Journal Club Summary

Methodology Score:    2.5/5                © Nevit Dilmen [CC BY-SA 3.0 ( or GFDL (], via Wikimedia Commons

Usefulness Score:  2.5/5 

Abrahamian FM, Krishnadasan A, Mower WR, et al.
Ann Emerg Med. 2013 Nov;62(5):526-33.
Pyuria alone cannot be used to determine if UTI is present in patients with acute nephrolithiasis. Pitfalls of this prospective observational study included convenience sampling, workup bias and lack of patient follow-up after ED discharge. Despite these limitations, considering this and other literature supporting the poor sensitivity and specificity of urinalysis, JC attendees agreed that a composite of pyuria, fever, female gender, and clinical gestalt should be used to help guide decision making for management and disposition of these patients. 
By: Dr. Carly Rogenstein
(Presented May 2015)

Epi Lesson: Spectrum bias

We tend to assume that a diagnostic test performs consistently among different populations but this may not be the case. The sensitivity and specificity of a given test may vary depending on factors such as sex, race and co-morbidities. Spectrum bias occurs when the assumption is made that the test is consistent across populations when in fact it is not. 
By: Dr. Lisa Calder