Rationale and objectives: Patient-centered outcome measures have become an essential focus in research methodology in recent years. This may be particularly challenging in imaging research at the technology assessment level to incorporate patient-centeredness. A primary issue in this field is designing a reference standard that is applicable to the entire study population.
Materials and methods: This important element is necessary for translation of findings into clinical practice. In our work, computed tomographic perfusion imaging is being evaluated as a new technology used in aneurysmal subarachnoid hemorrhage patients to detect cerebral vasospasm. We have developed a new reference standard employing a multistage hierarchical design incorporating both clinical and imaging criteria to determine a diagnosis of vasospasm.
Results: A flowchart of the reference standard levels is provided for illustration. The limitations and potential biases that may occur using this reference standard are discussed.
Conclusions: This reference standard will be applicable to the entire study population, including those with and without symptoms or further imaging with digital subtraction angiography.