Transcript Data Interpretation & Biostatistics

African-American HIV University
Prof. Jeffrey D. Klausner
Division of Infectious Diseases: Global Health
Department of Medicine
UCLA
August 10, 2015
To enhance students ability to interpret data in
charts and graphs
To discuss basic concepts in epidemiology and
science
Gonorrhea global prevalence and reported drug resistance
Sean A. Buono et al. J. Antimicrob. Chemother.
2015;70:374-381
© The Author 2014. Published by Oxford University Press on behalf of the British Society for
Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail:
[email protected]
Survival analysis by cryptococcal antigen test result, Multicenter AIDS Cohort and the
Women's Interagency HIV Study, 1986–2012.
Jennie McKenney et al. Clin Infect Dis. 2015;60:959-965
© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases
Society of America. All rights reserved. For Permissions, please e-mail:
[email protected].
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Sensitivity is the ability of a test to detect a
positive result in those with a disease or
condition
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Specificity is the ability of a test to detect a
negative result in those without a disease or
condition
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Positive Predictive Value (PPV) is the likelihood
that when a test is positive, the patient has the
disease/ condition

Negative Predictive Value (NPV) is the
likelihood that when a test is positive, the
patient has the disease/ condition
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The P-value is the probability that a finding is
due to chance
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When the P-value is less than 0.05 (5%),
scientists call that “statistically significant”
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Statistical significance is when a finding is
unlikely to be due to chance
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Positive predictive value
P-value
Sensitivity
Negative predictive value
Specificity
Significance
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Disease+, test+
Test+, disease+
Chance
Disease-, testTest-, diseaseProbability