[R-meta] [R meta] How to print z score for subgroup analysis

[Michael Dewey]

Dear Cath

It is not quite clear what you want here. When you say z score do you 
mean a z test for the subgroup differences? Since you have three groups 
the test is a chi squared and is labelled Q in the output (13.58 with 2 df).

Michael

On 19/05/2019 23:05, Cath Kids wrote:
> Dear all,
> 
> I have conducted a subgroup analysis using meta in R.
> I used the following command but can't seem to find the z score in the
> output.
> 
>> post_cb2_es.subgroup<-update.meta(post_cb2_es,
> +                              byvar=category,
> +                              comb.random = TRUE,
> +                              comb.fixed = FALSE,
> +                              print.zval = TRUE)
> 
> Could anyone please kindly advise? Thanks a lot!!!
> 
> Regards,
> Joanne
> 
> ============Analysis results========================
> 
> Number of studies combined: k = 18
> 
>                          SMD            95%-CI    t p-value
> Random effects model 0.2441 [ 0.0203; 0.4678] 2.30  0.0343
> Prediction interval         [-0.5915; 1.0797]
> 
> Quantifying heterogeneity:
> tau^2 = 0.1441; H = 1.67 [1.30; 2.15]; I^2 = 64.1% [40.6%; 78.3%]
> 
> Quantifying residual heterogeneity:
> H = 1.20 [1.00; 1.62]; I^2 = 30.2% [0.0%; 61.8%]
> 
> Test of heterogeneity:
>       Q d.f. p-value
>   47.38   17  0.0001
> 
> Results for subgroups (random effects model):
>                           k     SMD            95%-CI     Q  tau^2   I^2
> category = CBM-A on IB   5 -0.1253 [-0.4858; 0.2351]  4.47 0.0465 10.5%
> category = CBM-I on AB   7  0.1314 [-0.1120; 0.3747]  6.46 0.0306  7.1%
> category = CBM-I on MB   6  0.6715 [ 0.2258; 1.1171] 10.58 0.1173 52.7%
> 
> Test for subgroup differences (random effects model):
>                       Q d.f. p-value
> Between groups   13.58    2  0.0011
> 
> Details on meta-analytical method:
> - Inverse variance method
> - Sidik-Jonkman estimator for tau^2
> - Hartung-Knapp adjustment for random effects model
> 
> 	[[alternative HTML version deleted]]
> 
> _______________________________________________
> R-sig-meta-analysis mailing list
> R-sig-meta-analysis using r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-meta-analysis
> 
> ---
> This email has been checked for viruses by AVG.
> https://www.avg.com
> 
> 

-- 
Michael
http://www.dewey.myzen.co.uk/home.html