Topic 2: Study Design

Question 1

What does IMRAD stand for in the context of a journal article?

Answer 1

• Introduction
• Methods
• Results
• Discussion

IMRAD is a standard structure that helps readers quickly locate and evaluate key information in research papers.

Question 2

What is the purpose of the Title section in a journal article?

Answer 2

Clearly identifies the topic and scope of the study

Key information includes the main research question, study population, and study design.

Question 3

What key information is included in the Abstract section of a journal article?

Answer 3

• Background and aim
• Methods
• Key results
• Main conclusion or implication

The abstract provides a concise summary of the entire article and often determines whether the full article is read.

Question 4

What is the purpose of the Introduction section in a journal article?

Answer 4

Explains why the study was conducted

It includes background, literature review, knowledge gaps, and the research aim or hypothesis.

Question 5

What does the Methods section describe in a journal article?

Answer 5

How the study was conducted

Key information includes study design, participant selection, interventions, outcome measures, and ethical approval.

Question 6

What type of information is presented in the Results section of a journal article?

Answer 6

• Participant characteristics
• Primary and secondary outcomes
• Statistical results
• Tables and figures

This section presents findings without interpretation, providing objective evidence.

Question 7

What is the purpose of the Discussion section in a journal article?

Answer 7

Interprets the findings and places them in context

It summarizes main findings, compares with previous studies, and discusses implications.

Question 8

What does the Conclusion section provide in a journal article?

Answer 8

A concise take-home message

It includes overall interpretation of findings and implications for practice, policy, or research.

Question 9

What is the purpose of the References section in a journal article?

Answer 9

Acknowledges sources and supports credibility

It includes all cited literature formatted according to journal style.

Question 10

Name some additional sections that are often included in a journal article.

Answer 10

• Acknowledgements
• Conflict of Interest Statement
• Funding Statement
• Ethical Approval
• Supplementary Material

These sections provide further context and transparency regarding the study.

Question 11

What are the different research study designs used depending on the research question?

Answer 11

• Experimental studies
• Observational studies
• Descriptive studies
• Analytical and synthesis studies
• Qualitative research

Each type has distinct advantages and limitations.

Question 12

What is the gold standard for determining causality in research?

Answer 12

Randomised Controlled Trials (RCTs)

RCTs involve random assignment to intervention or control groups.

Question 13

List the advantages of Randomised Controlled Trials (RCTs).

Answer 13

• Gold standard for determining causality
• Randomisation reduces confounding and bias
• High internal validity

RCTs are best for testing the effectiveness of interventions.

Question 14

List the disadvantages of Randomised Controlled Trials (RCTs).

Answer 14

• Expensive and time-consuming
• Ethical constraints (e.g. placebo use)
• May lack generalisability due to strict inclusion criteria

These factors can limit the feasibility of RCTs.

Question 15

What are Non-randomised (Quasi-experimental) studies?

Answer 15

Intervention is applied without random assignment

Useful in real-world or policy settings.

Question 16

What are the advantages of Cohort studies?

Answer 16

• Can assess incidence and temporal relationships
• Useful for studying rare exposures
• Can examine multiple outcomes

Cohort studies follow groups defined by exposure over time.

Question 17

What are the disadvantages of Cohort studies?

Answer 17

• Time-consuming and costly
• Loss to follow-up
• Confounding remains a risk

These factors can affect the validity of cohort studies.

Question 18

What are the advantages of Case–control studies?

Answer 18

• Efficient for rare diseases
• Faster and cheaper than cohort studies
• Requires smaller sample sizes

Case-control studies compare people with a condition to those without.

Question 19

What are the disadvantages of Case–control studies?

Answer 19

• Recall and selection bias
• Cannot directly calculate incidence
• Temporal relationships less clear

These limitations can affect the reliability of case-control studies.

Question 20

What are the advantages of Cross-sectional studies?

Answer 20

• Quick and inexpensive
• Useful for estimating prevalence
• Good for hypothesis generation

Cross-sectional studies measure exposure and outcome at a single point in time.

Question 21

What are the disadvantages of Cross-sectional studies?

Answer 21

• Cannot establish causality
• No temporal relationship
• Susceptible to confounding

These factors limit the conclusions that can be drawn from cross-sectional studies.

