Response to Cassidy and Cote

We thank Drs Cassidy and Cote for their letter in response to our article “Case Misclassification….” It appears as if the methods and impact of our study was misinterpreted and we appreciate the opportunity to offer clarification. Our primary aim was very simple—to determine the positive predictive value (PPV) for identifying cervical artery dissection (CAD) by using the search strategy used in the studies by Rothwell and Cassidy. The earlier studies purport to negate the causal association between cervical manipulative therapy (CMT) and CAD by demonstrating a similar association between visits to primary care physicians (PCPs) before being identified as a “case.” We agree that there is no plausible casual mechanism that would explain an association between PCPs and dissection.
Source: Journal of Stroke and Cerebrovascular Diseases - Category: Neurology Authors: Tags: Letter to the Editor Source Type: research