All psychiatrists and psychologists are not equally knowledgeable about everything, just as all plumbers are not equally skilled at all aspects of plumbing.
Multiple posts on Psychology Today have been criticizing the concept of childhood bipolar disorder, but (based on searching authors' names on www.pubmed.org) none have been written by anyone who has published even one MEDLINE-referenced scientific article on bipolar disorder.
In other words, everyone feels free to opine. I find that many of the comments on such blogs, made by families with children with bipolar disorder, show more expertise than the bloggers themselves.
Here is one example: It is constantly repeated that bipolar disorder is overdiagnosed because of an overhyped study which found that the bipolar diagnosis had increased in children 40-fold from the mid 1995 to 2003..
Obviously it's overdiagnosed, then, right?
Our non-experts don't seem to have read that study carefully; if they did, they could answer this question: What was the absolute rate of childhood bipolar disorder in 1995?
What is a 40-fold increase? 0.4%.
When you start from practically nothing, and then diagnose a fraction of one percent of children with a diagnosis - is that overdiagnosis?
What is the "true" rate of bipolar disorder in children? Based on our best epidemiological data, using standard DSM-IV criteria, the National Comorbidity Survey found that about 25% of all adult cases of bipolar disorder began before age 17, with 10% occuring before age 10. The lifetime rate was 5.1%. What's 10% of 5.1%?
So 0.5% of children and adolescents are diagnosable with bipolar disorder.
Now, is it overdiagnosis when 0.4% are diagnosed with a condition that occurs in 0.5% of the population?
This blogger strongly recommend's Dr. Kaplan's blog based on the faith that God and Nature allow 1.9% of 13 year-olds to have bipolar disorder (based on the National Comorbidity survey adolescent population epidemiological study), but zero percent of 12 year-olds. I wonder what day of the year it is in which the switch is suddenly allowed metaphysically? Readers can see my replies to this unscientific belief-system on that blog.