highly significantp<0.0001
By regression analysis a highly significant inverse relationship was found between the AFB score and the mean TTD of each culture system (BacT/ALERT MP: R 2 = 0.924; LJ: R2 = 0.885) (p<0.0001) and a significant difference was observed for all the categories of the mycobacterial yield (p<0.0001) ( Figure 3 ).