Monica L Bellon-Harn, Jianyuan Ni, Vinaya Manchaiah have an article at Autism titled "Twitter Usage about Autism Spectrum Disorder."
Stakeholders within autism spectrum disorder communities use Twitter for specific purposes. The goal of this study was to characterize patterns and themes of tweet content and sentiment and intercommunications between users sending and retweeting content to their respective user networks. The study used cross-sectional analysis of data generated from Twitter. Twitter content, sentiment, users, and community networks were examined from a sample of tweets with the highest Twitter reach and the lowest Twitter reach. Results indicate that Twitter content from both samples was primarily related to empowerment and support. Differences between the number of tweets originating from an individual in the lowest reach sample (i.e. 41%) as compared to the individuals in the highest reach sample (i.e. 18%) were noted. The number of users belonging to an advocacy subcommunity was substantially larger than a clinical and research subcommunity. Results provide insight into the presuppositions of individuals with autism spectrum disorder, their families and significant others, and other stakeholders.
From the article:
The second most frequently identified category from the highest reach sample emphasized the fact that vaccines do not cause autism. This content comprised the most tweets in a given hour on a given day. Please note that the >5000 and >3000 retweets were not excluded and could influence these results. Fewer tweets included misinformation about vaccines.A big limitation here: many antivax tweets do not use the autism or the other keywords employed in this study. They often link to material that propounds the discredited notion of a vaccine-autism link but the tweets themselves speak in more general terms, using terms such as "informed consent," "vaccine safety" or "vaccine choice." (See this post about "entryism.")