Best Evidence Topics

Randomised control trial

Bjornson, CL, et al.
A randomized trial of a single dose of oral dexamethasone for mild croup
N Engl J Med
Sept 23, 2004; 1306-1313
  • Submitted by:Kathleen Blazek - Emergency Medicine Resident
  • Institution:Grand Rapids MERC
  • Date submitted:5th July 2005
Before CA, i rated this paper: 8/10
1 Objectives and hypotheses
1.1 Are the objectives of the study clearly stated?
  yes, to assess benefit of dexamethasone for mild croup
2 Design
2.1 Is the study design suitable for the objectives
  yes, randomized, double-blind, placebo-controlled trial
2.2 Who / what was studied?
  children with mild croup (croup score less than or equal to 2)
2.3 Was this the right sample to answer the objectives?
  yes, 4 pediatric emergency departments
2.4 Is the study large enough to achieve its objectives? Have sample size estimates been performed?
  yes, sample of 350 patients per group gives P=0.05
2.5 Were all subjects accounted for?
  No, follow-up data not available for 708 of the 720 enrolled patients
2.6 Were all appropriate outcomes considered?
2.7 Has ethical approval been obtained if appropriate?
  yes, written informed consent of parents
2.8 Were the patients randomised between treatments?
2.9 How was randomisation carried out?
  computer generated randomization, identical taste/appearance of placebo, and blinded codes
2.10 Are the outcomes clinically relevant?
  yes, the primary outcome was a return to a medical care provider for croup within 7 days after treatment
3 Measurement and observation
3.1 Is it clear what was measured, how it was measured and what the outcomes were?
  yes, via telephone interview, secondary outcomes were the presence of ongoing symptoms of croup, economic costs, hours of sleep lost by the child, and parental stress
3.2 Are the measurements valid?
3.3 Are the measurements reliable?
3.4 Are the measurements reproducible?
  yes, interview methods provided
3.5 Were the patients and the investigators blinded?
  yes, codes kept in pharmacy
4 Presentation of results
4.1 Are the basic data adequately described?
4.2 Were groups comparable at baseline?
  yes, slightly milder croup scores in placebo group
4.3 Are the results presented clearly, objectively and in sufficient detail to enable readers to make their own judgement?
  yes, the findings were consistent across a range of clinical, social, and economic outcome measures
4.4 Are the results internally consistent, i.e. do the numbers add up properly?
4.5 Were side effects reported?
  adverse effects were reported, however, the study was not sufficiently powered to exclude the possibility of rare adverse events
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 authors' conclusions justified by the data?
7.2 What level of evidence has this paper presented? (using CEBM levels)
7.3 Does this paper help me answer my problem?
After CA, i rated this paper: 9/10
8 Implementation
8.1 Can any necessary change be implemented in practice?
8.2 What aids to implementation exist?
  simple treatment, cost-effective, no serious adverse effects
8.3 What barriers to implementation exist?
  Some might argue that the use of dexamethasone in children with mild croup is unnecessary, since objectively, symptoms are mild and self-limited.
It is possible that a smaller dose of dexamethasone may be as effective as the 0.6 mg/kg that was administered.