Exam 1 - Lecture 3 EBP in Assessment and Diagnosis Flashcards
Define Assessment
Process of identifying the signs and symptoms of a disease or condition and recording the associated data for the purposes of diagnosis
Define Diagnosis
Process of determining the cause of a disease or condition through evaluation of a patient’s history, physical exam, and results of laboratory tests and imaging
Collecting information about nature of an injury. Assessment or Diagnosis?
Assessment
A healthcare practitioner performs a physical exam on an injured leg. Assessment or Diagnosis?
Assessment
Xray taken of injured leg. Assessment or Diagnosis?
Assessment
Clinician determines leg is fractures in two places. Assessment or Diagnosis?
Diagnosis
What is a Reference Standard Test?
The gold standard which all diagnostic procedures are compared because it has been shown to be the most accurate
Newly develop diagnostic tests do what three things during testing?
Compared side by side to gold standard
Conducted on patients know to have the disease, AND
Conducted on patients known to NOT have the disease
What are the 4 parameters/questions in evaluating the Validity of a diagnostic test?
- Diagnostic dilemma?
- Compare test to appropriate, independent reference standard?
- Blinding those interpreting the test and reference standard?
- Apply same reference standard to all PTs with dz regardless of results?
What are the determining Accuracy factors?
Sensitivity, Specificity, PPV, and NPV
Define Sensitivity for a test
Test is positive when patient has the disease or condition
Define Specificity for a test
Test is negative when patient does not have disease or condition
When test is positive and PT does have disease which measure?
Sensitivity
When test is negative and PT does not have disease or condition which measure?
Specificity
True Positive is when what two things are positive or negative?
Test positive, disease positive
False Positive is when what two things are positive or negative?
Test positive, disease negative
False Negative is when what two things are positive or negative?
Test negative, disease positive
True Negative is when what two things are positive or negative?
Test negative, disease negative
What is Sensitivity formula?
a/(a+c)
a=patients who tested positive and who have condition
c=patients who test negative and who have the condition
What is Specificity formula?
d/(b+d)
b=patients who tested positive and do not have condition
d=patients who tested negative and do not have condition
Define Positive Predictive Value (PPV)?
Percentage of patients with a positive test who actually have the disease
Define Negative Predictive Value (NPV)?
Percentage of patients with a negative test who do not have the disease
What is PPV formula?
a/(a+b)
a=patients who tested positive and have the condition
b=patients who do tested positive and do not have the condition
What is NPV formula?
d/(c+d)
c=patients who tested negative and have the condition
d=patients who tested negative and do not have condition
Define Prevalence
Proportion of individuals in a population having a disease or characteristic. EX: water in the bathrub
Define Incidence
Number of new cases that develop in a given period of time. Can die, can be cured, or can be prevented. EX: Water going into tub from spout
What happens to PPV and NPV as prevalence of a disease in sample increases?
PPV increases
NPV decreases
What happens to Prevalence if PT dies, cured, or prevented from disease?
Die=prevalence down
Cured=prevalence down
Prevented=prevalence up
What does a low Sensitivity mean for a test?
Not a good test
Why is it better to have a higher Sensitivity than Specificity?
Higher sensitivity to ensure that PTs who have the disease aren’t missed
What happens to Specificity as Sensitivity increases
Increased sensitivity=decreases specificity.
