Related Experiment Video
Updated: Nov 13, 2025

Minimally Invasive Thumb-sized Pterional Craniotomy for Surgical Clip Ligation of Unruptured Anterior Circulation Aneurysms
Published on: August 11, 2015
Unruptured aneurysms: Why observational studies fall short no matter how "Big" the Data
T E Darsaut1, R Fahed2, J Raymond3
1Division of Neurosurgery, Department of Surgery, Mackenzie Health Sciences Center, University of Alberta hospital, 8440 112th Street, Edmonton, T6G 2B7 Alberta, Canada.
Background:
The best management of unruptured intracranial aneurysms (UIAs) remains unknown, despite multiple observational studies. A randomized trial (RCT) is in order. Yet, a National Institute Neurological Disorders and Stroke workshop has once again proposed to use prospective observational studies (POS) of large databases to address such problems.
Methods:
We review the historical misconceptions that have been associated with observations of UIAs and their treatments. We critically examine some recent methods that have been proposed to address shortcomings of observational studies. We finally review the ethical principles underlying the use of trial methods in the care of patients.
Results:
Replacing RCTs with POS submits patients to management options that have never been proven beneficial, while making them involuntary research subjects of studies that are inevitably biased. A science of practice cannot be an outsider's examination of the behavior of clinicians incapable of questioning their practice. The thesis we propose is that a science of practice must not only eventually determine what best practice will be; It must engage agents involved in medical practice to transparently reveal the uncertainty that calls for management options to be offered under the guidance of declared and controlled care research, to optimize patient outcomes in spite of the uncertainty.
Conclusion:
To use POS rather than RCTs in medical practice is to renege on scientific and ethical principles that characterize modern medicine. Instead, we must learn to integrate care research into our practice to provide optimal medical care in real time.
Related Concept Videos
Aneurysm III: Interprofessional Care
Aneurysm II: Clinical Manifestations and Diagnostic Studies
Aneurysm I: Introduction
Observational Studies
There are three types of observational studies – Prospective, retrospective, and cross-sectional.
Prospective Study
Prospective studies, also known as longitudinal or cohort studies, are carried out by collecting future data from groups sharing similar characteristics. One...

