BMJ  2006;333:395 (19 August), doi:10.1136/bmj.333.7564.395-a

Letter

Antibiotics and acute purulent rhinitis

There is no significant difference between antibiotics

EDITOR—Arroll and Kenealy suggest that amoxicillin may be the preferred antibiotic for purulent rhinitis.¹ The pooled effect of the two studies using amoxicillin was significant (relative risk 1.26 (95% confidence interval 1.11 to 1.45)), while cefalexin did not achieve significance in one study (relative risk 0.62 (0.26 to 1.47)). Altman and Bland have pointed out that reporting the P values of subgroups is not the correct method to compare the treatments, as it is confounded by the number of subjects in each group.² When the method suggested by Altman and Bland is used to compare the studies using amoxicillin directly to the study using cefalexin the relative risk reduction is 0.49 (0.20 to 1.18) (P = 0.11). This does not confirm a significant difference between the two antibiotics. Moreover, as the authors point out, half of the participants in the study by De Sutter et al had unilateral facial pain,³ and this may also further confound this comparison. The data presented do not justify a preference in choice of antibiotic.

Manor View Practice, Bushey Health Centre, Bushey WD23 2NN chris.cates{at}nhs.net

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Competing interests: None declared.

References

1. Arroll B, Kenealy T. Are antibiotics effective for acute purulent rhinitis? Systematic review and meta-analysis of placebo controlled randomised trials. BMJ 2006;333: 279-81. (5 August.)[Abstract/Free Full Text]
2. Altman DG, Bland JM. Interaction revisited: the difference between two estimates. BMJ 2003;326: 219.[Free Full Text]
3. De Sutter AI, De Meyere MJ, Christiaens TC, van Duriel ML, Peersman W, De Maeseneer JM. Does amoxicillin improve outcomes in patients with purulent rhinorrhea? J Fam Pract 2002;51: 317-23.[ISI][Medline]

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