Mean and median time to microbial detection for volume-compliant bottle sets by Virtuo and BTA3D and mean bottle fill volumes for clinically significant isolates recovered from both study bottles in each paira

Organism groupnMean TTD (h)P valuebMedian TTD (h)P valuecMean fill, ml
Coagulase-negative staphylococci1420.621.40.67819.420.80.0784.13.9
Enteric Gram-negative bacilli4311.114.7<0.0018.611.0<0.0014.74.6
Enterococcus spp.1810.612.9<0.00111.413.4<0.0014.34.4
Staphylococcus aureus 3020.820.50.81916.119.20.5804.74.6
Streptococcus spp.911.714.50.2218.610.40.0982.32.6
  • a Results shown are for bottle sets where clinically significant, monomicrobial isolates were recovered from both bottles. Six outliers with a difference in time to microbial detection (TTD) of ≥24 h, suggestive of greatly different organism loads at the time of bottle inoculation, were excluded from this analysis.

  • b Data represent TTD means. A t test was used to evaluate the mean of the differences.

  • c Data represent TTD medians. A signed-rank test was used to evaluate the median of the differences in TTD since the TTD data were not normally distributed.