Date: April 17th, 2019

Reference: Little et al. Major trauma: Does weekend attendance increase 30-day mortality? Injury 2019

Guest Skeptic: Alison Armstrong is a Certified Emergency Nurse, Trauma Program Coordinator and TNCC Course Director.

This was a special episode of the SGEM done live at the Talk Trauma 2019 Conference help in London, Ontario. Talk Trauma is a two-day conference for nurses, allied health and EMS professionals involved in providing care for the adult and paediatric trauma patient. Our philosophy for Talk Trauma is to have fun while learning so we put on a conference packed with useful tips for all trauma care providers but in a really fun way! It attracts participants from all over Ontario and even the US.

To get the crowd warmed up for our nerdy structured critical appraisal we reviewed a paper by Dr. Esther Choo et al. The article was called A lexicon for gender bias in academia and medicine: Mansplaining is the tip of the iceberg”. It was published in the December 2018 edition of the BMJ. 

Theme music is an important part of the SGEM. Alison picked the song It’s A Man’s World  by James Brown for this paper on gender bias in academia and medicine.

Mansplaining is defined as explaining something in a condescending or patronizing way, typically to a woman.

Alison picked out five of her favourite terms from the BMJ publication and presented them to the audience. This included: misteria, himpediment, hystereotyping, mutehism, and bromoteher. As a rural physician, I added one more term to the medical lexicon called “urbansplaining”

You can down load a copy of the slides, watch the presentation on the SGEM Facebook page and get a PDF copy of Dr. Choo’s article. 

Case: A 52-year-old man presents to the emergency department via EMS after a motor vehicle collision while driving home from the city. It is 2am Saturday morning and the night shift has been busy. You suspect he has been drinking. He has a Glasgow Coma Scale (GCS) score of 13 and an Injury Severity Score (ISS) of 19. There is small frontal head laceration. He is complaining of some right sided chest wall pain and shortness of breath.  There is an obvious knee injury. While he is waiting to get imaging and laboratory tests done, he asks if he will be more likely to die because it’s a weekend?

Background: We have busted many myths on the SGEM over the years. This have included the following medical myths:

  • Myth: Epinephrine saves lives with good neurologic outcome in OHCA (SGEM#64 and SGEM#238)
  • Myth: All buckle and greenstick fractures should be casted (SGEM#19)
  • Myth: A vitamin C cocktail can cure sepsis based on an observational study (SGEM#173)
  • Myth: Ketorolac 30mg IV is better than 10mg or 15mg IV for pain control (SGEM#174)
  • Myth: OHCA patients need an endotracheal airway (SGEM#247)

There are many other myths in medicine like that of the full moon effect (lunar effect). One large area of controversy is that of the “weekend effect”. This urban legend is that mortality rates go up when patients are admitted on the weekend vs. the weekdays.

Clinical Question: Does the “weekend effect” exist (increased mortality) in a UK trauma centre?

Reference: Little et al. Major trauma: Does weekend attendance increase 30-day mortality? Injury 2019

  • Population: Trauma patients presenting to the emergency department defined as Injury Severity Score greater than eight admitted between 2013 – 2015.
  • Intervention: None
  • Comparison: Weekday (Monday 00:00 to Friday 23:59) vs. weekend (Saturday 00:00 – Sunday 23:59).
  • Outcome:
    • Primary Outcome: Mortality by 30 days
    • Secondary Outcomes: Age, Glasgow Coma Scale (GCS), Injury Severity Score (ISS), mortality by days of the week, and mortality by 30 days on Friday 00:00 to Saturday 23:59 vs. Sunday 00:00 to Thursday 23:59.

Authors’ Conclusions“There is no significant difference in 30-day mortality when directly comparing weekday to weekend attendances. There is a significantly higher mortality on Friday and Saturday compared to remainder of the week which appears to be explained by a greater severity of head trauma.”

Quality Checklist for Observational Study:

  1. Did the study address a clearly focused issue? Yes
  2. Did the authors use an appropriate method to answer their question? Yes
  3. Was the cohort recruited in an acceptable way? Yes
  4. Was the exposure accurately measured to minimize bias? Yes
  5. Was the outcome accurately measured to minimize bias? Yes
  6. Have the authors identified all-important confounding factors? Unsure
  7. Was the follow up of subjects complete enough? Yes
  8. How precise are the results and the estimate of risk?  The 95% confidence intervals were fairly tight around the estimate of risk. They might be improved slightly by increasing the sample size, but they might also widen if validation is done in varying geographic areas and healthcare systems.
  9. Do you believe the results? Yes
  10. Can the results be applied to the local population?  Unsure
  11. Do the results of this study fit with other available evidence? Unsure

Key Results: They identified 1,424 patients in their Trauma Audit and Research Network (TARN) database. The mean age was 52 years, two-thirds were male patients and the mean Injury Severity Score was 19. One-third of patients were admitted on the weekend and two-thirds were admitted on the weekdays.

