Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ TEST TAKING TIPS ++ Test Taking Tips Memorize the table below for easy calculation of sensitivity, specificity, and positive and negative predictive values. Know the differences between different types of statistical tests. ++ +++ What is sensitivity? ++ Proportion of truly diseased persons in a screened population who are identified as being diseased by the test. It is a measure of the probability of correctly diagnosing a condition. +++ Sensitivity equation: ++ True positive/(true positive + false negative) +++ What is specificity? ++ The proportion of truly nondiseased persons who are so identified by the screening test +++ Specificity equation: ++ True negative/(false positive + true negative) +++ False-positive rate: ++ 1 – specificity +++ False-negative rate ++ 1 – sensitivity +++ What is positive predictive value? ++ The probability that a person with a positive test result has the disease +++ What is the positive predictive equation? ++ True positive/(true positive + false positive) +++ What is the negative predicted value? ++ The probability that a patient with a negative test result really is free of the disease +++ What is the negative predicted value equation? ++ True negative/(false negative + true negative) +++ Definition of prevalence: ++ The total number of cases of a given disease in a specified population at a designated time +++ Definition of incidence: ++ The number of new cases of a given disease during a given period in a specified population +++ What is the absolute risk reduction? ++ The absolute arithmetic difference in outcome rates between control and experimental patients in a trial +++ What is relative risk reduction? ++ The proportional reduction in outcome rates between control and experimental patients in a trial +++ A range of values that has a specified probability of containing the rate or trend: ++ Confidence intervals +++ A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment: ++ Double-blind method +++ The number of patients who need to be treated to prevent one adverse outcome: ++ Number Needed To Treat +++ The probability that an event will occur: ++ Risk +++ The number of units in a population to be studied: ++ Sample size +... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.