dat.lopez2019: Studies on the Effectiveness of CBT for Depression

dat.lopez2019R Documentation

Studies on the Effectiveness of CBT for Depression

Description

Results from 76 studies examining the effectiveness of cognitive behavioral therapy (CBT) for depression in adults.

Usage

dat.lopez2019

Format

The data frame contains the following columns:

study character (first) author and year of study
treatment character treatment provided (see ‘Details’)
scale character scale used to measure depression symptoms
n numeric group size
diff numeric standardized mean change
se numeric corresponding standard error
group numeric type of therapy (0 = individual, 1 = group therapy)
tailored numeric whether the intervention was tailored to each patient (0 = no, 1 = yes)
sessions numeric number of sessions
length numeric average session length (in minutes)
intensity numeric product of sessions and length
multi numeric intervention included multimedia elements (0 = no, 1 = yes)
cog numeric intervention included cognitive techniques (0 = no, 1 = yes)
ba numeric intervention included behavioral activation (0 = no, 1 = yes)
psed numeric intervention included psychoeducation (0 = no, 1 = yes)
home numeric intervention included homework (0 = no, 1 = yes)
prob numeric intervention included problem solving (0 = no, 1 = yes)
soc numeric intervention included social skills training (0 = no, 1 = yes)
relax numeric intervention included relaxation (0 = no, 1 = yes)
goal numeric intervention included goal setting (0 = no, 1 = yes)
final numeric intervention included a final session (0 = no, 1 = yes)
mind numeric intervention included mindfulness (0 = no, 1 = yes)
act numeric intervention included acceptance and commitment therapy (0 = no, 1 = yes)

Details

The dataset includes the results from 76 studies examining the effectiveness of cognitive behavioral therapy (CBT) for treating depression in adults. Studies included two or more of the following treatments/conditions:

  1. treatment as usual (TAU),

  2. no treatment,

  3. wait list,

  4. psychological or attention placebo,

  5. face-to-face CBT,

  6. multimedia CBT,

  7. hybrid CBT (i.e., multimedia CBT with one or more face-to-face sessions).

Multimedia CBT was defined as CBT delivered via self-help books, audio/video recordings, telephone, computer programs, apps, e-mail, or text messages.

Variable diff is the standardized mean change within each group, with negative values indicating a decrease in depression symptoms.

Concepts

psychiatry, standardized mean changes, network meta-analysis

Author(s)

Wolfgang Viechtbauer, wvb@metafor-project.org, https://www.metafor-project.org

Source

Personal communication.

References

López-López, J. A., Davies, S. R., Caldwell, D. M., Churchill, R., Peters, T. J., Tallon, D., Dawson, S., Wu, Q., Li, J., Taylor, A., Lewis, G., Kessler, D. S., Wiles, N., & Welton, N. J. (2019). The process and delivery of CBT for depression in adults: A systematic review and network meta-analysis. Psychological Medicine, 49(12), 1937–1947. https://doi.org/10.1017/S003329171900120X

Examples

### copy data into 'dat' and examine data
dat <- dat.lopez2019
dat[1:10,1:6]

## Not run: 

### load metafor package
library(metafor)

### create network graph ('igraph' package must be installed)
library(igraph, warn.conflicts=FALSE)
pairs <- data.frame(do.call(rbind,
   sapply(split(dat$treatment, dat$study), function(x) t(combn(x,2)))), stringsAsFactors=FALSE)
pairs$X1 <- factor(pairs$X1, levels=sort(unique(dat$treatment)))
pairs$X2 <- factor(pairs$X2, levels=sort(unique(dat$treatment)))
tab <- table(pairs[,1], pairs[,2])
tab # adjacency matrix
g <- graph_from_adjacency_matrix(tab, mode = "plus", weighted=TRUE, diag=FALSE)
plot(g, edge.curved=FALSE, edge.width=E(g)$weight/2,
     layout=layout_in_circle(g, order=c("Wait list", "No treatment", "TAU", "Multimedia CBT",
                                        "Hybrid CBT", "F2F CBT", "Placebo")),
     vertex.size=45, vertex.color="lightgray", vertex.label.color="black", vertex.label.font=2)

### restructure data into wide format
dat <- to.wide(dat, study="study", grp="treatment", ref="TAU",
               grpvars=c("diff","se","n"), postfix=c("1","2"))

### compute contrasts between treatment pairs and corresponding sampling variances
dat$yi <- with(dat, diff1 - diff2)
dat$vi <- with(dat, se1^2 + se2^2)

### calculate the variance-covariance matrix for multitreatment studies
calc.v <- function(x) {
   v <- matrix(x$se2[1]^2, nrow=nrow(x), ncol=nrow(x))
   diag(v) <- x$vi
   v
}
V <- bldiag(lapply(split(dat, dat$study), calc.v))

### add contrast matrix to the dataset
dat <- contrmat(dat, grp1="treatment1", grp2="treatment2")

### network meta-analysis using a contrast-based random-effects model
### by setting rho=1/2, tau^2 reflects the amount of heterogeneity for all treatment comparisons
### the treatment left out (TAU) becomes the reference level for the treatment comparisons
res <- rma.mv(yi, V, data=dat,
         mods = ~ No.treatment + Wait.list + Placebo + F2F.CBT + Hybrid.CBT + Multimedia.CBT - 1,
         random = ~ comp | study, rho=1/2)
res

### forest plot of the contrast estimates (treatments versus TAU)
forest(coef(res), diag(vcov(res)), slab=sub(".", " ", names(coef(res)), fixed=TRUE),
       xlim=c(-5,5), alim=c(-3,3), psize=1, header="Treatment",
       xlab="Difference in Standardized Mean Change (compared to TAU)")

### fit random inconsistency effects model
res <- rma.mv(yi, V, data=dat,
         mods = ~ No.treatment + Wait.list + Placebo + F2F.CBT + Hybrid.CBT + Multimedia.CBT - 1,
         random = list(~ comp | study, ~ comp | design), rho=1/2, phi=1/2)
res


## End(Not run)

metadat documentation built on April 6, 2022, 5:08 p.m.