tailieunhanh - Ebook Observer performance methods for diagnostic imaging: Part 2

Part 2 book “Observer performance methods for diagnostic imaging” has contents: Empirical operating characteristics possible with FROC data, computation and meanings of empirical FROC FOM-statistics and AUC measures, visual search paradigms, analyzing FROC data, and other contents. | PART C The free-response ROC (FROC) paradigm 12 The FROC paradigm Introduction Until now focus has been on the receiver operating characteristic (ROC) paradigm. For diffuse interstitial lung disease,* and diseases like it, where disease location is implicit (by definition diffuse interstitial lung disease is spread through and confined to lung tissues) this is an appropriate paradigm in the sense that possibly essential information is not being lost by limiting the radiologist’s response in the ROC study to a single rating. The extent of the disease, that is, how far it has spread within the lungs, is an example of essential information that is still Anytime essential information is not accounted for in the analysis, as a physicist, the author sees a red flag. There is room for improvement in basic ROC methodology by modifying it to account for extent of disease. However, this is not the direction taken in this book. Instead, the direction taken is accounting for location of disease. In clinical practice it is not only important to identify whether the patient is diseased, but also to offer further guidance to subsequent care-givers regarding other characteristics (such as location, size, extent) of the disease. In most clinical tasks if the radiologist believes the patient may be diseased, there is a location (or more than one location) associated with the manifestation of the suspected disease. Physicians have a term for this: focal disease, defined as a disease located at a specific and distinct area. For focal disease, the ROC paradigm restricts the collected information to a single rating representing the confidence level that there is disease somewhere in the patient’s imaged anatomy. The emphasis on somewhere is because it begs the question: if the radiologist believes the disease is somewhere, why not have them to point to it? In fact, they do point to it in the sense that they record the location(s) of suspect regions in their clinical .

• Y khoa - Dược
• Observer performance methods
• Diagnostic imaging
• Empirical operating characteristics possible
• Computation and meanings
• Visual search paradigms