Question 22

What are the advantages of Case reports and case series?

Answer 22

• Identify new or rare conditions
• Generate hypotheses
• Simple and low cost

These studies provide detailed descriptions of one or several patients.

Question 23

What are the disadvantages of Case reports and case series?

Answer 23

• No control group
• Cannot infer causation
• High risk of bias

These limitations affect the strength of conclusions drawn from case reports.

Question 24

What are the advantages of Ecological studies?

Answer 24

• Useful for public health trends
• Fast and inexpensive
• Uses existing data

Ecological studies use population-level data rather than individual data.

Question 25

What are the **disadvantages** of **Ecological studies**?

Answer 25

* Ecological fallacy (group data ≠ individual risk) * Limited control over confounders ## Footnote These factors can lead to misleading conclusions in ecological studies.

Question 26

What are the **advantages** of **Systematic reviews**?

Answer 26

* High level of evidence * Transparent and reproducible * Reduces bias ## Footnote Systematic reviews summarize all relevant studies on a topic.

Question 27

What are the **disadvantages** of **Systematic reviews**?

Answer 27

* Quality depends on included studies * Time-intensive to conduct ## Footnote These factors can affect the overall reliability of systematic reviews.

Question 28

What are the **advantages** of **Meta-analyses**?

Answer 28

* Increased statistical power * More precise effect estimates ## Footnote Meta-analyses statistically combine results from multiple studies.

Question 29

What are the **disadvantages** of **Meta-analyses**?

Answer 29

* Publication bias * Heterogeneity between studies ## Footnote These issues can complicate the interpretation of meta-analyses.

Question 30

What are the **advantages** of **Qualitative research**?

Answer 30

* Provides depth and context * Captures patient perspectives * Useful for complex or sensitive topics ## Footnote Qualitative research explores experiences, perceptions, and behaviours.

Question 31

What are the **disadvantages** of **Qualitative research**?

Answer 31

* Not generalisable * Subjective interpretation * Cannot quantify effect sizes ## Footnote These limitations can affect the applicability of qualitative research findings.

Question 32

What is the **main strength** of **RCTs**?

Answer 32

Causality ## Footnote RCTs are considered the gold standard for establishing causal relationships.

Question 33

What is the **main limitation** of **RCTs**?

Answer 33

Cost, ethics ## Footnote These factors can limit the feasibility of conducting RCTs.

Question 34

What is the **main strength** of **Cohort studies**?

Answer 34

Temporal relationship ## Footnote Cohort studies can establish the timing of exposure and outcome.

Question 35

What is the **main limitation** of **Cohort studies**?

Answer 35

Time, confounding ## Footnote These factors can complicate the results of cohort studies.

Question 36

What is the **main strength** of **Case–control studies**?

Answer 36

Rare diseases ## Footnote Case-control studies are efficient for studying conditions that are not common.

Question 37

What is the **main limitation** of **Case–control studies**?

Answer 37

Bias ## Footnote Bias can significantly affect the validity of case-control studies.

Question 38

What is the **main strength** of **Cross-sectional studies**?

Answer 38

Prevalence ## Footnote Cross-sectional studies are useful for estimating how common a condition is at a specific time.

Question 39

What is the **main limitation** of **Cross-sectional studies**?

Answer 39

No causality ## Footnote Cross-sectional studies cannot establish cause-and-effect relationships.

Question 40

What is the **main strength** of **Case reports**?

Answer 40

Novel findings ## Footnote Case reports can highlight new or rare conditions.

Question 41

What is the **main limitation** of **Case reports**?

Answer 41

No inference ## Footnote Case reports cannot be used to draw broader conclusions.

Question 42

What is the **main strength** of **Systematic reviews**?

Answer 42

High evidence ## Footnote Systematic reviews provide a comprehensive overview of existing research.

Question 43

What is the **main limitation** of **Systematic reviews**?

Answer 43

Dependent on study quality ## Footnote The quality of a systematic review is contingent on the quality of the studies included.

Question 44

What is the main distinction between **observational** and **experimental research designs**?

Answer 44

Observational: No intervention; Experimental: Active intervention ## Footnote Observational research observes exposures and outcomes, while experimental research tests causality through intervention.

Question 45

List the **key features** of **observational research**.

