Table 4.
GRADEpro summary: DBS in Parkinson's disease
| Certainty assessment | N° of patients | Effect | Certainty | |||||
|---|---|---|---|---|---|---|---|---|
| № of studies | Study design | Risk of bias | Inconsistency | Indirectness | Imprecision | (95% CI) | ||
| Delayed Recall STN & GPi DBS (follow up: range 1 years to 3 years) | ||||||||
| 24 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 1429 |
SMD 0.13 SD lower (0.23 lower to 0.02 lower) |
⨁⨁◯◯ LOW |
| Backward Digit Span STN & GPi DBS (follow up: range 1 years to 3 years) | ||||||||
| 9 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 156 |
SMD 0.11 SD higher (0.02 lower to 0.23 higher) |
⨁⨁◯◯ LOW |
| Immediate Recall STN & GPi DBS (follow up: range 1 years to 3 years) | ||||||||
| 16 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 720 |
SMD 0.06 SD lower (0.21 lower to 0.09 higher) |
⨁⨁◯◯ LOW |
| Phonemic fluency STN DBS (follow up: range 1 years to 3 years) | ||||||||
| 30 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 1308 |
SMD 0.4 SD lower (0.49 lower to 0.32 lower) |
⨁⨁◯◯ LOW |
| Phonemic fluency GPi DBS (follow up: range 1 years to 3 years) | ||||||||
| 6 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 304 |
SMD 0.3 SD lower (0.55 lower to 0.04 higher) |
⨁⨁◯◯ LOW |
| Stroop Color and Word STN DBS (follow up: range 1 years to 3 years) | ||||||||
| 21 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 958 |
SMD 0.3 SD lower (0.39 lower to 0.22 lower) |
⨁⨁◯◯ LOW |
| Stroop Color and Word GPi DBS (follow up: range 1 years to 3 years) | ||||||||
| 6 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 304 |
SMD 0.16 SD lower (0.38 lower to 0.05 higher) |
⨁⨁◯◯ LOW |
| Semantic Fluency STN DBS (follow up: range 1 years to 3 years) | ||||||||
| 28 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 1378 |
SMD 0.49 SD lower (0.57 lower to 0.41 lower) |
⨁⨁◯◯ LOW |
| Semantic Fluency GPi DBS (follow up: range 1 years to 3 years) | ||||||||
| 6 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 304 |
SMD 0.5 SD lower (0.59 lower to 0.4 lower) |
⨁⨁◯◯ LOW |
| Depression STN DBS (follow up: range 1 years to 3 years) | ||||||||
| 26 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 1261 |
SMD 0.2 SD higher (0.04 higher to 0.36 higher) |
⨁⨁◯◯ LOW |
| Depression GPi DBS (follow up: range 1 years to 3 years) | ||||||||
| 4 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | serious a | 231 |
SMD 0.11 SD higher (0.01 higher to 0.21 higher) |
⨁◯◯◯ VERY LOW |
| Anxiety STN DBS (follow up: range 1 years to 3 years) | ||||||||
| 10 |
observational studies between (DBS vs. ODT) within (pre vs. post) |
not serious | not serious | not serious | not serious | 290 |
SMD 0.3 SD higher (0.1 higher to 0.5 higher) |
⨁⨁◯◯ LOW |
CI Confidence interval, SMD Standardized mean difference (Hedges’g), STN subthalamic nucleus, GPi globus pallidus pars interna, DBS deep brain stimulation, ODT optimal drug therapy (control group)
GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect
Moderate quality: The authors believe that the true effect is probably close to the estimated effect
Low quality: Further research is very likely to have an important impact on our confidence in the estimated effect and could change the estimate
Very low quality: We are very uncertain about the estimate
Explanations
aA very small number of included studies