epi: Epidemiological 2 by 2 Analysis

In R4VN: Health Data Analysis and Publication-Ready Reporting

Epidemiological 2 by 2 Analysis

Description

epii() analyzes typed 2 by 2 counts. epi() analyzes binary outcome and exposure variables. With by, stratum-specific estimates, a Mantel-Haenszel common odds ratio, a pooled risk ratio, homogeneity, and interaction tests are displayed. The stratified output also reports the crude-versus-Mantel-Haenszel OR difference as both 100*(ORcrude-ORMH)/ORMH and 100*(ORcrude-ORMH)/ORcrude. cci()/cc() and csi()/cs() are familiar aliases.

Usage

epi(
  outcome,
  exposure,
  by = NULL,
  data = NULL,
  event = NULL,
  exposed = NULL,
  level = 0.95,
  correction = 0.5,
  digits = 3,
  p_digits = 3,
  show = TRUE,
  console = FALSE
)

cc(
  outcome,
  exposure,
  by = NULL,
  data = NULL,
  event = NULL,
  exposed = NULL,
  level = 0.95,
  correction = 0.5,
  digits = 3,
  p_digits = 3,
  show = TRUE,
  console = FALSE
)

cs(
  outcome,
  exposure,
  by = NULL,
  data = NULL,
  event = NULL,
  exposed = NULL,
  level = 0.95,
  correction = 0.5,
  digits = 3,
  p_digits = 3,
  show = TRUE,
  console = FALSE
)

epii(
  a = NULL,
  b = NULL,
  c = NULL,
  d = NULL,
  by = NULL,
  level = 0.95,
  correction = 0.5,
  digits = 3,
  p_digits = 3,
  show = TRUE,
  console = FALSE
)

cci(a, b, c, d, ...)

csi(a, b, c, d, ...)

epi(
  outcome,
  exposure,
  by = NULL,
  data = NULL,
  event = NULL,
  exposed = NULL,
  level = 0.95,
  correction = 0.5,
  digits = 3,
  p_digits = 3,
  show = TRUE,
  console = FALSE
)

Arguments

outcome	Binary outcome variable.
exposure	Binary exposure variable.
by	For epii(), a list of 2 by 2 tables or a 2 by 2 by K array. For epi(), an optional stratification variable. Hierarchical syntax is supported: by = vars(province, sex) repeats the epidemiological analysis within province and uses sex as the innermost Mantel-Haenszel stratum. With three or more variables, every variable before the final one is an ordered outer stratum and the final variable is the MH stratification variable.
data	Data frame. If NULL, active data is used.
event	Outcome event level; defaults to the last observed level.
exposed	Exposure level; defaults to the last observed level.
level	Confidence level.
correction	Continuity correction used for log-scale confidence intervals when a cell is zero.
digits, p_digits	Decimal places for estimates and p-values.
show	Logical; open the formatted result in the Viewer. Default TRUE.
console	Logical; also print the traditional text result in the Console. Default FALSE.
a, b, c, d	Cell counts of a 2 by 2 table. a may also be a 2 by 2 matrix.
...	Additional arguments passed to epii() by immediate aliases.

Details

The 2 by 2 layout is exposure by outcome: a exposed cases, b exposed noncases, c unexposed cases, and d unexposed noncases.

Value

Invisibly returns an object of class r4vn_stat.

Examples

epii(40, 10, 20, 30)
epii(by = list(
  Female = c(12, 18, 8, 32),
  Male = c(28, 12, 12, 18)
))

R4VN documentation built on Sept. 30, 2026, 5:13 p.m.