Continuous monitoring of clinical trials involving binary outcomes using Pocock-type boundaries (version 1.1) (c) Bahjat Qaqish (2004) (Simulation-based calculations) Defintions: K = the maximum planned sample size THETA = the event probability PHI = the desired probability of early stopping (hitting the boundary) Input K THETA PHI: 200 0.2 0.05 K = 200 THETA = 0.2 PHI = 0.05 PHI* = 0.049206 = the actual probability of hitting the upper boundary ALPHA = 0.00693154 = the pointwise stopping probability The upper boundary is: b[1] = 2 b[2] = 3 b[3] = 4 b[4] = 4 b[5] = 4 b[6] = 5 b[7] = 5 b[8] = 6 b[9] = 6 b[10] = 6 b[11] = 7 b[12] = 7 b[13] = 8 b[14] = 8 b[15] = 8 b[16] = 9 b[17] = 9 b[18] = 9 b[19] = 9 b[20] = 10 b[21] = 10 b[22] = 10 b[23] = 11 b[24] = 11 b[25] = 11 b[26] = 12 b[27] = 12 b[28] = 12 b[29] = 13 b[30] = 13 b[31] = 13 b[32] = 13 b[33] = 14 b[34] = 14 b[35] = 14 b[36] = 15 b[37] = 15 b[38] = 15 b[39] = 15 b[40] = 16 b[41] = 16 b[42] = 16 b[43] = 16 b[44] = 17 b[45] = 17 b[46] = 17 b[47] = 18 b[48] = 18 b[49] = 18 b[50] = 18 b[51] = 19 b[52] = 19 b[53] = 19 b[54] = 19 b[55] = 20 b[56] = 20 b[57] = 20 b[58] = 21 b[59] = 21 b[60] = 21 b[61] = 21 b[62] = 22 b[63] = 22 b[64] = 22 b[65] = 22 b[66] = 23 b[67] = 23 b[68] = 23 b[69] = 23 b[70] = 24 b[71] = 24 b[72] = 24 b[73] = 24 b[74] = 25 b[75] = 25 b[76] = 25 b[77] = 25 b[78] = 26 b[79] = 26 b[80] = 26 b[81] = 26 b[82] = 27 b[83] = 27 b[84] = 27 b[85] = 28 b[86] = 28 b[87] = 28 b[88] = 28 b[89] = 29 b[90] = 29 b[91] = 29 b[92] = 29 b[93] = 30 b[94] = 30 b[95] = 30 b[96] = 30 b[97] = 31 b[98] = 31 b[99] = 31 b[100] = 31 b[101] = 32 b[102] = 32 b[103] = 32 b[104] = 32 b[105] = 33 b[106] = 33 b[107] = 33 b[108] = 33 b[109] = 34 b[110] = 34 b[111] = 34 b[112] = 34 b[113] = 35 b[114] = 35 b[115] = 35 b[116] = 35 b[117] = 35 b[118] = 36 b[119] = 36 b[120] = 36 b[121] = 36 b[122] = 37 b[123] = 37 b[124] = 37 b[125] = 37 b[126] = 38 b[127] = 38 b[128] = 38 b[129] = 38 b[130] = 39 b[131] = 39 b[132] = 39 b[133] = 39 b[134] = 40 b[135] = 40 b[136] = 40 b[137] = 40 b[138] = 41 b[139] = 41 b[140] = 41 b[141] = 41 b[142] = 42 b[143] = 42 b[144] = 42 b[145] = 42 b[146] = 43 b[147] = 43 b[148] = 43 b[149] = 43 b[150] = 44 b[151] = 44 b[152] = 44 b[153] = 44 b[154] = 44 b[155] = 45 b[156] = 45 b[157] = 45 b[158] = 45 b[159] = 46 b[160] = 46 b[161] = 46 b[162] = 46 b[163] = 47 b[164] = 47 b[165] = 47 b[166] = 47 b[167] = 48 b[168] = 48 b[169] = 48 b[170] = 48 b[171] = 49 b[172] = 49 b[173] = 49 b[174] = 49 b[175] = 49 b[176] = 50 b[177] = 50 b[178] = 50 b[179] = 50 b[180] = 51 b[181] = 51 b[182] = 51 b[183] = 51 b[184] = 52 b[185] = 52 b[186] = 52 b[187] = 52 b[188] = 53 b[189] = 53 b[190] = 53 b[191] = 53 b[192] = 53 b[193] = 54 b[194] = 54 b[195] = 54 b[196] = 54 b[197] = 55 b[198] = 55 b[199] = 55 b[200] = 55 THETA PHI* E[Y] SD[Y] E[N] SD[N] E[Y/N] SD[Y/N] 0.20 0.050 38.57 7.56 192.93 33.26 0.21 0.08 0.30 0.873 28.54 15.25 95.14 63.52 0.36 0.13 0.40 1.000 12.70 6.73 31.75 23.54 0.49 0.15 0.50 1.000 8.14 3.59 16.29 11.11 0.59 0.16 0.60 1.000 6.15 2.25 10.26 6.31 0.69 0.16 0.70 1.000 5.07 1.46 7.25 3.80 0.77 0.16 0.80 1.000 4.44 0.86 5.55 2.21 0.85 0.14 0.90 1.000 4.11 0.38 4.56 1.08 0.92 0.11 Defintions: Y = the number of events, random, between 0 and N N = the number of patients, random, between 1 and K PHI* = the actual probability of early stopping (hitting the boundary) E[ ] denotes the expected value (mean) SD[ ] denotes the standard deviation The boundary has been written to file _bndry_.dat in a format appropriate for reading into other supplied programs (e.g. cp3). Date and time: Mon Jul 26 11:59:38 2004