Background and purpose: Accurate prehospital diagnosis of acute stroke may lead to fewer delays in hospital presentation. In addition, prehospital personnel soon may be administering therapies to patients with presumed stroke. We sought to determine the sensitivity and positive predictive value (PPV) of paramedic diagnosis of stroke in Mobile, Alabama, and to evaluate the impact of an educational program on paramedic diagnostic capability.
Methods: We collected data from all paramedic-diagnosed stroke patients transported to a University of South Alabama hospital by Mobile Fire Medics. Final diagnosis was determined by a neurologist and classified as stroke or nonstroke (i.e., PPV). Paramedic diagnoses for all hospitalized stroke patients transported by Mobile Fire Medics were also reviewed (i.e., sensitivity). Sensitivity and PPV were calculated for the period 6/13/95 to 3/13/97. In addition, both indices were calculated for the period before (6/13/95 to 5/5/96) and after (6/25/96 to 3/13/97) an 8-week intensive educational program.
Results: Seventy-one hospitalized stroke patients were transported by Mobile Fire Medics during the study period. Paramedics correctly identified 67 patients in total (94% sensitivity), 29 during the pre-education period (91% sensitivity), and 29 during the posteducation period (97% sensitivity; P=.33). Twenty-five patients were incorrectly diagnosed with stroke (73% PPV), 15 during the pre-education period (66% PPV), and 9 during the posteducation period (76% PPV; P=.30).
Conclusion: Although paramedics in Mobile misdiagnose few patients with acute stroke, there is a tendency toward overdiagnosis. An educational intervention resulted in a trend toward improved accuracy of diagnosis, but this did not reach statistical significance.