Alternative therapies for developmental and learning disabilities include a range of practices used in the treatment of dyslexia, ADHD, autism spectrum disorders, Down syndrome and other developmental and learning disabilities. Treatments include changes in diet, dietary supplements, biofeedback, chelation therapy, homeopathy, massage and yoga. These therapies generally rely on theories that have little scientific basis, lacking well-controlled, large, randomized trials to demonstrate safety and efficacy; small trials that have reported beneficial effects can be generally explained by the ordinary waxing and waning of the underlying conditions.