The diagnosis of acute suppurative otitis media is not as easy and straightforward as it may seem. Many of the signs and symptoms in children with acute otitis media are also observed in children without it. Furthermore, several of the "classic" findings of acute otitis media, such as fever and earache, are often absent, even in cases confirmed by myringotomy. An otoscope with a fresh bulb and a good power source, as well as a view of the tympanic membrane that is not obstructed by cerumen, are essential to making the diagnosis of acute otitis media. A bulging, cloudy, immobile tympanic membrane is highly associated with otitis media. Erythema of the eardrum alone, however, is often the result of viral infection, crying or attempts to remove cerumen and should not be the sole basis for the diagnosis of acute otitis media. To avoid the common problem of overdiagnosing acute otitis media, the clinician should consider the predictive values of the various symptoms and physical examination findings associated with ear infections.