NATIONAL BOARD OF PUBLIC HEALTH EXAMINERS (NBPHE) – CPH CERTIFIED IN PUBLIC
HEALTH – QUESTIONS AND ANSWERS | 2026/2027 LATEST UPDATE
SECTION 1: DATA, ANALYTICS, AND INFORMATICS
Questions 1–12
1. Which distinction most accurately separates primary from secondary public health
data?
A) Primary data are collected directly for the current research purpose, whereas secondary
data were previously collected for another purpose.
B) Primary data are always qualitative, whereas secondary data are always quantitative.
C) Primary data are obtained only from surveillance systems, whereas secondary data come
only from surveys.
D) Primary data cannot be collected from populations, whereas secondary data can.
Correct Answer: Primary data are collected directly for the current research purpose,
whereas secondary data were previously collected for another purpose.
Rationale: Primary data are generated specifically to answer a current research or program
question. Secondary data already exist and are repurposed for the current analysis, often
saving time and resources. Examples include a newly administered survey versus an existing
census database. The distinction concerns the purpose and timing of collection, not whether
data are qualitative or quantitative.
2. A health department wants historical mortality information for several counties without
conducting a new survey. Which source would most appropriately provide secondary
data?
A) Newly administered household interviews
B) Vital statistics records
C) Newly collected focus-group transcripts
D) Direct participant observations
Correct Answer: Vital statistics records
Rationale: Vital statistics systems contain routinely collected information about events such
as births and deaths. They are therefore an established secondary data source when
researchers analyze information for a new public health purpose. Household interviews,
focus groups, and observations would require new primary data collection. Using existing
records can provide broad historical coverage efficiently.
,3. Before administering a community survey, which action most directly improves the
validity of the measurement instrument?
A) Increasing the number of answer choices for every question
B) Removing all demographic questions
C) Selecting or adapting a validated instrument appropriate for the construct being
measured
D) Allowing respondents to modify the wording of each item
Correct Answer: Selecting or adapting a validated instrument appropriate for the construct
being measured
Rationale: A validated instrument has undergone evaluation demonstrating that it measures
its intended construct appropriately. Selecting a tool that matches the population and
research question strengthens measurement validity. Adding unnecessary response choices
or allowing uncontrolled wording changes can reduce consistency. Demographic questions
may also be important when they support appropriate analysis.
4. A public health analyst discovers duplicate records, inconsistent date formats, and
impossible ages in a surveillance database. What should occur before statistical analysis?
A) Publish the dataset to obtain external feedback
B) Delete all records containing missing values
C) Increase the sample size
D) Clean and standardize the data while documenting corrections
Correct Answer: Clean and standardize the data while documenting corrections
Rationale: Data cleaning identifies errors, inconsistencies, duplicates, and implausible values
before analysis. Standardization improves consistency across records and helps prevent
misleading results. Corrections should be documented so the process remains transparent
and reproducible. Automatically deleting every incomplete record can introduce bias and is
not an appropriate universal solution.
5. A county reports 2,000 existing diabetes cases among 100,000 residents on July 1.
Which measure does this calculation primarily represent?
A) Incidence
B) Prevalence
C) Case-fatality ratio
D) Relative risk
Correct Answer: Prevalence
,Rationale: Prevalence describes the proportion of a population that has a condition at a
specified point or during a specified period. The example counts existing diabetes cases in the
population on a particular date. Incidence instead measures new cases occurring over a
period. Relative risk compares disease occurrence between exposure groups rather than
describing the overall burden.
6. An analyst wants to show monthly trends in influenza activity over a two-year period.
Which visualization is most appropriate?
A) Line graph
B) Pie chart
C) Box-only organizational diagram
D) Geographic boundary map
Correct Answer: Line graph
Rationale: A line graph is particularly useful for displaying changes in a measure across
ordered time points. Connecting observations allows the viewer to identify trends, peaks,
declines, and seasonal patterns. Pie charts are better suited to showing parts of a whole,
while maps emphasize geographic distribution. The visualization should match the analytical
question.
7. Which statement best characterizes a limitation of surveillance data?
A) Surveillance data can never be used for population-level monitoring.
B) Surveillance systems always include every case occurring in a population.
C) Reporting completeness and case definitions can affect the accuracy and comparability of
surveillance estimates.
D) Surveillance data cannot identify temporal patterns.
