Behavioural nudges to reduce low-value care for low back pain in the emergency department (NUDG-ED): a 2 × 2 factorial, pragmatic cluster randomized trial

Clinical Snapshot

Key Findings

• P Value: Not significant for either intervention (p-values not reported in abstract)

• Effect Size: Patient nudges: 36.4% vs 38.1% (5.2% absolute reduction); Clinician nudges: 39.4% vs 35.0% (4.4% absolute increase)

• Primary Outcome: Proportion of encounters with low-value care (non-indicated imaging or opioid prescription)

• Nnt Or Sensitivity: No significant benefit demonstrated; NNT cannot be calculated due to non-significant results

• Confidence Interval: Patient nudges OR 0.80 (95% CI 0.51-1.27); Clinician nudges OR 1.31 (95% CI 0.84-2.05)

Clinical Application

Interventions appear feasible (electronic posters and EHR alerts) but effectiveness not demonstrated Directly applicable to Australian EDs; aligns with efforts to reduce low-value care but results suggest these specific nudge interventions are ineffective Emergency department patients presenting with low back pain in Australian healthcare settings

Abstract

BACKGROUND: Low-value care exposes patients to unnecessary risk and wastes scarce health resources. We aimed to determine if patient- or clinician-directed nudges could reduce low-value care for low back pain in the emergency department. METHODS: We conducted a 2 × 2 factorial, cluster randomized controlled trial involving patients with low back pain presenting to emergency departments. Eight emergency departments were randomized to receive patient nudges (6 electronic information posters discouraging unnecessary imaging and opioids, displayed on 55-inch screens in waiting rooms), clinician nudges (3 electronic health record alerts that provided indications for lumbar spine imaging and suggested alternatives to opioids), both patient and clinician nudges, or no nudges. The primary outcome was the proportion of encounters for low back pain with low-value care, defined as non-indicated lumbar spine imaging test, opioid prescription at discharge, or both. We calculated odds ratios (ORs), adjusted for baseline and clustering. RESULTS: There were 3770 encounters for low back pain during the study period. The overall baseline prevalence of low-value care was 41.6%. During the intervention period, the proportion of encounters with low-value care reduced to 36.4% with patient nudges versus 38.1% without, but the difference was not significant (adjusted OR 0.80, 95% confidence interval [CI] 0.51 to 1.27). The proportion of encounters with low-value care was 39.4% with clinician nudges versus 35.0% without (adjusted OR 1.31, 95% CI 0.84 to 2.05). We did not observe an interaction effect between the interventions (p = 0.4). The patient nudge may have reduced strong beliefs among patients in the value of imaging for low back pain. We found no important differences in secondary outcomes. INTERPRETATION: Nudges - including waiting room information posters targeting patients and electronic health record alerts targeting clinicians - did not reduce low-value care in emergency departments. TRIAL REGISTRATION: www.anzctr.org.au, ACTRN12623001000695.

References

1. 1.Altinger, G., Sharma, S., Maher, C. G., Cullen, L., McCaffery, K., Linder, J. A., Buchbinder, R., Harris, I. A., Coiera, E., Li, Q., Devaux, A., Howard, K., Coggins, A., Middleton, P. M., Gunja, N., Ferguson, I., Chan, T., Mallows, J., Darby, S., Tambree, K., van Wyk, A., & Traeger, A. C. (2026). Behavioural nudges to reduce low-value care for low back pain in the emergency department (NUDG-ED): a 2 × 2 factorial, pragmatic cluster randomized trial. CMAJ, 198(13), E456-E465. https://doi.org/10.1503/cmaj.251595