As a follow-up study, we performed a subsequent prospective analysis in 1999, based on direct observation. The purpose of the study was to determine if rinsing the mouth prior to expectoration influenced sputum specimen quality, based on Gram stain analysis.3 For this study, patients expectorated, rinsed their mouths three times with tap water, then expectorated again. Patients were observed (by L.A.G.) during rinsing and collections, and both specimens (before and after rinsing) were promptly delivered to the Microbiology Section, where Gram stains were performed (by D.J.F.) and the results were evaluated. Specimens were graded as good ( < 10 squamous epithelial cells [SECs]), fair (11–19 SECs), poor ( > 20 SECs, > 10 WBCs), and inadequate ( > 20 SECs, < 10 WBCs), per objective magnification (100×).