Table 3.
Summary of all the meta-analysis results, grouped by domains
| Domain & Comparison | Excluded Studies | Number of Studies | Effect Size Summary | 95% CI | Z value | p-value for Z | Q—Test for Heterogeneity | p- value for Q | τ2 estimated amount of total heterogeneity | Influence Test | Regression Test for Funnel Plot Asymmetry | Rank Correlation Test for Funnel Plot Asymmetry (Kendall's tau) | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Memory | |||||||||||||
| Delayed recall | 24 | -0,13 * | -0,23 | -0,02 | -2,41 | 0,02* | 56,3 | 0,00 | 0,04 (SE = 0,02) | none | z = -0,09, p = 0,93 | tau = -0,01, p = 0,98 | |
|
Delayed recall: DBS vs. ODT |
5 | -0,40 * | -0,75 | -0,05 | -2,23 | 0,02 * | 8,85 | 0,06 | 0,08 (SE = 0,11) | (Zangaglia et al., 2009; You et al., 2020) | z = 1,13, p = 0,26 | tau = 0,40, p = 0,48 | |
| Backward Digit Span | 9 | 0,11 | -0,02 | 0,23 | 1,70 | 0,09 | 6,07 | 0,64 | 0 (SE = 0,01) | Yamanaka et al. (2012) | z = 0,88, p = 0,37 | tau = 0,22, p = 0,48 | |
| Immediate Recall | 16 | -0,06 | -0,21 | 0,09 | -0,74 | 0,45 | 45,42 | 0,00 | 0,06 (SE = 0,03) | none | z = -0,62, p = 0,53 | Tau = 0,0, p = 1,0 | |
| Executive Function and Attention | |||||||||||||
| Phonemic fluency STN | 31 | -0,42* | -0,51 | -0,33 | -8,96 | < 0,0001 * | 83,08 | 0,00 | 0,0323 (SE = 0,01) | Klempírová et al. (2007) | z = -2,76, p = 0,01 | tau = -0,15, p = 0,24 | |
| Phonemic fluency STN | Moretti et al. (2003) | 30 | -0,40 * | -0,49 | -0,32 | -9,21 | < 0,0001 * | 63,29 | 0,00 | 0,0258 (SE = 0,01) | none | z = -1,19, p = 0,24 | tau = -0,09, p = 0,48 |
| Phonemic fluency GPi | 6 | -0,30* | -0,55 | -0,04 | -2,30 | 0,02 * | 16,03 | 0,01 | 0,0719 (SE = 0,06) | Pillon et al. (2000) | z = 1,49, p = 0,14 | tau = 0,47, p = 0,27 | |
|
Phonemic fluency: DBS vs. ODT |
8 | -0,56 * | -0,79 | -0,33 | -4.83 | < 0,0001 * | 8,64 | 0,28 | 0,0230 (SE = 0,05) | none | z = 1,15, p = 0,26 | tau = 0,28, p = 0,40 | |
| Stroop Color and Word STN | 21 | -0,30 * | -0,39 | -0,22 | -6,9 | < 0,0001 * | 32,87 | 0,03 | 0,0144 (SE = 0,01) | none | z = -2,3, p = 0,02 | tau = -0,12, p = 0,49 | |
| Publication bias assessed by trim and fill | 26 | -0,26 * | -0,34 | -0,18 | -6,32 | < 0,0001 * | 42,13 | 0,02 | 0,0149 (SE = 0,01) | Estimated number of missing studies on the right side: 5 (SE = 3.05) | |||
| Stroop Color and Word GPi | 6 | -0,16 | -0,38 | 0,05 | -1,49 | 0,13 | 17,18 | 0,00 | 0,0444 (SE = 0,04) | none | z = 0,42, p = 0,68 | tau = 0,2, p = 0,72 | |
|
Stroop Color and Word: DBS vs. ODT |
5 | -0,45 * | -0,74 | -0,15 | -2,97 | 0,00 * | 6,84 | 0,14 | 0,0317 (SE = 0,07) | none | z = -0,59, p = 0,54 | tau = -0,20, p = 0,82 | |
| Language | |||||||||||||
| Semantic fluency STN | 28 | -0,48* | -0,55 | -0,41 | -12,9 | < 0,0001 * | 46,6 | 0,01 | 0,0137 (SE = 0,01) | none | z = -1,23, p = 0,21 | tau = -0,05, p = 0,68 | |
| Semantic fluency GPi | 6 | -0,50* | -0,59 | -0,40 | -9,94 | < 0,0001 * | 6,82 | 0,23 | 0,0000 (SE = 0,01) | Follett et al. (2010) | z = 0,21, p = 0,83 | tau = -0,07, p = 1,00 | |
|
Semantic fluency: DBS vs. ODT |
7 | -0,49 * | -0,70 | -0,27 | -4,35 | < 0,0001 * | 3,16 | 0,79 | 0,0000 (SE = 0,05) | none | z = 0,45, p = 0,65 | tau = 0,24, p = 0,56 | |
| General emotional state | |||||||||||||
| Depression STN | 27 | 0,34 * | 0,04 | 0,65 | 2,22 | 0,02* | 462,1 | 0,00 | 0,6172 (SE = 0,18) | Schuepbach et al. (2013) | z = 0,69, p = 0,48 | tau = -0,02, p = 0,93 | |
| Depression STN | Schuepbach et al., 2013) | 26 | 0,21* | 0,07 | 0,34 | 3,04 | 0,002* | 153,7 | 0,00 | 0,0936 (SE = 0,04) | none | z = -0,1, p = 0,9 | tau = -0,08, p = 0,57 |
| Depression GPi | 4 | 0,11 * | 0,01 | 0,21 | 2,22 | 0,03 * | 4,79 | 0,19 | 0,0000 (SE = 0,01) | (Follett et al., 2010; Boel et al., 2016) | z = 2,04, p = 0,04 | tau = 0,66, p = 0,33 | |
| Publication bias assessed by trim and fill | 5 | 0,10 * | -0,00 | 0,19 | 1,96 | 0,050* | 7,18 | 0,13 | 0,0000 (SE = 0,01) | Estimated number of missing studies on the left side: 1 (SE = 1,5779) | |||
| Anxiety STN | 10 | 0,30 * | 0,10 | 0,50 | 3,00 | 0,01 * | 30,04 | 0,00 | 0,0691 (SE = 0,05) | Tang et al. (2015) | z = 0,87, p = 0,38 | tau = 0,20, p = 0,48 | |
When the publication bias tests revealed significant asymmetry the trim and fill assessment results were reported immediately below the original analysis
Articles were excluded when they were identified as outliers, but for transparency, we present all the results (with and without the excluded papers)
* indicates the statistical significand SMDs