Question: Is this describing a (1) directly correlative relationship, (2) conditionally causative relationship, (3) causative relationship, or (0) no relationship.

The use of 0.5% levobupivacaine in comparison with 0.5% levobupivacaine with 2% lidocaine solution for PVB had a longer time-to-block onset, but it also reduced hemodynamic disturbances and prolonged the analgesic effect.
user
This no relationship.
assistant