18 results
Important Biostatistics and Epidemiology Equations

Sensitivity = TP / (TP + FN) = true positives / disease
Epidemiology Equations Sensitivity ... Specificity Sensitivity ... Biostatistics #statistics ... #specificity #PPV ... #NPV
Sensitivity is the proportion of truly diseased persons in the screened population who are identified as
Sensitivity is the ... PositivePredictiveValue #NegativePredictiveValue ... Calculation #Table #PPV ... #NPV #Formulas ... #Statistics #Matrix
Negative Predictive Value Calculation - Probability that someone with a negative test truly does not have
Negatives #NegativePredictiveValue ... #NPV #Biostatistics ... #statistics #Epidemiology
What's in a Blood Gas? VBG vs ABG

BOTTOM LINE: VBG is less painful, more easily obtained
45mmHg has a 100% sensitivity ... & 100% NPV in predicting
USMLE Epidemiology and Biostatistics Summary
Meta-Analysis: pools data from several studies (greater power), limited by quality/bias of
PPV: proportion ... prevalence is low, then PPV ... NPV: proportion ... specificity -> higher PPV ... -> higher NPV
Pap Smear Algorithm 
#Diagnosis #Pap #Smear #Test #Cervical #HPV #Screening #PrimaryCare #Management #Vaccination #Gynecology
Pap Smear Algorithm ... Test #Cervical #HPV
Genital Ulcer - Differential Algorithm
Painful
 - H. ducreyi (Chancroid)
 - HSV
Painless
 - T pallidum (Chancre)
 -
- Differential Algorithm ... Chlaymydia - HPV ... #Differential #Algorithm
1,3-Beta-D-Glucan and Galactomannan Testing Sensitivity Specificity and False Positives
1,3-Beta-D-Glucan
 • Cell wall component of many fungi
Galactomannan Testing Sensitivity ... dx of IA PPV ... NPV >90% (In most ... invasive dz • Sensitivity ... FalsePositives #Laboratory #sensitivity
Oral Cavity Lesions in a patient with HIV/AIDS
White plaque
 - Pseudo-membranous candidiasis
 - Oral hairy leukoplakia
Mass - Wart (HPV ... Differential #Diagnosis #Algorithm
Positive Predictive Value Calculation - Probability that someone with a positive test actually has the disease

Positive
PositivePredictiveValue #PPV ... Biostatistics #statistics