lgor_lgrr: Covariance between log odds ratio and log risk ratio

View source: R/mix.vcov.R

lgor_lgrrR Documentation

Covariance between log odds ratio and log risk ratio

Description

Compute covariance between log odds ratio and log risk ratio, when the two outcomes are binary.

Usage

lgor_lgrr(r, n1c, n2c, n1t, n2t,
          n12c = min(n1c, n2c),
          n12t = min(n1t, n2t),
          s2c, s2t, f2c, f2t, s1c, s1t, f1t, f1c)

Arguments

r

Correlation coefficient of the two outcomes.

n1c

Number of participants reporting outcome 1 in control group.

n2c

Number of participants reporting outcome 2 in control group.

n1t

Number of participants reporting outcome 1 in treatment group.

n2t

Number of participants reporting outcome 2 in treatment group.

n12c

Number of participants reporting both outcome 1 and outcome 2 in control group. By default, it is equal to the smaller number between n1c and n2c.

n12t

Defined in a similar way as n12c for treatment group.

s2c

Number of participants with event for outcome 2 (dichotomous) in control group.

s2t

Defined in a similar way as s2c for treatment group.

f2c

Number of participants without event for outcome 2 (dichotomous) in control group.

f2t

Defined in a similar way as f2c for treatment group.

s1c

Number of participants with event for outcome 1 (dichotomous) in control group.

s1t

Defined in a similar way as s1c for treatment group.

f1c

Number of participants without event for outcome 1 (dichotomous) in control group.

f1t

Defined in a similar way as f1c for treatment group.

Value

Return the computed covariance.

Author(s)

Min Lu

References

Ahn, S., Lu, M., Lefevor, G.T., Fedewa, A. & Celimli, S. (2016). Application of meta-analysis in sport and exercise science. In N. Ntoumanis, & N. Myers (Eds.), An Introduction to Intermediate and Advanced Statistical Analyses for Sport and Exercise Scientists (pp.233-253). Hoboken, NJ: John Wiley and Sons, Ltd.

Wei, Y., & Higgins, J. (2013). Estimating within study covariances in multivariate meta-analysis with multiple outcomes. Statistics in Medicine, 32(7), 119-1205.

Examples

## simple example
lgor_lgrr(r = 0.71,
          n1c = 30, n2c = 35, n1t = 28, n2t = 32,
          s2c = 5, s2t = 8, f2c = 30, f2t = 24,
          s1c = 5, s1t = 8, f1c = 25, f1t = 20)
## calculate covariances for variable D and DD in Geeganage2010 data
attach(Geeganage2010)
D_DD <- unlist(lapply(1:nrow(Geeganage2010),
              function(i){lgor_lgrr(r = 0.71, n1c = nc_SBP[i], n2c = nc_DD[i],
                 n1t = nt_SBP[i], n2t = nt_DD[i], s2t = st_DD[i], s2c = sc_DD[i],
                 f2c = nc_DD[i] - sc_DD[i], f2t = nt_DD[i] - st_DD[i],
                 s1t = st_D[i], s1c = sc_D[i],
                 f1c = nc_D[i] - sc_D[i], f1t = nt_D[i] - st_D[i])}))
D_DD

luminwin/metavcov documentation built on July 1, 2023, 8:08 p.m.