DIAGNOSTIC MICROBIOLOGY
CERTIFICATION EVALUATION COMPLETE
QUESTIONS AND SOLUTIONS GRADED
APLUS
●● Possibility
Answer: Potential for an event to occur; all outcomes with nonzero
chance are possible
●● Probable vs possible
Answer: Possible = can occur; probable = likely based on statistics and
clinical presentation
●● Importance of patient history
Answer: Used to determine what is probable and guide diagnostic
testing
●● True positive
Answer: Patient has disease and test says they have disease
●● True negative
Answer: Patient does not have disease and test says they do not have
disease
, ●● False positive
Answer: Patient does not have disease but test says they do; can cause
psychological, social, or treatment issues
●● False negative
Answer: Patient has disease but test says they don't; may delay treatment
and cause harm
●● Sensitivity
Answer: Percentage of sick patients correctly identified; TP/(TP+FN);
rule OUT disease
●● Specificity
Answer: Percentage of healthy patients correctly identified;
TN/(TN+FP); rule IN disease
●● Sensitivity vs specificity relationship
Answer: Trade-off between the two; depends on disease severity and
consequences of false results
●● High sensitivity test use
Answer: Used when disease is serious, treatable, and cannot be missed
CERTIFICATION EVALUATION COMPLETE
QUESTIONS AND SOLUTIONS GRADED
APLUS
●● Possibility
Answer: Potential for an event to occur; all outcomes with nonzero
chance are possible
●● Probable vs possible
Answer: Possible = can occur; probable = likely based on statistics and
clinical presentation
●● Importance of patient history
Answer: Used to determine what is probable and guide diagnostic
testing
●● True positive
Answer: Patient has disease and test says they have disease
●● True negative
Answer: Patient does not have disease and test says they do not have
disease
, ●● False positive
Answer: Patient does not have disease but test says they do; can cause
psychological, social, or treatment issues
●● False negative
Answer: Patient has disease but test says they don't; may delay treatment
and cause harm
●● Sensitivity
Answer: Percentage of sick patients correctly identified; TP/(TP+FN);
rule OUT disease
●● Specificity
Answer: Percentage of healthy patients correctly identified;
TN/(TN+FP); rule IN disease
●● Sensitivity vs specificity relationship
Answer: Trade-off between the two; depends on disease severity and
consequences of false results
●● High sensitivity test use
Answer: Used when disease is serious, treatable, and cannot be missed
