Hi I also did an EBM search a while back and I hope this helps you in your search.

You could try to search for evidence on specific components of chest PT like bronchial hygiene, airway clearance techniques, directed coughing, huffing, ACBT, AD, breathing exercises, etc. etc. Chest PT is a very vague phrase. It doesn't have any "standard" definition or components in scientific literature. Some studies don't even list down what components of chest PT were scrutinized.

I could also email you some of the articles I found. Just tell me your specific topics and send me your email addy at [email protected]

Good luck!