meta.ave.prop2 {vcmeta}

Confidence interval for an average proportion difference in 2-group studies

Description

Computes the estimate, standard error, and confidence interval for an average proportion difference from two or more studies.

Usage

meta.ave.prop2(alpha, f1, f2, n1, n2, bystudy = TRUE)

Arguments

alpha

alpha level for 1-alpha confidence

f1

vector of group 1 frequency counts

f2

vector of group 2 frequency counts

n1

vector of group 1 sample sizes

n2

vector of group 2 sample sizes

bystudy

logical to also return each study estimate (TRUE) or not

Value

Returns a matrix. The first row is the average estimate across all studies. If bystudy is TRUE, there is 1 additional row for each study. The matrix has the following columns:

• Estimate - estimated effect size

• SE - standard error

• LL - lower limit of the confidence interval

• UL - upper limit of the confidence interval

References

Bonett DG, Price RM (2014). “Meta-analysis methods for risk differences.” British Journal of Mathematical and Statistical Psychology, 67(3), 371–387. ISSN 00071102, doi:10.1111/bmsp.12024.

Examples

n1 <- c(204, 201, 932, 130, 77)
n2 <- c(106, 103, 415, 132, 83)
f1 <- c(24, 40, 93, 14, 5)
f2 <- c(12, 9, 28, 3, 1)
meta.ave.prop2(.05, f1, f2, n1, n2, bystudy = TRUE)

# Should return:
#             Estimate         SE            LL         UL
# Average 0.0567907589 0.01441216  2.854345e-02 0.08503807
# Study 1 0.0009888529 0.03870413 -7.486985e-02 0.07684756
# Study 2 0.1067323481 0.04018243  2.797623e-02 0.18548847
# Study 3 0.0310980338 0.01587717 -2.064379e-05 0.06221671
# Study 4 0.0837856174 0.03129171  2.245499e-02 0.14511624
# Study 5 0.0524199553 0.03403926 -1.429577e-02 0.11913568