CIC Certification Exam | Complete Infection Prevention and
Control Practice Questions & Detailed Rationales (2026/2027)
Question 1
An infection preventionist is investigating an outbreak of surgical site
infections (SSIs) following cardiac surgeries. Which study design is most
appropriate for a rapid initial evaluation to identify specific risk factors
and exposures among cases versus non-cases?
A. Randomized controlled trial
B. Retrospective case-control study
C. Cross-sectional prevalence survey
D. Prospective cohort study
Correct Answer: B. Retrospective case-control study
Detailed Rationale: A retrospective case-control study compares
patients who developed the infection (cases) with those who
underwent the same procedure without developing infection (controls)
to look backward at exposures and risk factors, making it highly efficient
for acute outbreak investigations.
Question 2
Which of the following measures represents an incidence density rate
used in healthcare-associated infection (HAI) surveillance?
A. Number of central line-associated bloodstream infections divided by
total patient discharges
,B. Number of catheter-associated urinary tract infections divided by
total patient-days × 1,000
C. Number of ventilator-associated events divided by total ventilator-
days × 1,000
D. Total number of surgical site infections divided by total number of
surgical procedures performed
Correct Answer: C. Number of ventilator-associated events divided by
total ventilator-days × 1,000
Detailed Rationale: Incidence density rates use person-time or device-
time (such as ventilator-days or central line-days) in the denominator,
accounting for the varying length of time patients are exposed to
specific risk devices.
Question 3
According to Spaulding’s classification, how must surgical instruments
that enter normally sterile tissue or the vascular system be processed
before reuse?
A. Low-level disinfection
B. Intermediate-level disinfection
C. High-level disinfection
D. Sterilization
Correct Answer: D. Sterilization
Detailed Rationale: Critical items (such as surgical instruments, cardiac
catheters, and implants) enter sterile body tissues or vascular systems
,and must be sterile, as any microbial contamination can result in direct
transmission and severe infection.
Question 4
Which type of airflow is required for an Airborne Infection Isolation
Room (AIIR) housing a patient with suspected pulmonary tuberculosis?
A. Positive pressure with at least 12 air exchanges per hour
B. Negative pressure with at least 6 to 12 air exchanges per hour and air
exhausted directly outdoors or through a HEPA filter
C. Neutral pressure with natural window ventilation
D. Laminar airflow with downward vertical filtration
Correct Answer: B. Negative pressure with at least 6 to 12 air exchanges
per hour and air exhausted directly outdoors or through a HEPA filter
Detailed Rationale: Negative pressure airflow ensures that air flows
into the isolation room when the door is opened rather than leaking out
into clinical corridors, preventing the escape of infectious droplet nuclei.
Question 5
What is the primary mode of transmission for Bordetella pertussis in a
healthcare facility?
A. Airborne droplet nuclei persisting for hours across long distances
B. Large respiratory droplets generated during coughing, sneezing, or
talking
C. Direct percutaneous inoculation via contaminated sharps
D. Fecal-oral contamination from environmental surfaces
, Correct Answer: B. Large respiratory droplets generated during
coughing, sneezing, or talking
Detailed Rationale: Bordetella pertussis is transmitted primarily via
large respiratory droplets that travel short distances (typically 3 feet or
less) and land on mucosal surfaces, requiring Droplet Precautions.
Question 6
Which statistical metric is utilized by the National Healthcare Safety
Network (NHSN) to compare the actual number of reported infections
in a facility to the predicted number based on risk-adjusted national
baseline data?
A. Odds Ratio (OR)
B. Relative Risk (RR)
C. Standardized Infection Ratio (SIR)
D. Attack Rate
Correct Answer: C. Standardized Infection Ratio (SIR)
Detailed Rationale: The SIR is a summary measure used to track HAIs
over time, calculated by dividing the number of observed infections by
the number of predicted infections based on risk-adjusted models.
Question 7
When evaluating a diagnostic screening test for an emerging infection,
what does a high sensitivity indicate?
