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imt (version 1.0.0)

coxsIndex: Cox's Proportional Hazards Index (Cox's C)

Description

Calculates Cox's C, a standardized effect size measure for comparing hazard rates between two groups in survival analysis.

Usage

coxsIndex(p_t, p_c, n_t, n_c)

Value

The calculated Cox's C effect size.

Arguments

p_t

Numeric value representing the proportion of events (e.g., failures, deaths) in the treatment group.

p_c

Numeric value representing the proportion of events in the control group.

n_t

Numeric value representing the sample size of the treatment group.

n_c

Numeric value representing the sample size of the control group.

Details

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.

References

Cox, D. R. (1972). Regression models and life-tables. Journal of the Royal Statistical Society: Series B (Methodological), 34(2), 187-202.