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. 1986 Nov;41(11):824–829. doi: 10.1136/thx.41.11.824

Clinical trials in acute severe asthma: are type II errors important?

M J Ward
PMCID: PMC460505  PMID: 3824268

Abstract

Many studies in acute severe asthma have had low power. Fifteen randomised double blind studies investigating the treatment of acute severe asthma published during 1974-84 were analysed for power and 95% confidence limits. Twelve studies failed to detect a significant difference in bronchodilatation produced by two treatments and reported the treatments to produce equal effect. Each study had, however, less than a 60% probability of detecting a true 25% difference in bronchodilatation.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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