Answer 45

* No manipulation of variables * No randomisation * Includes cohort, case–control, and cross-sectional studies ## Footnote Observational research reflects real-world conditions and is more ethical for harmful exposures.

Question 46

What are the **advantages** of **observational research**?

Answer 46

* More ethical and feasible for harmful exposures * Reflects real-world conditions * Less expensive and time-consuming ## Footnote Observational studies are useful for studying associations without intervention.

Question 47

What are the **disadvantages** of **observational research**?

Answer 47

* Cannot firmly establish causality * More prone to bias and confounding ## Footnote These limitations affect the reliability of findings in observational studies.

Question 48

What is an example of **observational research**?

Answer 48

Studying the association between smoking and lung cancer using population data ## Footnote This example illustrates how observational research can identify potential health risks.

Question 49

List the **key features** of **experimental research**.

Answer 49

* Manipulation of variables * Often includes randomisation and control groups * Includes randomised controlled trials (RCTs) ## Footnote Experimental research is designed to test hypotheses through intervention.

Question 50

What are the **advantages** of **experimental research**?

Answer 50

* Strongest evidence for causality * Reduced confounding through randomisation * High internal validity ## Footnote These advantages make experimental research a powerful tool for establishing cause-and-effect relationships.

Question 51

What are the **disadvantages** of **experimental research**?

Answer 51

* Ethical constraints * Expensive and time-consuming * May have limited generalisability ## Footnote These factors can limit the applicability of experimental findings to broader populations.

Question 52

What is an example of **experimental research**?

Answer 52

Testing a new antihypertensive drug in an RCT ## Footnote This example demonstrates how experimental research can evaluate the effectiveness of treatments.

Question 53

What is the main focus of **qualitative research**?

Answer 53

Explores **experiences, meanings, and perspectives** ## Footnote Qualitative research aims to provide a rich understanding of complex topics.

Question 54

List the **key features** of **qualitative research**.

Answer 54

* Non-numerical data (words, narratives) * Methods include interviews, focus groups, observations * Inductive, exploratory approach ## Footnote These features allow qualitative research to capture in-depth insights.

Question 55

What are the **advantages** of **qualitative research**?

Answer 55

* Rich, in-depth understanding * Captures patient or participant perspectives * Useful for complex or sensitive topics ## Footnote These advantages make qualitative research valuable for exploring nuanced issues.

Question 56

What are the **disadvantages** of **qualitative research**?

Answer 56

* Small sample sizes * Subjective interpretation * Limited generalisability ## Footnote These limitations can affect the broader applicability of qualitative findings.

Question 57

What is an example of **qualitative research**?

Answer 57

Interviewing patients about their experience of chronic pain ## Footnote This example highlights how qualitative research can provide insights into personal experiences.

Question 58

What is the main focus of **quantitative research**?

Answer 58

Measures **variables numerically** and tests hypotheses ## Footnote Quantitative research aims to provide objective and reproducible findings.

Question 59

List the **key features** of **quantitative research**.

Answer 59

* Numerical data and statistical analysis * Structured instruments (surveys, lab measures) * Deductive approach ## Footnote These features enable quantitative research to test hypotheses rigorously.

Question 60

What are the **advantages** of **quantitative research**?

Answer 60

* Objective and reproducible * Allows statistical comparison and inference * Can be generalised to larger populations ## Footnote These advantages make quantitative research a powerful tool for hypothesis testing.

Question 61

What are the **disadvantages** of **quantitative research**?

Answer 61

* Limited depth or context * May oversimplify complex phenomena ## Footnote These limitations can restrict the understanding of nuanced issues in quantitative studies.

Question 62

What is an example of **quantitative research**?

Answer 62

Measuring pain scores before and after treatment ## Footnote This example illustrates how quantitative research can assess treatment effectiveness.

Question 63

What is the main distinction between **cross-sectional** and **longitudinal research**?

Answer 63

Cross-sectional: Data collected at one point in time; Longitudinal: Data collected repeatedly over time ## Footnote This distinction highlights the different approaches to data collection in research.

Question 64

List the **key features** of **cross-sectional research**.

Answer 64

* Snapshot of a population * Measures exposure and outcome simultaneously ## Footnote Cross-sectional research provides a quick overview of a population's characteristics.

