Survival times in months for two groups - YOUR NAME 1 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 The data as SAS sees it Obs group months status 1 Treated 16 1 2 Treated 18 1 3 Treated 20 1 4 Treated 23 0 5 Treated 24 1 6 Control 15 0 7 Control 18 0 8 Control 19 0 9 Control 19 0 10 Control 20 0 Survival times in months for two groups - YOUR NAME 2 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 Lifetest plots and tests The LIFETEST Procedure Stratum 1: group = Control Product-Limit Survival Estimates Survival Standard Number Number months Survival Failure Error Failed Left 0.0000 1.0000 0 0 0 5 15.0000 0.8000 0.2000 0.1789 1 4 18.0000 0.6000 0.4000 0.2191 2 3 19.0000 . . . 3 2 19.0000 0.2000 0.8000 0.1789 4 1 20.0000 0 1.0000 0 5 0 Summary Statistics for Time Variable months Quartile Estimates Point 95% Confidence Interval Percent Estimate [Lower Upper) 75 19.0000 18.0000 20.0000 50 19.0000 15.0000 20.0000 25 18.0000 15.0000 19.0000 Mean Standard Error 18.2000 0.8602 Survival times in months for two groups - YOUR NAME 3 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 Lifetest plots and tests The LIFETEST Procedure Stratum 2: group = Treated Product-Limit Survival Estimates Survival Standard Number Number months Survival Failure Error Failed Left 0.0000 1.0000 0 0 0 5 16.0000* . . . 0 4 18.0000* . . . 0 3 20.0000* . . . 0 2 23.0000 0.5000 0.5000 0.3536 1 1 24.0000* . . . 1 0 NOTE: The marked survival times are censored observations. Summary Statistics for Time Variable months Quartile Estimates Point 95% Confidence Interval Percent Estimate [Lower Upper) 75 . 23.0000 . 50 . 23.0000 . 25 23.0000 23.0000 . Mean Standard Error 23.0000 . Survival times in months for two groups - YOUR NAME 4 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 Lifetest plots and tests The LIFETEST Procedure NOTE: The mean survival time and its standard error were underestimated because the largest observation was censored and the estimation was restricted to the largest event time. Summary of the Number of Censored and Uncensored Values Percent Stratum group Total Failed Censored Censored 1 Control 5 5 0 0.00 2 Treated 5 1 4 80.00 --------------------------------------------------------------- Total 10 6 4 40.00 Survival times in months for two groups - YOUR NAME 5 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 Lifetest plots and tests The LIFETEST Procedure Survival Function Estimates S SDF | u 1.0 + *-------------------------------------C-------------------T r | | | v | | | i | | | v | | | a 0.8 + C------C | l | | | | | | D | | | i | | | s 0.6 + C--C | t | | | r | | T i | | b | | u 0.4 + | t | | i | | o | | n | | 0.2 + C-C F | | u | | n | | c | | t 0.0 + C i ----+----+----+----+----+----+----+----+----+----+----+----+----+---- o 0 2 4 6 8 10 12 14 16 18 20 22 24 n months Survival times in months for two groups - YOUR NAME 6 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 Lifetest plots and tests The LIFETEST Procedure Censored Observations Strata T + T T T T C + -----+----+----+----+----+----+----+----+----+----+----+----- 0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 months Legend for Strata Stratum Symbol group 1 C Control 2 T Treated Survival times in months for two groups - YOUR NAME 7 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 Lifetest plots and tests The LIFETEST Procedure Testing Homogeneity of Survival Curves for months over Strata Rank Statistics group Log-Rank Wilcoxon Control 2.7500 18.000 Treated -2.7500 -18.000 Covariance Matrix for the Log-Rank Statistics group Control Treated Control 1.08750 -1.08750 Treated -1.08750 1.08750 Covariance Matrix for the Wilcoxon Statistics group Control Treated Control 58.4000 -58.4000 Treated -58.4000 58.4000 Survival times in months for two groups - YOUR NAME 8 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 Lifetest plots and tests The LIFETEST Procedure Test of Equality over Strata Pr > Test Chi-Square DF Chi-Square Log-Rank 6.9540 1 0.0084 Wilcoxon 5.5479 1 0.0185 -2Log(LR) 3.3444 1 0.0674 Survival times in months for two groups - YOUR NAME 9 Two groups of patients after surgery 02:50 Tuesday, September 20, 2005 THE SECOND DATASET IS THE SAME AS THE FIRST DATASET ! Obs group status months 1 Treated 1 16 2 Treated 1 18 3 Treated 1 20 4 Treated 0 23 5 Treated 1 24 6 Control 0 15 7 Control 0 18 8 Control 0 19 9 Control 0 19 10 Control 0 20