Table 1.

Criteria used for the classification of isolates in respect to their biofilm formation

Criteria	Biofilm-formation capacity
ODs ≤ODc	No biofilm producer
ODc≤ ODs ≤ 2×ODc	Weak biofilm producer
2 × ODc ≤ ODs ≤ 4 × ODc	Moderate biofilm producer
ODs> ODc×4	Strong biofilm producer