Correct Answer: Reporting completeness and case definitions can affect the accuracy and
comparability of surveillance estimates.
Rationale: Surveillance systems depend on consistent case definitions and reporting
processes. Underreporting, changes in reporting practices, or revised definitions can
influence observed trends. Surveillance remains valuable for monitoring population health,
but users must understand its limitations. Interpreting apparent changes requires
consideration of both disease occurrence and characteristics of the surveillance system.
8. Which measure describes the occurrence of new cases of a disease in a population
during a specified period?
A) Prevalence
B) Mortality
, C) Incidence
D) Proportionate mortality
Correct Answer: Incidence
Rationale: Incidence measures new cases arising within a population at risk during a defined
period. It is useful for studying disease occurrence and identifying factors associated with
developing a condition. Prevalence includes existing cases and therefore reflects disease
burden. Mortality concerns deaths rather than new disease events.
9. A report contains a median household income of $48,000 and an interquartile range of
$12,000. What does the interquartile range describe?
A) The difference between the maximum and minimum values
B) The range containing the middle 50% of observations
C) The arithmetic average of all observations
D) The percentage of observations below the mean
Correct Answer: The range containing the middle 50% of observations
Rationale: The interquartile range is calculated from the third quartile minus the first quartile
and represents the central 50% of observations. It is relatively resistant to extreme values
compared with the full range. The mean describes an arithmetic average, while the
maximum-minus-minimum calculation describes the total range.
10. Why is informatics important to contemporary public health practice?
A) It eliminates the need for professional judgment.
B) It allows all public health decisions to be automated.
C) It replaces epidemiologic investigation.
D) It supports the organized collection, integration, analysis, and use of health information.
Correct Answer: It supports the organized collection, integration, analysis, and use of
health information.
Rationale: Public health informatics supports the effective management and use of
information for surveillance, program operations, analysis, and decision-making. It can
improve interoperability, timeliness, and accessibility of information. Informatics does not
eliminate professional judgment or replace epidemiologic reasoning. Instead, it provides
infrastructure and tools that strengthen those activities.
11. A qualitative study reports recurring themes from interviews with community
members. Which interpretation is most appropriate?
A) The themes can provide contextual insight into experiences and perceptions.
HEALTH – QUESTIONS AND ANSWERS | 2026/2027 LATEST UPDATE
SECTION 1: DATA, ANALYTICS, AND INFORMATICS
Questions 1–12
1. Which distinction most accurately separates primary from secondary public health
data?
A) Primary data are collected directly for the current research purpose, whereas secondary
data were previously collected for another purpose.
B) Primary data are always qualitative, whereas secondary data are always quantitative.
C) Primary data are obtained only from surveillance systems, whereas secondary data come
only from surveys.
D) Primary data cannot be collected from populations, whereas secondary data can.
Correct Answer: Primary data are collected directly for the current research purpose,
whereas secondary data were previously collected for another purpose.
Rationale: Primary data are generated specifically to answer a current research or program
question. Secondary data already exist and are repurposed for the current analysis, often
saving time and resources. Examples include a newly administered survey versus an existing
census database. The distinction concerns the purpose and timing of collection, not whether
data are qualitative or quantitative.
2. A health department wants historical mortality information for several counties without
conducting a new survey. Which source would most appropriately provide secondary
data?
A) Newly administered household interviews
B) Vital statistics records
C) Newly collected focus-group transcripts
D) Direct participant observations
Correct Answer: Vital statistics records
Rationale: Vital statistics systems contain routinely collected information about events such
as births and deaths. They are therefore an established secondary data source when
researchers analyze information for a new public health purpose. Household interviews,
focus groups, and observations would require new primary data collection. Using existing
records can provide broad historical coverage efficiently.
,3. Before administering a community survey, which action most directly improves the
validity of the measurement instrument?
A) Increasing the number of answer choices for every question
B) Removing all demographic questions
C) Selecting or adapting a validated instrument appropriate for the construct being
measured
D) Allowing respondents to modify the wording of each item
Correct Answer: Selecting or adapting a validated instrument appropriate for the construct
being measured
Rationale: A validated instrument has undergone evaluation demonstrating that it measures
its intended construct appropriately. Selecting a tool that matches the population and
research question strengthens measurement validity. Adding unnecessary response choices
or allowing uncontrolled wording changes can reduce consistency. Demographic questions
may also be important when they support appropriate analysis.
