ICD-9-CM classification coding in psychiatry.

The question was addressed how well mental health professionals were able to translate diagnostic formulations into ICD-9-CM codes. This was done with three coder groups and under two conditions. It was found that there was insufficient interrater agreement on the ICD-codes in all groups and conditions. This finding then was related to the inadequacies of the ICD-system itself. It was concluded that current mental health statistics that are based on the ICD-9-CM coding system are without scientific value.