A randomized controlled trial evaluating the effects of nurse-led triage of 911 calls

Abstract

To better connect non-emergent 911 callers to appropriate care, Washington, DC, routed low-acuity callers to nurses. Nurses could provide non-emergent transportation to a health centre, recommend self-care or return callers to the traditional 911 system. Over about one year, 6,053 callers were randomized (1:1) to receive a business-as-usual response (n_control = 3,023) or further triage (n_treatment = 3,030). We report on seven of nine outcomes, which were pre-registered ( https://osf.io/xderw ). The proportion of calls resulting in an ambulance dispatch dropped from 97% to 56% (β = -1.216 (-1.324, -1.108), P < 0.001), and those resulting in an ambulance transport dropped from 73% to 45% (β = -3.376 (-3.615, -3.137), P < 0.001). Among those callers who were Medicaid beneficiaries, within 24 hours, the proportion of calls resulting in an emergency department visit for issues classified as non-emergent or primary care physician (PCP) treatable dropped from 29.5% to 25.1% (β = -0.230 (-0.391, -0.069), P < 0.001), and the proportion resulting in the caller visiting a PCP rose from 2.5% to 8.2% (β = 1.252 (0.889, 1.615), P < 0.001). Over the longer time span of six months, we failed to detect evidence of impacts on emergency department visits, PCP visits or Medicaid expenditures. From a safety perspective, 13 callers randomized to treatment were eventually diagnosed with a time-sensitive illness, all of whom were quickly triaged to an ambulance response. These short-term effects suggest that nurse-led triage of non-emergent calls can safely connect callers to more appropriate, timely care.