Date	Event	Description
26 April 2015	New citation required but conclusions have not changed	The conclusions regarding the effectiveness and safety of antibiotics have essentially not changed, except for some new outcomes (e.g. long‐term effects on AOM recurrences) and minor changes to the risk of bias.
26 April 2015	New search has been performed	We updated the searches in April 2015. In this updated review, we now provide outcome data on: pain at 24 hours, two to three days, four to seven days and 10 to 14 days (in earlier versions outcome data on pain were presented at 24 hours, two to three days and four to seven days); abnormal tympanometry findings at two to four weeks, six to eight weeks and three months (in earlier versions outcome data on abnormal tympanometry findings were presented at four to six weeks and three months); long‐term effects including number of parent‐reported AOM‐symptom episodes, antibiotic prescriptions, health care utilisation as assessed at least one year after randomisation (in earlier versions no data on long‐term effects were presented). The outcome 'Adverse effects likely to be related to the use of antibiotics such as vomiting, diarrhoea or rash' has been added to primary outcomes (in earlier versions this outcome was listed as a secondary outcome) according to the recommendations described in Chapter 5.4.2 of the Cochrane Handbook for Systematic Reviews of Interventions ("the primary outcomes should include at least one desirable and at least one undesirable outcome") (Higgins 2011). One new trial was identified for the review of antibiotics against placebo (Tapiainen 2014). This study included children aged between six months and 15 years and provided data on pain at days four to seven, adverse effects likely to be related to the use of antibiotics, abnormal tympanometry findings at two to four weeks and six to eight weeks, tympanic membrane perforation and serious complications. New data were added to the review from previously included trials. For the review of antibiotics against placebo: data on pain at 10 to 12 days (Hoberman 2011); data on abnormal tympanometry findings at two to four weeks (Kaleida 1991); data on long‐term effects (Burke 1991; Damoiseaux 2000). For the review of immediate antibiotics against expectant observation: data on pain at 11 to 14 days (Spiro 2006); data on abnormal tympanometry findings at two to four weeks (McCormick 2005); data on long‐term effects (Little 2001). We identified one ongoing trial (ACTRN12608000424303). The objective of this double‐blind, placebo‐controlled randomised clinical trial is to assess the effectiveness of azithromycin for seven days in aboriginal children with asymptomatic AOM, defined as a bulging tympanic membrane without associated symptoms at the time of diagnosis. The primary outcome is the proportion of children with a bulging tympanic membrane or ear discharge or withdrawn due to complications or side effects at 14 days. Quality of evidence is now described based on the GRADE framework.