Thirty-five RCTs were included in the review (number of participants not reported). Details on study quality were lacking.
There was no significant difference between treatment groups in terms of incidence of overall treatment failure at one month (38 RCTs). There was no evidence of heterogeneity (p=0.468). Subgroup analyses based on short-course antibiotic, age (<2 vs >2 years), presence/absence of perforated eardrum, recurrent otitis media and different isolated micro-organisms showed no significant differences between treatment groups. Results were similar for other outcomes, which included clinical treatment failure in culture positive otitis media patients (five RCTs), bacteriological failure (seven RCTs), persistent middle ear effusion (six RCTs), relapse (12 RCTs) and recurrence (seven RCTs).
When treatment failure was redefined so that subjects who showed improvement were redefined as treatment failure there was a significant reduction in favour of patients on short-term therapy (RR 0.83, 95% CI 0.70 to 0.98; 28 RCTs). Outcomes at 10 to 14 days and between one and three months showed no difference between treatment groups, except for the incidence of recurrence at between one and three months where there was a significant reduction in favour of patients on short-term therapy (RR 0.56, 95% CI 0.36 to 0.85; three RCTs).
Overall incidence of adverse events was less in the short-course group (RR 0.58, 955 CI 0.48 to 0.70; 20 RCTs), with a significantly reduced incidence of diarrhoea (RR 0.61, 95% CI 0.38 to 0.97; 20 RCTs) and vomiting (RR 0.67, 95% CI 0.46 to 0.98; 12 RCTs). There was no significant difference in incidence of rash or abdominal pain.
There was no evidence of publication bias.