Notifying emergency department patients of negative test results: pitfalls of passive communication

Many emergency departments that perform a high volume of group A Streptococcus throat cultures inform patients or parents that unless they are notified of a positive result they can assume that their throat culture result is negative. Thus, positive throat culture results are communicated actively and negative results are communicated passively. We sought to determine the effectiveness and safety of such a system.

Prospective cohort study of 301 consecutive patients who had group A Streptococcus throat cultures obtained between March 28, 2000, and May 10, 2000, in the emergency department of an urban, academic, tertiary-care children's hospital. Outcomes were determined by telephone surveys of patients or their parents or guardians. The primary outcome was whether respondents had accurate knowledge of the throat culture result. Secondary outcomes included receipt of appropriate treatment instructions, need for another telephone call to the emergency department or primary-care provider to clarify the result or treatment instructions, satisfaction with the communication process, and preference to receive both positive and negative results or just positive results.

Fifty-three percent of respondents did not have accurate knowledge of the throat culture result, 5% received inappropriate treatment instructions, 13% sought further clarification, 29% were dissatisfied with the communication process, and 85% preferred to receive both positive and negative results. Parents of patients with positive results were more likely to have accurate knowledge of the result (odds ratio 6.9, 95% confidence interval 1.4-65.7) and to be satisfied with the communication process.

Passive communication of negative throat culture results to patients seen in the emergency department can be unreliable. Active communication of both positive and negative results may improve patient knowledge and satisfaction and ensure appropriate therapy, but in the absence of automated notification systems, would be resource intensive.