ca Ozgur 2006

Methods	Single‐blind prospective study carried out during the 2003 to 2004 season in children from 8 day care nurseries around Ankara, Turkey. The study aim was to assess the effectiveness of TIV in preventing AOM and OME. Randomisation is not mentioned, comparator is do‐nothing and denominators are uneven. The single‐blind design refers to the ear, nose and throat (ENT) tympanomtrist. The influenza period was defined as 15 Dec 2003 to 31 Jan 2004 on the basis of influenza and RSV isolates in the community. Three other influenza periods are also described
Participants	135 healthy daycare children aged 6 to 60 months. 16 children were excluded from the study (3 because of tympanostomy tubes, 11 because they could not complete the minimum of 3 follow‐up visits and 3 because of failure to have the second vaccination). The authors report their analysis for 119 children (61 vaccinated and 58 UV, mean age 43 months). There were 22 children aged less than 2 years. The arms were similar for breast feeding, gender, dummy use, history of frequent URTIs, antibiotic use, allergy, asthma, previous OM and passive smoking
Interventions	TIV containing A/Moscow/10/99 (H3N2), A/New Caledonia/20/99 (H1N1) or B/Hong Kong/330/2001 in 2 doses (Fluarix or Vaxigrip). No mention is made of the circulating strains, although content of the vaccine was that recommended by WHO
Outcomes	Effectiveness OM diagnosed at tympanometry and otoscopy by a blinded ENT surgeon: normal ear (no abnormality and type A and C1 curves on tympanometry), AOM (hyperemia, opacity, bulging or immobility of the TM together with any of the following: fever, earache, irritability and vomiting), OME (retraction, opacity, bulging or immobility of the TM without clinical signs and with C2 or B tympanometry curve), OM (any episode of either AOM or OME)
Funding Source	Unclear
Notes	The authors conclude that "The frequencies of AOM, OME and total otitis media episodes in vaccinated children were 2.3%, 22.8% and 25.2%, respectively and these frequencies were 5.2%, 31.1% and 36.3% in the UV group. The difference was statistically significant (P < 0.01). This difference was especially prominent in the influenza season (P < 0.05). Influenza vaccine is effective in reducing AOM and OME episodes in 6‐ to 60‐month‐old day care children, especially during influenza season". The message is mixed as the authors point out that the relatively low effectiveness of TIV makes mass vaccination to prevent an OM (a syndrome) impractical. Not very detailed report, likely to be a cohort or CCT. Confusingly reported outcome data in Table 2. Numerators were extracted from the text
Risk of bias
Bias	Authors' judgement	Support for judgement
PCS/RCS‐Selection Exposed cohort	Unclear risk	Insufficient description
PCS/RCS‐Selection Non Exposed cohort	Unclear risk	Insufficient description
PCS/RCS‐Comparability	High risk	Possibly confounding by indication
PCS/RCS‐Assessment of Oucome	Unclear risk	Secure record
Summary assessments	High risk	Possibly companioning by indication