Calculation of sample size when planning a clinical study of the Bovhyaluronidaze azoximer preparation in companion animals urological practice
Nowadays both international and Russian medical sciences are actively working to improve the methods of evidence and the formation of standards of research and treat-ment. The necessity to develop common criteria for evaluating the effectiveness of methods of diagnosis, treatment and prevention of diseases exists in veterinary medicine. To achieve this goal, both general veterinary medicine and scientific research in the field of veterinary medicine, must reach the level of evidence that answers the requirements of Evidence Based Medicine. In accordance with the current require-ments of Evidence Based Medicine and Good Clinical Practice, at the stage of plan-ning a clinical study of the use of Bovhyalu-ronidaze azoximer preparations in the com-panion animals urological treatment, we have calculated the required sample size. In the calculation, we used the results of a pilot study, in which the incidence of post-operative complications in the experimental group was 0.10, in the control group — 0.55. We calculated that for statistical significance testing with significance level α = 0.05 and power β = 0.80 in a clinical trial of the use of bovhyaluronidaze azoximer prepara-tion in the urological practice of companion animals, the sample size should be at least 22 animals in each group (taking into ac-count the possible retirement of patients from the clinical study). And the groups must be equal in volume to achieve the max-imum test power.