AnnalsEMCT imaging is a powerful tool in diagnosing pathological medical conditions. Despite this, there is appropriate concern about the “magnitude of imaging-related financial costs and radiation induced malignancies.” In this month’s Annals of Emergency Medicine journal publication, Berdachl et al published about “Emergency Department Computed Tomography Utilization in the United States and Canada.” This article was selected by the journal as the featured piece for a Journal Club discussion. In this inaugural global EM journal club, ALiEM and Annals are collaborating to provide a more dynamic discussion of some of the posed questions. The focus is on teaching concepts around HOW to critically appraise a journal article rather than just receive a pre-digested summary statement from social media sites and textbooks.

Annals Editor’s Capsule Summary

PDF of article
PDF of entire list of Annals journal club questions

  • What is already known on this topic: Recent studies have documented increasing use of computed tomography (CT) during the past decade in the United States.
  • What question this study addressed: Is there a difference in CT utilization in emergency departments (EDs) between the United States and Ontario, Canada?
  • What this study adds to our knowledge: In a retrospective comparison of data from the US National Hospital Ambulatory Medical Care Survey and all ED visits in Ontario, CT was used more frequently in US EDs versus those in Ontario. CT use increased in both jurisdictions over time, although CT use decreased among children younger than 10 years in Ontario.

Journal Club Questions

Each of these questions, posed by Drs. David Schriger, Michael Callaham, and Tyler Barrett, will be discussed on a separate blog post today to avoid crossing discussion threads. Click on the question below to take you to the appropriate discussion thread.

  1. Bias: The authors use distinct methods for tallying computed tomography (CT) use in the 2 countries. List the biases that could occur in counting CTs by each method.
  2. Estimation of CT Counts: Do you think the National Hospital Ambulatory Medical Care Survey (NHAMCS) method is likely to overcount or undercount CTs? What about the method used for calculating use in Ontario? Would these biases likely make the authors’ estimate of the overall difference between these countries too large or too small? Defend your answer.
  3. Malpractice and CT Use: Discuss some of the important differences between the current health care systems and medical malpractice environments in Canada and the United States. How might these differences affect CT use in the emergency department (ED)? How might the implementation of the Patient Protection and Affordable Care Act in the US affect these differences?
  4. Reimbursement Tied to Diagnosis: The Centers for Medicare & Medicaid Services (CMS) proposed instituting a new process metric OP 15 “Use of Brain CT in the Emergency Department of Atraumatic Headache.” OP 15 measures the percentage of ED visits for atraumatic headache (ie, ED billing codes for tension, cluster, migraine, and nonspecific headaches) among Medicare beneficiaries who have a brain CT performed on the same day. ED patients who are admitted to the hospital and those whose secondary diagnoses include codes related to subarachnoid hemorrhage, transient cerebral ischemia, and tumor/mass are excluded from the denominator. The public reporting of OP 15 is presently postponed to allow time for refinement of the measure by a technical expert panel. However, if this indicator is fully instituted, would the threat of decreased reimbursement and public reporting of use decrease your ordering of CTs in patients older than 65 years and with atraumatic headaches?
  5. Other Discussions: For all other comments that don’t fit into the above 4 sections, feel free to comment below.

Discussion closing date: Sunday, November 24, 2013 at 5 pm EST

All comments and tweets AFTER November 24 will not be curated into a summary piece for publication. We are considering quoting great comments and tweets in the publication. Maybe that will be YOU!

Instructions on how to participate in and follow the Twitter discussion

In order to avoid cognitive overload and overlapping Twitter discussion, only one journal club questiosn will be tweeted out per day. So these four questions will be tweeted out this week during Monday through Thursday. Be sure to add the hashtag #ALiEMJC so that we can all follow the discussion.

Instructions on how to comment

You can Sign In or Post as a Guest (don’t need password) as above. Your email is needed so that you are notified when someone replies to your comment. When done, hit the large, right-pointing Gray arrow.

  • Consider adding your training level/title(s) and where you are from in your comment so that we can all see the geographic and provider diversity.
  • Remember that you can add URL links and images to help enhance your discussion point. Let’s build a networked map of useful references.
  • Even if you have nothing to add, you can still hit the ^ button (it’s like a +1 vote) under any comment to vote-up in support.


Michelle Lin, MD
ALiEM Founder and CEO
Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco
Michelle Lin, MD


Professor of Emerg Med at UCSF-Zuckerberg SF General. ALiEM Founder @aliemteam #PostitPearls at Bio:
Michelle Lin, MD