2008 ICD-9-CM Volume 1 Diagnosis Codes Home > Mental Disorders 290-319 > Mental Retardation 317-319 > Other Specified Mental Retardation 318.* > 2008 ICD-9-CM Diagnosis 318.0 Moderate mental retardation  On October 1, 2008 the 2009 ICD-9-CM codes came into effect. Therefore, this code may be out of date. The 2009 version of ICD-9-CM 318.0 can be accessed here. 318.0 is a specific code that can be used to specify a diagnosis 318.0 contains 6 index entries View the ICD-9-CM Volume 1 318.* hierarchy ICD9Data's sister site ProcedureCodes.com launches with the 2008/09 CPT® codes - read more on the ICD9Data.com blog. 318.0 also known as: IQ 35-49 Moderate mental subnormality Index entries containing 318.0: Imbecile, imbecility 318.0 moral 301.7 old age 290.9 senile 290.9 specified IQ - see IQ unspecified IQ 318.0 IQ 35-49 318.0 Mental - see also condition subnormality (see also Retardation, mental) 319 moderate 318.0 Retardation mental 319 moderate, IQ 35-49 318.0 Subnormal, subnormality mental (see also Retardation, mental) 319 moderate 318.0