Developing Korean Academy of Medical Sciences guideline for rating the impairment in mental and behavioural disorders; a comparative study of KNPA's new guidelines and AMA's 6th Guides

I refer to the paper by Ryu, Hong, Jung, Hwang, Jung, Jeong, Rah and Suh (2009) (1). The assessment of psychiatric disability is difficult and fraught with methodological problems and the review by Ryu and colleagues tends to perpetuate the use of methods of assessment which have no firm evidence base as well as ignoring some significant problems with the use of the American Medical Association Guides as well as the Psychiatric Impairment Rating Scale (PIRS).