Many childhood disorders have associated conditions that we need to be on the lookout for.  Children's neuro-psychological profiles can change during the course of childhood and diagnoses made during the early years may either not hold up in later years or be joined by new diagnoses.  Comorbidity is when diagnoses overlap or co-exist.  For example, ADD/ADHD very often exists along side other disorders, such as dyslexia or PDD-NOS and other spectrum disorders.  Or, ADHD and Anxiety Disorder frequently occur in the same individual.  Unfortunately, comorbidity seems to be more the rule than the exception. 

If your child has a specific diagnosis, "the comorbidity principle" suggests that other conditions may be waiting to be diagnosed.  Puzzling symptoms or treatments that don't seem to be as effective as they should be may be the clues to an associated condition.  The child's neuro-psychological and medical profile can take many months or years to fully observe and define. 

Educational therapists are particularly attuned to the possibility of comorbidity and help parents and teachers sort out the symptoms and behaviors in order to ensure appropriate referrals for assessment.

*Packer, L.E. and Pruitt, S.K. Challenging Kids, Challenged Teachers, Woodbine House, 2010.