Efficacy of Yale observation scale to detect serious bacterial infection in febrile children aged one to 36 months


  • Prerana Kansakar Patan Academy of Health Sciences
  • Prakash Sundar Shrestha
  • Merina Shrestha


Introductions: In most children aged 1-36 months, the cause of a febrile illness
is a self limiting viral infection. It is very difficult to distinguish these from
serious bacterial infection. Objective of this study is to assess the efficacy of
the Yale Observation Scale (YOS) to detect serious bacterial infection in febrile
children aged 1-36 months.

Methods: YOS scores were assigned as a part of a cross- sectional study in
100 children presenting in Tribhuvan University teaching hospital with fever to
divide the child into well- looking if YOS ≤10 or ill- looking if YOS >10. Then the history, examination and necessary investigation was performed to come to a diagnosis of non- serious illness and serious bacterial infection.

Results: Serious bacterial infection was found in 33(33%) of the patients. The
sensitivity, specificity, positive and negative predictive values for a YOS score
greater than 10 to detect serious bacterial infection were 45.45%, 88.05%%,
65.21% and 76.62%, respectively.

Conclusions: A YOS ≤10 predicts non-serious illness while a YOS>10 does not
necessarily indicate serious bacterial infection and should undergo further
evaluation to confirm serious bacterial infection.

Keywords: febrile children, serious bacterial infection, yale observation scale