Cognitive bias is a self-deceptive practice in which a person (unintentionally) selects data to support his or her hypothesis. Understanding this principle is central to the critical analysis of scientific research. Is the person influenced by what they are seeing (due to their position, etc) when seeing a subset of the universe? Is the person drawing conclusions, abstracting from the subset to the whole, without realizing that the subset is not a representative one?
There are many issues for concern when reviewing this article. First, Dr. Evans is embedded in a nonrepresentative world, is seeing two changes (increased cellphone use and increased identification of issues within children), and is stating a correlation on factors that may well be coincident. Second, there is the issue of the definition of mental illness in children. For autism (a general example, not one of mental illness), the definition and boundaries have shifted over time. This has been one of the causes of the increased incidence of autism. I will hypothesize that the definitions and boundaries of "mental illness" in children has also changed over time, and this may well be a critical factor in the increased incidence of the same.
Dr. Evans proposes an interesting hypothesis (and one we have heard before). But the evidence quoted in the article is circumstantial at best, consisting of anecdotes. She does not quote any general studies. She focuses solely on the negative aspects of a changing environment, without quoting on the positive. Without baselining the definition of "mental illness", without a complete and neutral analysis of the overall impact of the *change* (both positive and negative), Dr. Evans's proposal is at best a weakly supported hypothesis.