Evidence
This page contains a snapshot of featured content which highlights evidence addressing key clinical questions including areas of uncertainty. Please see the main topic reference list for details of all sources underpinning this topic.
BMJ Best Practice evidence tables
Evidence tables provide easily navigated layers of evidence in the context of specific clinical questions, using GRADE and a BMJ Best Practice Effectiveness rating. Follow the links at the bottom of the table, which go to the related evidence score in the main topic text, providing additional context for the clinical question. Find out more about our evidence tables.
This table is a summary of the analysis reported in a Cochrane Clinical Answer that focuses on the above important clinical question.
Confidence in the evidence is moderate or low to moderate where GRADE has been performed and the intervention may be more effective/beneficial than the comparison for key outcomes.
Population: People with subarachnoid haemorrhage from a ruptured aneurysm (mean age 55 years; range 14-87 years)
Intervention: Endovascular coil
Comparison: Neurosurgical clipping
| Outcome | Effectiveness (BMJ rating)? | Confidence in evidence (GRADE)? |
|---|---|---|
Death or dependence in activities of daily living (ADL) at 12 months ᵃ | Favours intervention | Moderate |
Death or dependence in ADL at 10 years ᵃ | Favours intervention | Low |
Delayed cerebral ischaemia (DCI; 2-3 months) | Favours intervention | Moderate |
Rebleeding post‐procedure within 1 year ᵇ | Favours comparison | High |
Rebleeding post‐procedure within 10 years ᵇ | Favours comparison | Low |
Degree of obliteration (at 1 year): non‐complete (<100%) obliteration | Favours comparison | GRADE assessment not performed for this outcome |
Degree of obliteration (at 1 year): <90% occlusion | No statistically significant difference | GRADE assessment not performed for this outcome |
All‐cause mortality within 1 year ᶜ | No statistically significant difference | Moderate |
All‐cause mortality within 10 years ᶜ | Favours intervention | GRADE assessment not performed for this outcome |
Complications | No statistically significant difference | Low |
Quality of life | - | None of the included studies reported this outcome |
Note The overall evidence rating in this table is based upon the sole primary outcome as listed in the Cochrane review which this content is based upon (death or dependence in daily activities). The Cochrane review which this Cochrane Clinical Answer (CCA) is based upon notes that the included population were mostly people with less severe subarachnoid haemorrhage (e.g., World Federation of Neurological Surgeons grade I or II). It also noted that only simple endovascular coiling was evaluated due to the lack of evidence for more complex procedures such as balloon or stent-assisted coiling. ᵃ The CCA notes that endovascular coiling was favoured for death or dependence in activities of daily living at 2 to 3 months, but that there was no statistically significant difference between treatment groups at 5 years. The reviewers did not perform a GRADE assessment of evidence quality at either time point. Dependence in activities of daily living was defined as modified Rankin scale 3 to 5 or Glasgow Outcome Scale 2 to 3. ᵇ The CCA notes that the rates of rebleeding were low in both groups. There was no statistically significant difference between treatment groups for rebleeding post-procedure within 3 months, but neurosurgical clipping was favoured within 5 years. The reviewers did not perform a GRADE assessment of evidence quality at either time point. ᶜ The CCA notes that endovascular coiling was favoured for all-cause mortality within 5 years, but that there was no statistically significant difference between treatment groups within 2 to 3 months. The reviewers did not perform a GRADE assessment of evidence quality for either of these time points.
This evidence table is related to the following section/s:
Cochrane Clinical Answers
Cochrane Clinical Answers (CCAs) provide a readable, digestible, clinically focused entry point to rigorous research from Cochrane systematic reviews. They are designed to be actionable and to inform decision making at the point of care and have been added to relevant sections of the main Best Practice text.
- How does endovascular coiling compare with neurosurgical clipping for people with aneurysmal subarachnoid hemorrhage (SAH)?
- What are the effects of endothelin receptor antagonists for people with subarachnoid hemorrhage?
Use of this content is subject to our disclaimer