The study stated that one child saw an almost complete amelioration of autistic symptoms.
The study mentions that the other five showed improvement but that it could have been just the placebo effect. If someone were to recover that would be obvious. Having it double blinded or having a large sample would not be necessary if the change was obvious. The study did not state that no further research should be done. They said caution should be used as only a very small fraction of a fraction of people with autism may be benefited by the treatment and the cost of the treatment would be very high.
I am not sure why if indeed the one child showed "a very significant amelioration of autistic symptoms" the parents did not wish to continue the research. Maybe the cost of the treatment was millions or something. I still believe it though.
Here is the text if the link doesn't work:
"Since autism has been associated with immunologic abnormalities suggesting an autoimmune cause of autistic symptoms in a subset of patients, this study was undertaken to investigate whether intravenous immunoglobulin (i.v.Ig) would improve autistic symptoms. Ten autistic children with immunologic abnormalities, demonstrated on blood tests, were enrolled in this study. Their ages ranged from 4 to 17 years, with two girls and eight boys. Eight children (1 female and 7 male) historically had undergone autistic regression. Intravenous immunoglobulin, 200 to 400 mg/kg, was administered every 6 weeks for an intended treatment program of four infusions. In five children, there was no detectable change in behavior during the treatment program. In four children, there was a mild improvement noted in attention span and hyperactivity. In none of these children did the parents feel that the improvement was sufficient to warrant further continuation of the infusions beyond the termination of the program. Only in one child was there a very significant improvement, with almost total amelioration of autistic symptoms over the time period of the four infusions. Once the treatment program was completed, this child gradually deteriorated over a 5-month time period and fully reverted to his previous autistic state. In this treatment program, five children had no response to intravenous immunoglobulin. In the four children who showed mild improvements, those improvements may simply have been due to nonspecific effects of physician intervention and parental expectation (ie, placebo effect). However, in one child there was a very significant amelioration of autistic symptoms. There were no distinguishing historic or laboratory features in this child who improved. Given a positive response rate of only 10% in this study, along with the high economic costs of the immunologic evaluations and the intravenous immunoglobulin treatments, the use of intravenous immunoglobulin to treat autistic children should be undertaken only with great caution, and only under formal research protocols."