Fig. 3

The quality of the samples was adequate for testing with a PCR-based assay. Laboratory survey questions pertaining to the quality of the samples are shown on the x-axis (from Additional files 3 and 5). Data points represent the mean response, green dots represent samples collected from the pilot study and blue dots represent samples collected from the at-home collection kit. Survey responses were reported on a scale of 1 (strongly disagree) to 5 (strongly agree). Samples with less favorable responses are highlighted in red. Mean and standard deviation (st. dev.) are shown in black. The graph on the right shows the cycle threshold (Ct) values for the internal control RNAse P (RP) from each of the saliva samples submitted. The dots represent Ct value per participant. Ct values over 35 are considered invalid and are highlighted in gray. P-value is shown using one-way Mann–Whitney. Mean and standard deviation (st. dev.) are shown in black