Premise: QA practices within an aquatic toxicology laboratory must address all activities that affect the quality of the final effluent toxicity data, such  (1) effluent sampling and handling; (2) the source and condition of the test organisms; (3) condition and operation of equipment; (4) test conditions; (5) instrument calibration; (6) replication;

Hypothesis: There is no link between data and practices.
Relation: contradiction