The effect of triage-applied Ottawa Ankle Rules on the length of stay in a Canadian urgent care department: a randomized controlled trial

Acad Emerg Med. 2006 Feb;13(2):153-7. doi: 10.1197/j.aem.2005.07.041. Epub 2006 Jan 25.


Objectives: To determine whether triage nurses ordering ankle or foot radiographs according to the Ottawa Ankle Rules (OAR) before physician evaluation decreases the length of stay for patients visiting an urgent care department.

Methods: From July to September 2004, a randomized controlled trial of consecutive adult patients with ankle or foot twisting injuries who arrived at an urgent care department was conducted. Patients were included if their age was 18 years or older and their injury had occurred within seven days. They were excluded if there were neurovascular deficits, limb deformities, open fractures, or nonisolated ankle or foot injuries. Patients were randomly allocated to a roentgenogram-ordering clinical pathway (intervention) or to standard departmental care (control). Those assigned to the intervention group had triage nurses applying the OAR, and those with positive OAR were sent for roentgenograms before physician evaluation. Physicians were blinded to negative OAR nurse assessments. Investigators were blinded to group allocation. The primary outcome was the total mean length of stay (TLOS). The secondary outcomes were patient satisfaction (five-point ordinal scale) and the proportion willing to return to the site for future care. Two-independent sample t-test was used to analyze the TLOS. The Kruskal-Wallis test was used to analyze satisfaction ratings differences between groups. Fisher's exact test was used to analyze the willing-to-return outcome. This study had 80% power to detect an effect size of 25 minutes.

Results: Two hundred thirty-two patients were eligible; 130 patients gave consent and were enrolled. Three patients were then excluded, three were lost to follow-up, and one left without being seen. The intervention and control groups had mean TLOS of 73.0 minutes and 79.7 minutes, respectively. There was a statistically nonsignificant time difference of -6.7 minutes (95% CI = -20.9 to 7.4) between groups. There were no differences in patient satisfaction ratings (p-value = 0.343) or WOR (3.8%; 95% CI = -3.3% to 11.0%).

Conclusions: The use of OAR and the ordering of roentgenograms by triage nurses before physician evaluation for twisting ankle or foot injuries does not decrease the length of stay in an urgent care department.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Ankle Injuries / diagnostic imaging*
  • Emergency Service, Hospital / organization & administration*
  • Female
  • Foot Injuries / diagnostic imaging*
  • Humans
  • Length of Stay*
  • Male
  • Middle Aged
  • Ontario
  • Patient Satisfaction
  • Prospective Studies
  • Radiography
  • Triage*