[monocle]

Statistics are statistics. There are numerous studies which show a higher risk as parent's ages increase. These studies do not attempt to explain why but only that the risk increases. Most would agree that smoking increases the risk of lung cancer but not every smoker gets lung cancer and people who have never smoked get lung cancer. The statistics demonstrate the risk and not the cause.

[Tax-chick]

The statistics on autism do not distinguish - can’t distinguish - between real-incidence and identification, and therefore, while what you say about “risk” is accurate if you define “risk” the way you are, the statistics are not necessarily helpful in drawing any conclusions.