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Biomedical subjects

Cathy M Helgason

Publications and source records attributed to Cathy M Helgason.

2 recordsLinked to original sources

The selection of antithrombotic agents in the prevention of recurrent ischemic stroke.

The scientific selection of antithrombotic therapy has been dominated by group-based interpretation of data in the form of probability-based statistics in evidence-based medicine. Because the data in large randomized trials are grouped and averaged, the relationship to initial conditions of the patient is lost. There is a pathologic model and basis by which antithrombotic agents may be chosen for prevention of recurrent thrombus and thromboembolism in patients with stroke. This model applies in all settings, but has not been tested when the elements of the model remain connected to the individual patient and his or her unique context. Alternative math models and perception-based science respect the criticality of initial conditions and capture the rules that apply to the actual causal mechanisms within the patient's body. Individualized patient rather than group-based choices insure thrombus-type specific targeted therapy.

Brain Ischemia↗

Measurable differences between sequential and parallel diagnostic decision processes for determining stroke subtype: a representation of interacting pathologies.

Stroke diagnosis depends on causal subtype. The accepted classification procedure is a succession of diagnostic tests administered in an order based on prior reported frequencies of the subtypes. The first positive test result completely determines diagnosis. An alternative approach tests multiple concomitant diagnostic hypotheses in parallel. This method permits multiple simultaneous pathologies in the patient. These two diagnostic procedures can be compared by novel numeric criteria presented here. Thrombosis, a type of ischemic stroke, results from interaction between endothelium, blood flow and blood components. We tested for ischemic stroke on thirty patients using both methods. For each patient the procedure produced an assessment of severity as an ordered set of three numbers in the interval [0, 1]. We measured the difference in diagnosis between the sequential and parallel diagnostic algorithms. The computations reveal systematic differences: The sequential procedure tends to under-diagnose and excludes any measure of interaction between pathologic elements.

Algorithms↗