used a community-based participatory research (CBPR) approach to (a) create the AASPIRE Measurement Toolkit – a set of self- and caregiver-reported accessible outcome measures to evaluate health and social services and (b) explore factors predicting changes in outcomes. We previously used a CBPR-nested Delphi process to identify high-priority outcomes and adapted or created instruments to measure them. We conducted a longitudinal survey to validate these measures in a pragmatic sample of autistic adults with subcohorts from two health care systems, two disability service systems, and the larger autistic community in the United States. This article (a) describes our study methods and the sample’s baseline characteristics and (b) compares characteristics among participants in the separate subcohorts and sites. We collected baseline data from 870 participants. Follow-up response rates were >80% for the second and third time points. The sample includes strong heterogeneity. As expected, sample characteristics differed markedly between the three subcohorts. Lessons from our experience may help other researchers devise strategies to effectively recruit heterogeneous samples of autistic adults across various settings.