Question 65

What are the **advantages** of **cross-sectional research**?

Answer 65

* Quick and inexpensive * Useful for estimating **prevalence** * Good for hypothesis generation ## Footnote These advantages make cross-sectional studies valuable for initial assessments.

Question 66

What are the **disadvantages** of **cross-sectional research**?

Answer 66

* Cannot determine temporal relationships * Cannot infer causality ## Footnote These limitations affect the ability to draw conclusions about cause-and-effect relationships.

Question 67

What is an example of **cross-sectional research**?

Answer 67

Surveying current rates of obesity in adults ## Footnote This example demonstrates how cross-sectional research can provide a snapshot of health trends.

Question 68

List the **key features** of **longitudinal research**.

Answer 68

* Tracks changes and developments * Includes cohort studies and follow-ups ## Footnote Longitudinal research allows for the observation of trends over time.

Question 69

What are the **advantages** of **longitudinal research**?

Answer 69

* Establishes temporal sequence * Can measure incidence and change * Stronger causal inference than cross-sectional ## Footnote These advantages make longitudinal studies powerful for understanding dynamics over time.

Question 70

What are the **disadvantages** of **longitudinal research**?

Answer 70

* Time-consuming and costly * Loss to follow-up ## Footnote These factors can limit the feasibility of conducting longitudinal studies.

Question 71

What is an example of **longitudinal research**?

Answer 71

Following a cohort over 10 years to assess cardiovascular risk ## Footnote This example illustrates how longitudinal research can track health outcomes over time.

Question 72

What is the **high-yield comparison** between observational and experimental research?

Answer 72

Observation vs intervention ## Footnote This comparison highlights the fundamental difference in approach between the two research designs.

Question 73

What is the **high-yield comparison** between qualitative and quantitative research?

Answer 73

Meaning vs measurement ## Footnote This comparison emphasizes the different focuses of qualitative and quantitative research.

Question 74

What is the **high-yield comparison** between cross-sectional and longitudinal research?

Answer 74

Snapshot vs follow-up ## Footnote This comparison illustrates the temporal focus of each research design.

Question 75

Summarize the **one-sentence exam summary** of research designs.

Answer 75

Research designs differ in whether researchers **intervene or observe**, **measure numbers or explore experiences**, and **collect data once or over time** ## Footnote Each approach offers distinct strengths and limitations depending on the research question.

Question 76

What is a **randomised clinical trial (RCT)**?

Answer 76

An experimental study design used to evaluate the effectiveness of an intervention by comparing outcomes between groups ## Footnote Core features include randomisation, control groups, intervention, blinding, prospective design, predefined outcomes, and ethical oversight.

Question 77

What does **randomisation** in RCTs aim to reduce?

Answer 77

Selection bias and confounding ## Footnote Participants are randomly allocated to intervention and control groups.

Question 78

What is the purpose of a **control group** in RCTs?

Answer 78

Comparison against placebo, standard treatment, or no treatment ## Footnote This helps to assess the effect of the intervention.

Question 79

Define **blinding** in the context of RCTs.

Answer 79

* Single-blind: participant unaware * Double-blind: participant and researcher unaware ## Footnote Reduces performance and assessment bias.

Question 80

What is a key characteristic of the **prospective design** in RCTs?

Answer 80

Outcomes are measured after the intervention is applied ## Footnote This design helps in establishing causal relationships.

Question 81

What are **predefined outcomes** in RCTs?

Answer 81

Primary and secondary outcomes specified in advance ## Footnote This ensures clarity and focus in the study.

Question 82

What is required for ethical oversight in RCTs?

Answer 82

Informed consent and ethics committee approval ## Footnote This is crucial for protecting participants' rights.

Question 83

Why are RCTs considered the **strongest design** for establishing causal relationships?

Answer 83

High internal validity ## Footnote They minimize biases and confounding factors.

Question 84

List key **limitations** of RCTs.

Answer 84

* Expensive and time-consuming * Ethical constraints * Limited generalisability due to strict inclusion criteria ## Footnote These factors can affect the feasibility and applicability of RCTs.

Question 85

What is the difference between **primary research** and **secondary research**?

Answer 85

* Primary research: Collecting new, original data * Secondary research: Analysing existing research ## Footnote Primary research generates new evidence, while secondary research synthesises it.

