Use of ED Diagnosis to Determine Medical Necessity of EMS Transports

Abstract

Objective. To examine interrater agreement for classifying emergency medical services transports as medically unnecessary using emergency department diagnosis as the sole determining factor. Methods. Three emergency physicians andtwo family medicine physicians classified 913 International Classification of Diseases, Ninth Revision (ICD-9) codes as medically necessary, unnecessary, or uncertain. Overall agreement, interrater agreement, andagreement within 17 major disease categories were measured using κ statistics in SAS. Results. Physicians rated between 25% and65% of diagnoses codes as medically unnecessary. Overall agreement was fair (κ = 0.31). Agreement within specialties was higher among family medicine–trained physicians than among emergency physicians (κ = 0.52 andκ = 0.22, respectively). Agreement across all raters was highest for diseases classified as symptoms, signs, andill-defined conditions (κ = 0.40) andlowest for diseases of the blood andblood-forming organs (κ = −0.17). Agreement was observably better between physicians with more experience. Conclusions. Considerable doubts about the utility of emergency department diagnosis as a criterion are raised from study findings. Further development of Neely Conference criteria is needed. Priority should be given to testing andvalidation of criteria as well as exploration of differences in judgment between specialists representative of the medical director profession.