This Article  • Full text  • PDF  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citing articles on HighWire  • Citing articles on ISI (3)  • Contact me when this article is cited  Related Content  • Related article  • Similar articles in JAMA

	Since this article does not have an abstract, we have provided the first 150 words of the full text and any section headings.

To the Editor: Dr Dales and colleagues¹ reported that there was "essentially no correlation'' between rates of autism and measles-mumps-rubella (MMR) vaccine, but this conclusion is based on their Figure, which seems to be an optical illusion. We took the y-axis values directly from the Figure and computed the correlation coefficients, which are 0.73 and 0.90 between the total number of autism cases and the percentage of children receiving immunization by 24 months and 17 months, respectively. The illusion of no relationship is due to the vertically compressed graph. The apparent steepness of the autism curve may be attributed to the well-known epidemic effect of increased detection due to increasing vigilance.

Furthermore, their data show that the age of immunization was becoming younger between 1981 and 1993. In our Figure 1, we plot the ratio of children immunized before age 17 months with those immunized between age 17 and . . . [Full Text of this Article]

RELATED ARTICLE

Time Trends in Autism and in MMR Immunization Coverage in California
Loring Dales, Sandra Jo Hammer, and Natalie J. Smith
JAMA. 2001;285(9):1183-1185.
ABSTRACT | FULL TEXT  

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

Intestinal Pathophysiology in Autism
White
Exp. Biol. Med. 2003;228:639-649.
ABSTRACT | FULL TEXT  

A Population-Based Study of Measles, Mumps, and Rubella Vaccination and Autism
Madsen et al.
NEJM 2002;347:1477-1482.
ABSTRACT | FULL TEXT