Uncertainty and agreement in the management of unruptured intracranial aneurysms

J Neurosurg. 2014 Mar;120(3):618-23. doi: 10.3171/2013.11.JNS131366. Epub 2014 Jan 3.


Object: The management of unruptured intracranial aneurysms remains controversial. The goal of this study was to evaluate the clinical community agreement in decision making regarding unruptured intracranial aneurysms.

Methods: A portfolio of 41 cases of unruptured intracranial aneurysms with angiographic images, along with a short description of the patient presentation, was sent to 28 clinicians (16 radiologists and 12 surgeons) with varying years of experience in the management of unruptured intracranial aneurysms. Five senior clinicians responded twice at least 3 months apart. Nineteen cases (46%) were selected from patients recruited in the Canadian UnRuptured Endovascular versus Surgery trial, an ongoing randomized comparison of coil embolization and clip placement. For each case, the responder was to first choose between 3 treatment options (observation, surgical clip placement, or endovascular coil embolization) and then indicate their level of certainty on a quantitative 0-10 scale. Agreement in decision making was studied using κ statistics.

Results: Decisions to coil were more frequent (n = 612, 53%) than decisions to clip (n = 289, 25%) or to observe (n = 259, 22%). Interjudge agreement was only fair (κ = 0.31 ± 0.02) for all cases and all judges, despite substantial intrajudge agreement (range 0.44-0.83 ± 0.10), with high mean individual certainty levels for each case (range 6.5-9.4 ± 2.0 on a scale of 0-10). Agreement was no better within specialties (surgeons or radiologists), within capability groups (those able to perform endovascular coiling alone, surgical clipping alone, or both), or with more experience. There was no correlation between certainty levels and years of experience. Agreement was lower when the cases were taken from the randomized trial (κ = 0.19 ± 0.2) compared with nontrial cases (κ = 0.35 ± 0.2).

Conclusions: Individuals do not agree regarding the management of unruptured intracranial aneurysms, even when they share a background in the same specialty, similar capabilities in aneurysm management, or years of practice. If community equipoise is a necessary precondition for trial participation, this study has found sufficient uncertainty and disagreement among clinicians to justify randomized trials.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Attitude of Health Personnel*
  • Cerebral Angiography / statistics & numerical data
  • Embolization, Therapeutic*
  • Female
  • Humans
  • Intracranial Aneurysm* / diagnostic imaging
  • Intracranial Aneurysm* / surgery
  • Intracranial Aneurysm* / therapy
  • Male
  • Middle Aged
  • Neurosurgery*
  • Observer Variation
  • Physicians / psychology*
  • Radiology*
  • Tomography, X-Ray Computed / statistics & numerical data
  • Uncertainty