Sputum colour as a marker for bacteria in acute exacerbations of COPD: protocol for a systematic review and meta-analysis.
Ruan SpiesMatthew PotterRuan HollambyStefan van der WaltAmeer HohlfeldEleanor OchodoRichard N van Zyl-SmitPublished in: Systematic reviews (2021)
PROSPERO CRD42019141498.