这种类型的数据称为从属效应大小。可以使用几种方法来处理依赖性。我建议使用三级荟萃分析(Cheung,2014; Konstantopoulos,2011; Van den Noortgate等,2013)。它将变异分解为2级和3级异质性。在您的示例中,级别2和级别3的异质性是指由于子量表和研究而导致的异质性。在R中实现的metaSEM软件包(http://courses.nus.edu.sg/course/psycwlm/Internet/metaSEM/)提供了进行三级荟萃分析的功能。例如,
## Your data
d <- round(rnorm(5,5,1),2)
sd <- round(rnorm(5,1,0.1),2)
study <- c(1,2,3,3,3)
subscore <- c(1,1,1,2,3)
my_data <- as.data.frame(cbind(study, subscore, d, sd))
## Load the library with the data set
library(metaSEM)
summary( meta3(y=d, v=sd^2, cluster=study, data=my_data) )
输出为:
Running Meta analysis with ML
Call:
meta3(y = d, v = sd^2, cluster = study, data = my_data)
95% confidence intervals: z statistic approximation
Coefficients:
Estimate Std.Error lbound ubound z value Pr(>|z|)
Intercept 4.9878e+00 4.2839e-01 4.1482e+00 5.8275e+00 11.643 < 2.2e-16 ***
Tau2_2 1.0000e-10 NA NA NA NA NA
Tau2_3 1.0000e-10 NA NA NA NA NA
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Q statistic on homogeneity of effect sizes: 0.1856967
Degrees of freedom of the Q statistic: 4
P value of the Q statistic: 0.9959473
Heterogeneity indices (based on the estimated Tau2):
Estimate
I2_2 (Typical v: Q statistic) 0
I2_3 (Typical v: Q statistic) 0
Number of studies (or clusters): 3
Number of observed statistics: 5
Number of estimated parameters: 3
Degrees of freedom: 2
-2 log likelihood: 8.989807
OpenMx status1: 1 ("0" and "1": considered fine; other values indicate problems)
在该示例中,级别2和级别3异质性的估计接近于0。级别2和级别3协变量也可以包括在内,以对异质性建模。有关三级荟萃分析的更多示例,请访问http://courses.nus.edu.sg/course/psycwlm/Internet/metaSEM/3level.html。
参考文献
张,MW-L。(2014)。使用三级荟萃分析对依赖效应大小进行建模:一种结构方程式建模方法。心理方法,19(2),211-29。doi:10.1037 / a0032968。
Konstantopoulos,S.(2011年)。三级荟萃分析中的固定效应和方差成分估计。研究综合方法,2(1),61–76。doi:10.1002 / jrsm.35
Van den Noortgate,W.,López-López,JA,Marín-Martínez,F.&Sánchez-Meca,J.(2013)。依赖效应量的三级荟萃分析。行为研究方法,45(2),576–594。doi:10.3758 / s13428-012-0261-6