Question 86

What are examples of **primary research**?

Answer 86

* Randomised controlled trials * Cohort studies * Case–control studies * Cross-sectional surveys * Qualitative interviews ## Footnote These studies collect new data to answer specific research questions.

Question 87

What are the **advantages** of primary research?

Answer 87

* High relevance to the research question * Greater control over study design and data quality ## Footnote This allows for tailored approaches to specific hypotheses.

Question 88

What are the **disadvantages** of primary research?

Answer 88

* Time-consuming and costly * Ethical approval required * Often limited sample sizes ## Footnote These factors can hinder the execution of primary research.

Question 89

What does **secondary research** involve?

Answer 89

Analysing, summarising, or synthesising existing research ## Footnote It does not involve participant recruitment.

Question 90

List examples of **secondary research**.

Answer 90

* Systematic reviews * Meta-analyses * Narrative reviews * Clinical guidelines ## Footnote These types of research utilize previously published data.

Question 91

What are the **advantages** of secondary research?

Answer 91

* Efficient and cost-effective * Can provide high-level evidence * Useful for clinical decision-making ## Footnote Secondary research can quickly synthesize existing knowledge.

Question 92

What are the **disadvantages** of secondary research?

Answer 92

* Dependent on quality of existing studies * Cannot correct flaws in original research ## Footnote The validity of secondary research is tied to the studies it reviews.

Question 93

What is a **systematic review**?

Answer 93

A structured, transparent method of identifying, appraising, and synthesising all relevant studies on a specific question ## Footnote It includes clearly defined research questions and a comprehensive literature search.

Question 94

List the **general features** of a systematic review.

Answer 94

* Clearly defined research question * Pre-specified protocol * Comprehensive literature search * Explicit inclusion and exclusion criteria * Critical appraisal of study quality * Structured synthesis of findings ## Footnote These features ensure thoroughness and reliability.

Question 95

What are the **strengths** of systematic reviews?

Answer 95

* Reduces bias compared to narrative reviews * Provides a comprehensive overview of evidence * High level of evidence ## Footnote They are considered rigorous and reliable sources of information.

Question 96

What are the **limitations** of systematic reviews?

Answer 96

* Quality depends on included studies * Time- and labour-intensive * Can be affected by publication bias ## Footnote These factors can impact the overall findings of the review.

Question 97

What is a **meta-analysis**?

Answer 97

A statistical technique that may be included within a systematic review to quantitatively combine results from multiple studies ## Footnote It increases statistical power and precision.

Question 98

List the **general features** of a meta-analysis.

Answer 98

* Combines effect sizes from individual studies * Often presented using forest plots * Increases statistical power and precision ## Footnote These features enhance the analysis of data.

Question 99

What are the **strengths** of meta-analysis?

Answer 99

* More precise effect estimates * Can detect effects not seen in individual studies ## Footnote This makes meta-analyses valuable for drawing conclusions.

Question 100

What are the **limitations** of meta-analysis?

Answer 100

* Heterogeneity between studies can limit validity * Poor studies weaken results * Susceptible to publication bias ## Footnote These limitations can affect the reliability of the findings.

Question 101

True or false: A **systematic review** may include a **meta-analysis**.

Answer 101

TRUE ## Footnote A meta-analysis cannot exist without a systematic review framework.

Question 102

True or false: A **meta-analysis** can exist independently of a **systematic review**.

Answer 102

FALSE ## Footnote A meta-analysis is always part of a systematic review.

Question 103

What is the purpose of **epidemiological study designs**?

Answer 103

To investigate the **distribution and determinants of health and disease** in populations ## Footnote These designs help in understanding how diseases affect different groups.

Question 104

What is a **cohort study**?

Answer 104

A study that follows a group of people **over time**, comparing outcomes between those **exposed** and **not exposed** to a risk factor ## Footnote Cohort studies can be **prospective** or **retrospective**.

Question 105

List the **key features** of a cohort study.

Answer 105

* Participants grouped by **exposure status** * Outcomes measured **prospectively** (or retrospectively using records) ## Footnote This design allows for clear temporal relationships.

Question 106

What outcomes do cohort studies measure?