No difference in 30-day mortality between weekend (7.8%) and weekdays 7.7%).

  • Primary Outcome: 30-day mortality
    • Odds Ratio of mortality in the weekend group compared to the weekday group was 1.01 (95% CI 0.67–1.54)
    • Relative Risk of death in the weekday group compared to the weekend group was 0.987 (95% CI 0.671–1.451)
  • Secondary Outcomes:
    • Age: There was no significant difference in age between the two groups. However, the mean age of patients who died within 30 days was significantly greater than those who survived (70.8 vs 50.9 years, p < 0.0001)
    • Glasgow Coma Scale (GCS) Score: No significant difference when comparing different days of the week. However, patients who attend on a Friday or Saturday have a tendency to have more significant head injuries, as indicated by a lower average GCS, and were more likely to die from these.
    • Injury Severity Score (ISS): No significant difference in the ISS when comparing different days of the week.
    • 30-day Mortality by Day of the Week: It was highest in patients attending on Fridays (10.8%) and lowest in those attending on Sundays (5.5%).
    • 30-days Mortality Friday or Saturday: The relative risk was 1.584 (95% CI 1.102–2.278)

1) GCS and ISS: There is some subjectivity to both the GSC and the ISS. This can lead to a lack of inter-rater reliability of the GCS (Reith et al 2016) and the ISS (Ringdal et al 2013). The subjectivity and lack of inter-rather reliability of these scores could impact their accuracy. It is unclear if this would influence the direction or precision of the results.

2) Age: They did not specifically state these were adult patients. Including pediatric patients could change the results and the interpretation.

They did include geriatric patients, if you define that as 65 years and older. Older adults with blunt trauma and normal vital signs tend to be under triaged but have higher mortality despite the same ISS (Heffernan et al. J Trauma 2010). This is thought to be due to higher incidence of head injuries.

Older patients could skew the results. Especially since the inclusion criteria was ISS>8. These authors observed an association between increase in age and increase in mortality. It would have been interesting to see what the dataset looked like for those with an ISS of 8 or less. Also, do a specific test for mortality in all those over the age of 65 that the trauma team was activated.

3) Staffing: The same staffing levels, imaging resources and the ability to perform intervention did not vary according to the day of the week at this trauma centre. It is unclear if these results could be applied to other systems where staffing level is different on the weekend compared to weekdays.

4) External Validity: This was a single trauma centre in the UK. It is unsure if these results would be replicated in different trauma centres, in different countries with different healthcare systems.

5) Define Weekend: They defined weekend as Saturday and Sunday and did not find a “weekend effect”. However, when they defined a weekend as Friday and Saturday they did find a difference compared to Sunday through Thursday. This seemed to be more related to lower GCS and increased head injuries on Friday and Saturdays and not related to staffing.

Comment on Authors’ Conclusion Compared to SGEM Conclusion: We generally agree with the authors’ conclusions.

SGEM Bottom Line: It is still unknown if the “weekend effect” exists in trauma centres and it also depends on how you define weekend.

Case Resolution: The trauma team at LHSC is activated, they assess and identify all his injuries and he is admitted to hospital.  He is found to have a tibial plateau fracture, a couple non-displaced rib fractures, a hemopneumothorax and a head laceration. After a four day stay, he is transferred from the trauma centre to his home community hospital outside the city for on-going rehabilitation of his knee.

Alison Armstrong RN

Clinical Application: It is unclear how we can apply this information clinically. It would be a great research project to find out if there is a “weekend effect” in Ontario’s trauma centers.

What Do I Tell My Patient? We have a great trauma team and we will take great care of you. There is no evidence that more trauma patients are more likely to die in a health care system like ours on the weekend compared to the weekdays.

Keener Kontest: Last weeks’ winner was Harrison Pidgeon a 4th year medical student in incoming EM intern at Rush University Medical Centre. He knew the female physician suicide rate is 2.27 times that of the general female population.

Listen to the podcast to hear this weeks’ trivia question. If you know the answer, send an email to with “keener” in the subject line. The first correct answer will receive a cool skeptical prize.

Remember to be skeptical of anything you learn, even if you heard it on the Skeptics’ Guide to Emergency Medicine.