Review Article

Prognostic Models for Predicting Overall Survival in Patients with Primary Gastric Cancer: A Systematic Review

Table 4

Characteristics of models with external validation and those without.

Externally validated models (n = 20) mean (SD)Not externally validated models (n = 81) mean (SD) value

Training sample size3902.55 (5777.62)634.17 (926.30)0.021
Number of events2825.12 (4069.04)344.75 (613.35)0.028
Number of candidate predictors75.80 (204.53)12.83 (28.26)0.185
EPV364.21 (542.04)44.70 (82.97)0.033
Number of final predictors6.65 (3.44)5.94 (6.08)0.490
Length of follow-up (month)64.24 (29.65)43.76 (19.15)0.122
Age63.00 (4.99)59.87 (3.39)0.034
Male%64.92 (4.10)67.29 (6.54)0.053
c statistic0.80 (0.06)0.75 (0.07)0.042

EPV: event per variable.