Answer 106

* **Incidence** * Relative risk (RR) * Risk difference ## Footnote These measures help assess the impact of exposures on health outcomes.

Question 107

What are the **advantages** of cohort studies?

Answer 107

* Clear temporal relationship (exposure → outcome) * Can study multiple outcomes * Good for rare exposures ## Footnote These advantages make cohort studies valuable for understanding long-term effects.

Question 108

What are the **disadvantages** of cohort studies?

Answer 108

* Time-consuming and expensive * Loss to follow-up * Inefficient for rare diseases ## Footnote These factors can limit the feasibility of cohort studies.

Question 109

What is a **case–control study**?

Answer 109

A study that starts with people **who already have a disease (cases)** and compares them to those **without the disease (controls)** ## Footnote This design assesses past exposures to identify risk factors.

Question 110

List the **key features** of a case–control study.

Answer 110

* Participants grouped by **outcome status** * Looks backward to assess exposure * Usually retrospective ## Footnote This design is efficient for studying rare diseases.

Question 111

What do case–control studies measure?

Answer 111

* **Odds ratio (OR)** ## Footnote The odds ratio is used as an estimate of relative risk.

Question 112

What are the **advantages** of case–control studies?

Answer 112

* Efficient for **rare diseases** * Faster and cheaper than cohort studies * Requires smaller sample sizes ## Footnote These advantages make case–control studies practical for certain research questions.

Question 113

What are the **disadvantages** of case–control studies?

Answer 113

* Recall bias * Selection bias * Cannot calculate incidence directly ## Footnote These limitations can affect the validity of findings.

Question 114

True or false: **Cohort studies** begin with exposure and measure incidence.

Answer 114

TRUE ## Footnote This distinguishes cohort studies from case–control studies.

Question 115

What does **prevalence** refer to?

Answer 115

The **proportion of a population that has a disease at a specific point or period in time** ## Footnote Prevalence helps in understanding the burden of disease in a population.

Question 116

List the **types of prevalence**.

Answer 116

* **Point prevalence**: disease at a single time point * **Period prevalence**: disease over a specified time period ## Footnote These types help in measuring disease burden over different time frames.

Question 117

What is the **formula** for prevalence?

Answer 117

> Existing cases ÷ total population ## Footnote This formula provides a basic calculation for determining prevalence.

Question 118

What is **incidence**?

Answer 118

The **number of new cases** of a disease occurring in a population **over a defined time period** ## Footnote Incidence is crucial for understanding disease dynamics.

Question 119

List the **types of incidence**.

Answer 119

* **Incidence rate** (person-time) * **Cumulative incidence** (risk) ## Footnote These types help in assessing the risk of developing a disease.

Question 120

What is the **formula** for incidence?

Answer 120

> New cases ÷ population at risk ## Footnote This formula helps in calculating the incidence of a disease.

Question 121

What are **mortality measures**?

Answer 121

Measures **death** in a population ## Footnote These measures are essential for monitoring population health.

Question 122

List common **mortality measures**.

Answer 122

* **Crude mortality rate** * **Cause-specific mortality rate** * **Age-specific mortality rate** * **Infant mortality rate** * **Maternal mortality ratio** ## Footnote These measures help in evaluating public health interventions.

Question 123

What are **morbidity measures**?

Answer 123

Measures **illness, disease, or disability** ## Footnote These measures assess the burden of disease in a population.

Question 124

List common **morbidity measures**.

Answer 124

* Incidence * Prevalence * Hospitalisation rates * Disability rates ## Footnote These measures are used for planning healthcare services.

Question 125

What do **reproductive and fertility measures** assess?

Answer 125

Measure **population growth and reproductive health** ## Footnote These measures are important for understanding demographic trends.

Question 126

List examples of **reproductive and fertility measures**.

Answer 126

* **Fertility rate**: births per woman * **Crude birth rate** * **Perinatal mortality rate** * **Neonatal mortality rate** ## Footnote These measures help in maternal and child health monitoring.

Question 127

What is **life expectancy**?

Answer 127

Average number of years a person is expected to live ## Footnote It serves as a summary indicator of population health.

Question 128

What are **Quality-adjusted life years (QALYs)**?

Answer 128

Combines **quantity and quality of life** ## Footnote QALYs are used in health economics to evaluate health interventions.