A. The test has a high proportion of false-negative results
B. The test correctly identifies a high percentage of individuals who
actually have the disease
Control Practice Questions & Detailed Rationales (2026/2027)
Question 1
An infection preventionist is investigating an outbreak of surgical site
infections (SSIs) following cardiac surgeries. Which study design is most
appropriate for a rapid initial evaluation to identify specific risk factors
and exposures among cases versus non-cases?
A. Randomized controlled trial
B. Retrospective case-control study
C. Cross-sectional prevalence survey
D. Prospective cohort study
Correct Answer: B. Retrospective case-control study
Detailed Rationale: A retrospective case-control study compares
patients who developed the infection (cases) with those who
underwent the same procedure without developing infection (controls)
to look backward at exposures and risk factors, making it highly efficient
for acute outbreak investigations.
Question 2
Which of the following measures represents an incidence density rate
used in healthcare-associated infection (HAI) surveillance?
A. Number of central line-associated bloodstream infections divided by
total patient discharges
,B. Number of catheter-associated urinary tract infections divided by
total patient-days × 1,000
C. Number of ventilator-associated events divided by total ventilator-
days × 1,000
D. Total number of surgical site infections divided by total number of
surgical procedures performed
Correct Answer: C. Number of ventilator-associated events divided by
total ventilator-days × 1,000
Detailed Rationale: Incidence density rates use person-time or device-
time (such as ventilator-days or central line-days) in the denominator,
accounting for the varying length of time patients are exposed to
specific risk devices.
Question 3
According to Spaulding’s classification, how must surgical instruments
that enter normally sterile tissue or the vascular system be processed
before reuse?
A. Low-level disinfection
B. Intermediate-level disinfection
C. High-level disinfection
D. Sterilization
Correct Answer: D. Sterilization
Detailed Rationale: Critical items (such as surgical instruments, cardiac
catheters, and implants) enter sterile body tissues or vascular systems
,and must be sterile, as any microbial contamination can result in direct
transmission and severe infection.
Question 4
Which type of airflow is required for an Airborne Infection Isolation
Room (AIIR) housing a patient with suspected pulmonary tuberculosis?
A. Positive pressure with at least 12 air exchanges per hour
B. Negative pressure with at least 6 to 12 air exchanges per hour and air
exhausted directly outdoors or through a HEPA filter
C. Neutral pressure with natural window ventilation
D. Laminar airflow with downward vertical filtration
Correct Answer: B. Negative pressure with at least 6 to 12 air exchanges
per hour and air exhausted directly outdoors or through a HEPA filter
Detailed Rationale: Negative pressure airflow ensures that air flows
into the isolation room when the door is opened rather than leaking out
into clinical corridors, preventing the escape of infectious droplet nuclei.
Question 5
What is the primary mode of transmission for Bordetella pertussis in a
healthcare facility?
A. Airborne droplet nuclei persisting for hours across long distances
B. Large respiratory droplets generated during coughing, sneezing, or
talking
C. Direct percutaneous inoculation via contaminated sharps
D. Fecal-oral contamination from environmental surfaces
, Correct Answer: B. Large respiratory droplets generated during
coughing, sneezing, or talking
Detailed Rationale: Bordetella pertussis is transmitted primarily via
large respiratory droplets that travel short distances (typically 3 feet or
less) and land on mucosal surfaces, requiring Droplet Precautions.
Question 6
Which statistical metric is utilized by the National Healthcare Safety
Network (NHSN) to compare the actual number of reported infections
in a facility to the predicted number based on risk-adjusted national
baseline data?
A. Odds Ratio (OR)
B. Relative Risk (RR)
C. Standardized Infection Ratio (SIR)
D. Attack Rate
Correct Answer: C. Standardized Infection Ratio (SIR)
Detailed Rationale: The SIR is a summary measure used to track HAIs
over time, calculated by dividing the number of observed infections by
the number of predicted infections based on risk-adjusted models.
Question 7
When evaluating a diagnostic screening test for an emerging infection,
what does a high sensitivity indicate?
A. The test has a high proportion of false-negative results
B. The test correctly identifies a high percentage of individuals who
actually have the disease
