This was an open randomized trial, which may affect perception of symptoms by parents and medical staff. The lack of placebo or blinding of the study may lead to a more careful registration of symptoms in patients without antibiotic treatment, which could overestimate the occurrence of symptoms and lead to more phone contacts or new visits. The study showed a higher incidence of new visits among those not treated with PcV, but not on median recovery time, of perforations or therapeutic failures.
All participating staff members received careful instructions and education on AOM by study nurses and the project leader. The doctors are all familiar with the aural microscope. The very strict inclusion criteria would ensure that all included patients had a purulent AOM since our primary aim was to evaluate those patients who, according to the new guidelines, could be managed without antibiotic treatment. However, the relatively small number of patients (n
179) is a limitation of the study and this number is substantially less than was initially intended in order to reach a desirable power (>80%) for most of the clinically important differences. After two years, the allocation of patients asymptotically reached a plateau and the study, therefore, had to be closed. The reasons for this decline may be that the recommendation of antibiotic restriction was spreading in the community and that people therefore adopted a wait-and-see policy. The limited number of patients resulted in relatively low power, especially as concerns small counts (low proportions). That means that it is not possible to separate statistically the almost threefold number of children having moderate or severe pain at day 2 in the non-pc group compared with the pc group (8 and 3 children, respectively, corresponding to 10% and 3%; see ) (p
0.12), or the difference between 0 and 4 children presenting with treatment failure (ear-drum perforation) at days 2–7 (see ).
Our results were in concordance with most placebo-controlled studies. Nicole Le Saux et al. 
enrolled 512 children with moderate severity of AOM, and showed that children who received amoxicillin had less pain and fever during the first two days. Their study could not show any statistical differences in recurrence rates or middle-ear effusion. Mygind et al. 
, in a double-blind, placebo-controlled study of 149 children, found that PcV decreased the number of days with pain but that there was no major difference in outcome or complications between the PcV and the placebo group. The study concluded that the attitude of “masterly inactivity” with regard to the treatment of AOM was justifiable, provided sufficient analgesic treatment was given and the patient could be closely followed up.
In daily practice, all treatment choices are open and placebos are not allowed. We found that the total number of new consultations was higher in the no antibiotics group, 18% as compared with 4% in the PcV group. However, the cumulative number of patients recovering in all treatment groups did not differ (see ), and it can be argued that the observed difference might be due to the open design. In the open study by Little et al. 
, children with AOM were randomized to either immediate treatment with antibiotics or to wait and see for at least 72 hours before considering collecting the prescribed antibiotic. In the wait-and-see group, 24% of children did collect their antibiotic prescription which can be compared with the 18% of children randomized to no antibiotics in our study who revisited, of whom 5% received antibiotics because of treatment failure. It seems probable that the number of revisits would decline once not prescribing antibiotics is the established strategy and generally accepted both among staff and in the general population
It is a well-known fact that high usage of antibiotics is a major risk factor for development and spread of antimicrobial resistance [14–17]
. There are also indications that PcV might have less negative ecological effects than most other antibiotic choices 
. Although antibiotic use by children has decreased by approximately 50% in Sweden during the last decade, resistance rates in pneumococci
have not declined 
. Thus, when evaluating the positive effects of antibiotic treatment of AOM, the risk of increased spread of antimicrobial resistance and increased individual side effects must be taken into account.
The most feared complication of AOM, acute mastoiditis, is rare and the low incidence rate demands long-term surveys on a regional or national basis in order to discover changes in incidence rate due to changes in treatment policy in the treatment of AOM [