Calculates Cox's C, a standardized effect size measure for comparing hazard rates between two groups in survival analysis.
coxsIndex(p_t, p_c, n_t, n_c)
The calculated Cox's C effect size.
Numeric value representing the proportion of events (e.g., failures, deaths) in the treatment group.
Numeric value representing the proportion of events in the control group.
Numeric value representing the sample size of the treatment group.
Numeric value representing the sample size of the control group.
Cox's C is a useful effect size for survival analysis when hazard ratios are not constant over time. It's calculated based on the log odds ratio of events and includes a small sample size correction. The value 1.65 is used to approximate a conversion to a Cohen's d-like scale.
Cox, D. R. (1972). Regression models and life-tables. Journal of the Royal Statistical Society: Series B (Methodological), 34(2), 187-202.