Table 1.

Themes and examples of illustrative #NotMssng Tweets.

Theme	Corresponding Tweets
Internalization of autism as part of self-identity.	“I am Autistic and I am #NotMssng! I am right here and I can speak for myself”
Representation of a collective autistic identity.	“We are here, We are healthy, We are intelligent, We are #NotMssng. Please listen to us for once Autism Speaks instead of hurting us!”
MSSNG interpreted to mean autistic people are missing or are missing something.	“Disability is a natural part of the human condition. We are #NotMssng, we are not less than, & not #Mssng our humanity.”
Autistic people are missing from the conversation.	“How appropriate they chose the letter I. I am Autistic, but when Autism Speaks is involved, I am #mssng from the conversation. #NotMssng”
Support and services for autistic people are what is missing.	“I am not autistic, but the autistic people in my life are #NotMssng. What IS ‘mssng’ is support and respect for autistic people.”
	“How about research into supports and services instead of elimination and cure? #NotMssng #Mssng @autselfadvocacy”
Attempts to develop a cure for autism are equivalent to attempts to eliminate people with autism.	“@autismspeaks Autism has no cure because it is hard-wired in the brain. If you eradicate autism, you eradicate autistic people. #NotMssng”

We consulted with the Baylor College of Medicine Institutional Review Board (IRB), and the IRB confirmed that the use of Twitter data is exempt from human subject research oversight under 45 CFR 46.102(f) (under the version of the Common Rule that took effect July 19, 2018, 46.102(e)).