Question

In a study to investigate the effectiveness of an anticoagulant, 10 rats are randomly assigned to each of two groups. The rats in the first group receive an injection of the anticoagulant, while those in the second group receive a control saline injection. Samples of blood are taken from each rat before and after treatment and the coagulation time in minutes noted. The following method might be appropriately used to test the hypothesis that the mean coagulation time is not affected by treatment:

1. paired t –test
2. one-way analysis of variance of the pre-treatment values
3. the correlation between pre-treatment and post-treatment values
4. analysis of covariance
5. contingency table analysis

Answer 1

3. the correlation between pre-treatment and post-treatment values

Explanation:

two treatment groups (A and B). Rats were subcutaneously injected with carrageenan to induce thrombosis. Rats in the treatment group A were intragastrically administered with Huisheng Oral Solution at a dose of 2 ml/100 g body weight (once per 8 hours), 72 hours after carrageenan injection, while those in the treatment group B were administered with Huisheng Oral Solution both 72 hours before and after induction of thrombosis.