4. A public health analyst discovers duplicate records, inconsistent date formats, and
impossible ages in a surveillance database. What should occur before statistical analysis?
A) Publish the dataset to obtain external feedback
B) Delete all records containing missing values
C) Increase the sample size
D) Clean and standardize the data while documenting corrections
Correct Answer: Clean and standardize the data while documenting corrections
Rationale: Data cleaning identifies errors, inconsistencies, duplicates, and implausible values
before analysis. Standardization improves consistency across records and helps prevent
misleading results. Corrections should be documented so the process remains transparent
and reproducible. Automatically deleting every incomplete record can introduce bias and is
not an appropriate universal solution.
5. A county reports 2,000 existing diabetes cases among 100,000 residents on July 1.
Which measure does this calculation primarily represent?
A) Incidence
B) Prevalence
C) Case-fatality ratio
D) Relative risk
Correct Answer: Prevalence
,Rationale: Prevalence describes the proportion of a population that has a condition at a
specified point or during a specified period. The example counts existing diabetes cases in the
population on a particular date. Incidence instead measures new cases occurring over a
period. Relative risk compares disease occurrence between exposure groups rather than
describing the overall burden.
6. An analyst wants to show monthly trends in influenza activity over a two-year period.
Which visualization is most appropriate?
A) Line graph
B) Pie chart
C) Box-only organizational diagram
D) Geographic boundary map
Correct Answer: Line graph
Rationale: A line graph is particularly useful for displaying changes in a measure across
ordered time points. Connecting observations allows the viewer to identify trends, peaks,
declines, and seasonal patterns. Pie charts are better suited to showing parts of a whole,
while maps emphasize geographic distribution. The visualization should match the analytical
question.
7. Which statement best characterizes a limitation of surveillance data?
A) Surveillance data can never be used for population-level monitoring.
B) Surveillance systems always include every case occurring in a population.
C) Reporting completeness and case definitions can affect the accuracy and comparability of
surveillance estimates.
D) Surveillance data cannot identify temporal patterns.
Correct Answer: Reporting completeness and case definitions can affect the accuracy and
comparability of surveillance estimates.
Rationale: Surveillance systems depend on consistent case definitions and reporting
processes. Underreporting, changes in reporting practices, or revised definitions can
influence observed trends. Surveillance remains valuable for monitoring population health,
but users must understand its limitations. Interpreting apparent changes requires
consideration of both disease occurrence and characteristics of the surveillance system.
8. Which measure describes the occurrence of new cases of a disease in a population
during a specified period?
A) Prevalence
B) Mortality
, C) Incidence
D) Proportionate mortality
Correct Answer: Incidence
Rationale: Incidence measures new cases arising within a population at risk during a defined
period. It is useful for studying disease occurrence and identifying factors associated with
developing a condition. Prevalence includes existing cases and therefore reflects disease
burden. Mortality concerns deaths rather than new disease events.
9. A report contains a median household income of $48,000 and an interquartile range of
$12,000. What does the interquartile range describe?
A) The difference between the maximum and minimum values
B) The range containing the middle 50% of observations
C) The arithmetic average of all observations
D) The percentage of observations below the mean
Correct Answer: The range containing the middle 50% of observations
Rationale: The interquartile range is calculated from the third quartile minus the first quartile
and represents the central 50% of observations. It is relatively resistant to extreme values
compared with the full range. The mean describes an arithmetic average, while the
maximum-minus-minimum calculation describes the total range.
10. Why is informatics important to contemporary public health practice?
A) It eliminates the need for professional judgment.
B) It allows all public health decisions to be automated.
C) It replaces epidemiologic investigation.
D) It supports the organized collection, integration, analysis, and use of health information.
Correct Answer: It supports the organized collection, integration, analysis, and use of
health information.
Rationale: Public health informatics supports the effective management and use of
information for surveillance, program operations, analysis, and decision-making. It can
improve interoperability, timeliness, and accessibility of information. Informatics does not
eliminate professional judgment or replace epidemiologic reasoning. Instead, it provides
infrastructure and tools that strengthen those activities.
11. A qualitative study reports recurring themes from interviews with community
members. Which interpretation is most appropriate?
A) The themes can provide contextual insight into experiences and perceptions.
