How non-autistic people think about autistic people impacts autistic people negatively. Many studies developed trainings to reduce autism stigma. The existing trainings vary a lot in terms of study design, content, and reported effectiveness. This means that a review studying how the studies have been conducted is needed. We also looked at the quality of these studies. We collected and studied 26 studies that tried to reduce stigma toward autistic people. The studies often targeted White K-12 students and college students. Most trainings were implemented once. Trainings frequently used video or computer. Especially, recent studies tended to use online platforms. The study quality was poor for most studies. Some studies made inaccurate claims about the intervention effectiveness. Studies did not sufficiently address study limitations. Future trainings should aim to figure out why and how interventions work. How intervention changes people’s behavior and thoughts should be studied. Researchers should study whether the training can change the societal stigma. Also, researchers should use a better study design.
Most interventions have focused on elementary/middle school students or undergraduate students and have been conducted in Western countries with primarily White participants. Researchers have frequently utilized computers or videos to implement interventions, and recent interventions tended to utilize online platforms. Interventions frequently included explanatory and descriptive information about autism and assessed stigma with self-reports. However, researchers often neglected to utilize robust interventions such as examining baseline and controlling for baseline characteristics and using and clearly describing randomization and blinding procedures. Finally, more than half of NRSIs made unwarranted, causal claims about the intervention’s effectiveness, and most interventions did not contextualize their findings, given the heightened risk of bias inherent in their studies. Based on our findings, we suggest the need for more interventions as follows:
1.Utilize robust designs considering all risk of bias domains;
2.Assess non-autistic participants’ attitudinal and behavioral short-term and long-term changes, using masked and reliable outcome variables;
3.Target clinicians and other professionals whose attitudes and beliefs about autistic people may become deeply engrained and can directly impact access to care;
4.Assess autistic people’s perceptions of the impact of interventions on stigma;
5.Conduct interventions targeting more diverse participant samples in various cultures, especially those who have not frequently been included in the anti-stigma intervention research so far such as older populations and racial/ethnic minorities;
6.Sufficiently contextualize findings given flaws in study designs;
7.Conduct moderator and mediator analyses to identify active ingredients of interventions for specific participant samples;
8.Reach the general public, community members, and stakeholders by developing targeted interventions that seek to spark societal changes in stigma.