A Tale of Two Disability Coding Systems: The Veterans Administration Schedule for Rating Disabilities (VASRD) vs. Diagnostic Coding Using the International Classification of Diseases, 9th Edition, Clinical Modification (ICD-9-CM)

Disability rates have increased by approximately 10 per year over the past 25 years. Little is known about the etiology, in part because Veterans Administration Schedule for Rating Disabilities VASRD codes are not clinical diagnoses. This report describes results from analyses linking VASRD disability codes to International Classification of Disease, 9th Rev., Clinical Modification ICD-9-CM clinical diagnoses captured in hospital administrative records during disability case processing. Results suggest that while the primary ICD-9-CM codes generally correspond logically to VASRD codes in the associated disability discharge records, some VASRD categories lack homogeneity, substantially reducing their value for research and surveillance purposes. Infectious disease, immune disorder, or nutritional deficiency hemic and lymphatic systems and gynecological conditions and disorders of the breast are either extensively heterogeneous or lack specificity which may result in only partial capture of cases with the same etiology in that particular VASRD group e.g., breast disorders may logically be placed in more than one VASRD category. Primary clinical conditions experienced by soldiers discharged with musculoskeletal disabilities, the most common VASRD disability group, were pain in joint, lumbago, joint derangement, chondromalacia patellae, and osteoarthrosis--all diseases of the musculoskeletal system and connective tissue ICD-9-CM 710-739. Overall concordance between ICD-9-CM clinical conditions and VASRD codes for musculoskeletal disability suggest good face validity. All ICD-9-CM diagnoses associated with the two major VASRD subgroups within musculoskeletal disability--Injury or Disease--fall within the ICD-9-CM 710-739 group suggesting there may be little clinical value in differentiating between Injury vs. Disease.