A diagnostic [[accuracy]] study is a type of clinical research designed to evaluate how well a diagnostic test correctly identifies or excludes a particular disease or condition, by comparing it to a reference standard (also called the "gold standard").

🔍 Key Characteristics
Index Test: The test being evaluated (e.g., SWI or GRE-T2* in the study).

Reference Standard: The best available method to determine the true disease status (e.g., CE-T1 imaging).

Outcomes Measured:

Sensitivity: Ability to correctly identify patients with the condition.

Specificity: Ability to correctly identify patients without the condition.

Positive Predictive Value (PPV) / Negative Predictive Value (NPV)

Interrater agreement (e.g., Kappa statistic)

🧪 Purpose
To determine whether a diagnostic test is accurate enough to:

Replace an existing test

Be used as a screening tool

Avoid unnecessary invasive or costly procedures