Question 129

What are **Disability-adjusted life years (DALYs)**?

Answer 129

Measures years of healthy life lost due to illness or death ## Footnote DALYs are used for global disease burden comparisons.

Question 130

What does the **high-yield summary table** reflect?

Answer 130

| Measure | What it reflects | | ----------- | -------------------------- | | Incidence | Risk of developing disease | | Prevalence | Burden of disease | | Mortality | Death rates | | Morbidity | Illness and disability | | Fertility | Population reproduction | | QALYs/DALYs | Overall health impact | ## Footnote This table summarizes key health measures.

Question 131

What is a **population pyramid**?

Answer 131

A graphical representation of a population’s age and sex structure at a specific point in time ## Footnote X-axis: population size (males on the left, females on the right); Y-axis: age groups (usually 5-year bands)

Question 132

What are the characteristics of an **expansive** population pyramid?

Answer 132

* Broad base, narrow top * High birth rates, high (or improving) mortality * Young population ## Footnote Seen in many low- and middle-income countries.

Question 133

What does a **stationary** population pyramid look like?

Answer 133

* Rectangular shape * Low birth and death rates * Stable population growth ## Footnote Seen in many high-income countries.

Question 134

Describe the characteristics of a **constrictive** population pyramid.

Answer 134

* Narrow base, wider middle/upper sections * Low fertility, ageing population ## Footnote Seen in countries with declining birth rates.

Question 135

How do population pyramids help epidemiologists to **predict disease patterns**?

Answer 135

* Young populations → infectious disease, maternal/child health issues * Older populations → chronic disease, cancer, dementia ## Footnote They assist in understanding the health needs of different age groups.

Question 136

What are the uses of population pyramids in **planning health services**?

Answer 136

* Paediatric vs geriatric care needs * Workforce and hospital planning ## Footnote They help allocate resources effectively based on demographic needs.

Question 137

What demographic risks can be identified using **population pyramids**?

Answer 137

* Gender-specific health issues * Dependency ratios ## Footnote They provide insights into potential health challenges within a population.

Question 138

What is **public health surveillance**?

Answer 138

The ongoing, systematic collection, analysis, interpretation, and dissemination of health data to guide public health action ## Footnote It is essential for monitoring population health and detecting outbreaks.

Question 139

What is the focus of **disease surveillance**?

Answer 139

Health outcomes ## Footnote Examples include infectious disease notifications, cancer registries, and mortality databases.

Question 140

What is the purpose of **risk factor surveillance**?

Answer 140

* Identify emerging health risks * Guide prevention strategies * Monitor effectiveness of public health interventions ## Footnote It focuses on determinants of disease.

Question 141

What are the types of **surveillance systems**?

Answer 141

* Passive (routine reporting) * Active (proactive case finding) * Sentinel (selected sites) * Syndromic (symptom-based early detection) ## Footnote Each type serves different public health monitoring needs.

Question 142

What is **primordial prevention**?

Answer 142

Prevent development of risk factors through policy and environmental changes ## Footnote Example: tobacco taxation, urban design promoting activity.

Question 143

What does **primary prevention** aim to achieve?

Answer 143

Reduce exposure to risk factors and prevent disease onset ## Footnote Example: vaccination, smoking cessation programs.

Question 144

What is the goal of **secondary prevention**?

Answer 144

Early detection and treatment ## Footnote Example: cancer screening, blood pressure checks.

Question 145

What does **tertiary prevention** focus on?

Answer 145

Reduce complications and disability ## Footnote Example: rehabilitation, chronic disease management.

Question 146

Why is **surveillance** essential in epidemiology?

Answer 146

* Evidence-based public health decision-making * Timely outbreak response * Efficient resource allocation * Evaluation of prevention and control programs ## Footnote It provides critical data for public health actions.

Question 147

What do population pyramids describe and how are they used in epidemiology?

Answer 147

They describe the age–sex structure of a population and are used to predict disease burden, plan health services, and understand demographic transitions ## Footnote They are essential tools for public health planning.

Question 148

What is the main focus of **surveillance** in public health?

Answer 148

Continuous collection and analysis of health data to monitor population health, detect outbreaks, and guide public health interventions ## Footnote It operates at primordial, primary, secondary, and tertiary levels.