Appraisal Screening, Diagnosis, Monitoring Studies Flashcards
Describe diagnostic testing
Helps identify the likely cause of an illness in patients presenting with clinical features, and to direct subsequent treatment
Describe screening testing
Used in otherwise healthy individuals to identify those who have an illness that has not yet caused any symptoms or signs
List the types of diagnostic studies and give brief explanation
Screening studies = performed in individuals who do not currently have any symptoms or clinical signs –> unselected target populations (defined by age, gender, or risk factor)
Symptom studies
Signs and elicited symptom studies = symptoms and physical signs assessed, may have different diagnostic value to those spontaneously reported by a patient
Bedside or point of care testing = tests are automated or simple to perform, point of care test
Laboratory test = in labs and hospital, higher degree of skill to perform or interpret
What is accuracy in the context of a diagnostic study?
To determine how well a test performs at ruling in (confirming) or ruling out (excluding) a clinical condition
Result of new test compared w/ that of reference standard
Define STARDS, what is it for/what does it do?
Standard for Reporting of Diagnostic Accuracy (STARD)
a tool used to improve the quality of reporting of studies of diagnostic accuracy
Comprised of a checklist of 25 items and a flow diagram
Summarise the points/sections of the STARD checklist
Title/abstract
Introduction
Methods = participants, test methods, statistical methods
Results = participants, test results, estimates
Discussion
What would be define as an ideal clinical test?
An ideal clinical test is never positive in a patient who is disease free and is never negative in a patient who is in fact disease
Considering test performance parameters, what is a true positive?
patient has the disease and the test is positive
Considering test performance parameters, what is a false positive?
The patient does not have the disease but the test is positive
Considering test performance parameters, what is a true negative?
patient does not have the disease and the test is negative
Considering test performance parameters, what is a false negative?
The patient has the disease but the test is negative
What is sensitivity in the context of screening/diagnostic tests?
Proportion of people with disease who will have a positive test
ability to correctly identify those with disease
What is specificity in the context of screening/diagnostic tests?
proportion of people without disease who will have a negative test
ability to correctly identify those without disease
What is positive predictive value in the context of screening/diagnostic tests?
the proportion (probability) of people with a positive test results who actually have the disease
What is negative predictive value in the context of screening/diagnostic tests?
the proportion of people with a negative test results who do not have disease
