Best Evidence Topics


Baker R.C, Tiller T., Bausher J. et al
Severity of Disease correlated with fever reduction in febrile infants
Vol.83 no 6 June 1989; 1016 - 20
  • Submitted by:Marion Schmidt - Consultant Paediatrician
  • Institution:Royal Gwent Hospital , Newport
  • Date submitted:29th April 2005
Before CA, i rated this paper: 7/10
1 Objectives and hypotheses
1.1 Are the objectives of the study clearly stated?
  Yes :
Test the hypothesis that persistent clinical signs of illness despite fever reduction is a reliable sign of bacteraemia in febrile infants
2 Design
2.1 Is the study design suitable for the objectives?
  Yes : prospective cohort of all children(3 - 24 months) presenting to the emergency department of a children's hospital with a fever September 1986 to January 1988
2.2 Who / what was studied?
  Children between 3 to 24 months with temperature > 39.4 C
No antibiotics within preceding 48 hours
Children with overt signs of meningitis or septic shock were excluded as they required immediate treatment
All children were assessed using the Yale observation score (YOS) followed by full clinical examination by paediatric doctor on call.
All had a blood count , blood culture ,urine culture done; CXR and LP optional.
All children received Paracetamol 15 mg/kg, were undressed to nappy only.
All were reassessed by same observer who did the original Yale Observation Scale and temperature within the second hour following administration of paracetamol.
2.3 Was a control group used if appropriate?
  No control group but comparison of bacteramic children with non bacteraemic children within cohort
2.4 Were outcomes defined at the start of the study?
  Outcome : Improvement in clinical status as measured by YOS comparing bacteraemic versus non- bacteraemic children
Secondary outcomes : WCC, neutrophil count comparing bacteraemic versus non- bacteraemic children.
2.5 Was this the right sample to answer the objectives?
  Yes : young children presenting with significant fever to emergency department.
2.6 Is the study large enough to achieve its objectives? Have sample size estimates been performed?
  Probably but no mention of sample size estimates
2.7 Were all subjects accounted for?
  Only 154 children were enrolled in the time period which seems a small number for a busy emergency department and no mention of children presenting but not enrolled is made.
2.8 Were all appropriate outcomes considered?
  No , only considered positive blood cultures as sign of bacterial infection but not urine culture or focal signs of bacterial infection (e.g.cellulitis etc.)
2.9 Has ethical approval been obtained if appropriate?
3 Measurement and observation
3.1 Is it clear what was measured, how it was measured and what the outcomes were?
  Yes :
WCC and Neutropils
Outcome : difference in these measures between bacteraemiac and non-bactreaemic children
3.2 Was the assessment of outcomes blinded?
  Not formally but as assessors wouldn't know blood culture results at time of assessment effectively yes.
3.3 Was follow up sufficiently long and complete?
  No, as children with negative blood cultures were not followed up and this might have missed children with bacterial infections developing after initial assessment.
3.4 Are the measurements valid?
  Yos score has been evaluated in febrile infants and children and if above 10 does carry higher risk of bacterial infection but lower scores do not completely rule out bacterial infection.
WCC > 15000 and neutrophil count >10000 increase risk of bacterial infection but negative results do not rule out bacterial infections
3.5 Are the measurements reliable?
  YOS has reasonable interobserver agreement in previous assessments
WCC and Neutrophils are accurate measurements
3.6 Are the measurements reproducible?
  Yes with limitations for YOS
4 Presentation of results
4.1 Are the basic data adequately described?
4.2 Are the results presented clearly, objectively and in sufficient detail to enable readers to make their own judgement?
4.3 How large are the effects within a specified time?
  Total number 154 children of which bacteraemic : 19, 4 had meningitis as proven by LP subsequently.
Analysis divided into 3 groups :negative blood culture, bacteraemic and meningitis.
All 3 group showed similar response in temperature reduction with cooling and paracetamol.
Bacteraemic and non- bacteraemic group showed no difference in YOS.
However subgroup with meningitis did not show improvement in YOS despite same fever reduction
4.4 Are the results internally consistent, i.e. do the numbers add up properly?
5 Analysis
5.1 Are the data suitable for analysis?
5.2 Are the methods appropriate to the data?
5.3 Are any statistics correctly performed and interpreted?
6 Discussion
6.1 Are the results discussed in relation to existing knowledge on the subject and study objectives?
6.2 Is the discussion biased?
7 Interpretation
7.1 Are the author's conclusions justified by the data?
  Yes ,
reduction in fever with antipyretics and cooling does not distinguish between bacterial and non- bacterial infections
7.2 What level of evidence has this paper presented? (using CEBM levels)
7.3 Does this paper help me to answer my problem?
  within limits
After CA, i rated this paper: 7/10
8 Implementation
8.1 Can any necessary change be implemented in practice?
  Awareness for all staff assessing children that reduction in fever with physical measures and antipyretics will lead to clinical improvement both in viral and bacterial infections and does not reliably distinguish between the 2 (with the possible exception of meningitis - although small numbers)
Initial assessment should still be taken into account and also parents be made aware of this.
8.2 What aids to implementation exist?
  Include into guidance for assesment of febrile child
8.3 What barriers to implementation exist?
  Common perception that fever reduction does reduce risk of serious infection
8.4 Are the study patients similar to your own?
8.5 Does the paper give any conclusions that will affect what you will offer or tell your patient?
  Yes : Make parents aware that response to paracetamol does not rule out serious infections and if other concerns exist they should still seek medical attention