"If you know of a reliable and valid tool to distinguish viral from bacterial OM....."
Well there isn't one. A red drum and a child with viral type symptoms is probably viral. Stinky pus and a perf is bacterial. In between it's a best guess.
How reliable and how valid does it have to be for you to accept it? 100% or would a good "based on experience" guess do? Ooops, experience doesn't count!
Anyway, thank God, I at least get wiser as I get older and better at getting my guesses right.
