Week 1 Flashcards
Selectivity
An ongoing decision making process that guides data collection and interpretaion
Hypothetical-deductive approach
The process under which a patient is observed, a hypothesis is made of their condition, data is collected to prove/disprove that hypothesis until a hypothesis is sufficiently proved true, a diagnosis can be made, and treatment can start.
Differential diagnosis
The set of initial hypothesis that a physician may have after interviewing a patient, usually after 6 or 7 initial questions.
ROS
Review of Systems, in which a physician will investigate each of the organ systems
CT
Computed Tomography: a noninvasive medical imaging process using x-rays to model in the inside of a body
ECG
Electrocardiagram, a quick test to check the heart beat of a patient, used to diagnose heart attacks and irregular heart beats call arrhthmias.
Sensitivity vs Specificity
Sensitivity =
* The liklihood that a given datum will be observed in a patient with a given disease/condition.
* The test accuracy index
* How well the test will identify disease with the condition
* detection rate
Specificity =
* How well the test will identify people without the disease/condition
* percent of people without disease that test negative
Sensitivity = Se
Specificity = Sp
Se = 99%
Sp = 95%
Se = d/(b+dā)
Sp = a/(a+c)
Pathognomonic
Tests that immediately prove a diagnosis to be true (ie. Pap smear)
Specificity
An observation is highly specific if it is often not observed in patients who do not have the disease.
A pathognomonic observation is 100% specific for that disease
Prevalence of disease
The proportion of the population of interest that has the disease at any given time.
Baseline rate
Prevelance of disease in a selected population
Accuracy of a test is defined by formula:
Accuracy = (Tp+Tn) / (Tp+Tn+Fp+Fn)
Sensitivity formula
Sensitivity = Tp / Tp+Fn
The ability of a test to correctly identify patients with disease/condition
Specificity formula
Specificity = Sp = Tn / (Tn+Fp)
Ability of a test to correctly determine healthy subjects
Representative heuristic
The degreee in which probabilities are judged based on how A is representative/similar to B
What is the probability that A belongs to class B?
Availability heuristic
An estimate of probability based on the ease of which similar events are recalled.
Anchoring and adjustment heuristic
Where an initial estimate of probability is made and then adjusted with new information.
Prevalence
The frequency of an event in a population
Clinical subgroubs
A well defined subgroup in which disease prevalence is known
Clinical prediction rules
A set of rules that define how clinicians can use clinical findings to estimate probability, from a systematic study of patients who have a specific diagnostic problem.
Referral bias
Disease prevalence in a population that is referred to specialists will occur at a higher rate because they are expected to have a higher likely hood of disease if they are pre screened by the PCP.
