176 Section 1 The Epidemiologic Approach To Disease And Intervention Number Of Patients Needed In An Experimental And A 1 (68.84 KiB) Viewed 68 times
176 Section 1 The Epidemiologic Approach To Disease And Intervention Number Of Patients Needed In An Experimental And A 2 (68.84 KiB) Viewed 68 times
176 Section 1 THE EPIDEMIOLOGIC APPROACH TO DISEASE AND INTERVENTION Number of Patients Needed in an Experimental and a Control Group for a Given Probability of Obtaining a Significant Result (Two-Sided Test) Lower of the Two Cure Rates 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 DIFFERENCES IN THE CURE RATES BETWEEN THE TWO TREATMENT GROUPS 0.20 0.25 0.30 44 36 59 71 0.05 420 680 910 1,090 1,250 1,380 1,470 1,530 0.10 130 195 250 290 330 360 370 390 0.15 69 96 120 135 150 Question 8 is based on the above table: 8. A drug company maintains that a new drug G for a certain disease has a 50% cure rate as com- pared with drug H, which has only a 25% cure rate. You are asked to design a clinical trial com- paring drugs G and H. Using the preceding table, estimate the number of patients needed in each 160 170 175 a= 0.05; power (1-B)=0.80. Data from Gehan E: Clinical trials in cancer research. Environ Health Perspect 32:31, 1979. 80 88 93 96 97 41 48 53 57 60 61 61 31 35 39 2 4 H 42 44 44 44 44 therapy group to detect such a difference with α = 0.05, two-sided, and B=0.20. The number of patients needed in each therapy group is.
Join a community of subject matter experts. Register for FREE to view solutions, replies, and use search function. Request answer by replying!