Improving Health (IH)

Question 1

What is meant by the term ‘incidence’?

Answer 1

The number of new health-related events that occur in a defined population within a specified period of time

Question 2

How may incidence be represented numerically? (3)

Answer 2

• Frequency count; the number of new cases
• Proportion; a percentage/decimal of the population
• Rate; a number of cases per number of person-years

Question 3

What is meant by the term ‘prevalence’?

Answer 3

The number of individuals who have a disease as a proportion of the at risk population

Question 4

Outline the two main ways of expressing prevalence? (2)

Answer 4

• Point prevalence; the proportion of individuals with a disease at a specific timepoint
• Period prevalence; the proportion of individuals with a disease over a certain period of time

Question 5

Outline the two main ways by which prevalence may be high? (2)

Answer 5

• High incidence
• Long duration of the disease

Question 6

The larger the relative risk (RR) the […]

Answer 6

The larger the relative risk (RR) the more likely the exposed group is to develop the outcome compared to the non-exposed group

Question 7

The absolute risk reduction (ARR) implies that for every 100 members of the exposed group, […], compared to the number of cases of the disease in the non-exposed group

Answer 7

The absolute risk reduction (ARR) implies that for every 100 members of the exposed group, there will be a number of people equal to the value of the ARR more cases of the disease, compared to the number of cases of the disease in the non-exposed group

Question 8

Outline the hierarchy of evidence? (8)

Answer 8

• Systematic review or meta-analysis of ≥ 2 randomised controlled trials (RCTs)
• Randomised controlled trial (RCT)
• Non-randomised experimental designs
• Cohort-studies
• Case-control studies
• Cross-sectional studies
• Case series/case studies
• Personal communication

Question 9

Outline the features of the Bradford-Hill criterion for causal relationships? (6)

Answer 9

• Strength of association; the stronger the association, the greater the likelihood that that association is the result of a causal relationship
• Dose-response; the greater the exposure to the risk the greater the incidence of the outcome
• Temporality; disease risk factor (exposure) must predate the disease (outcome)
• Consistency; same association demonstrated in multiple independent repeats
• Biological plausibility; biomedical reason or explanation to account for a causal relationship
• Reversibility; reduction or withdrawal of the risk factor should reduce/withdraw the outcome

Question 10

What is meant by the term ‘bias’?

Answer 10

A systematic error in the design, conduct or analysis of a study that results in a conclusion that is different from the truth

Question 11

Outline the main types of bias? (4)

Answer 11

• Selection bias; regarding the choice/inclusion of participants
• Information/measurement bias; regarding the appropriateness of exposure/outcome measures
• Observer bias; regarding the observers prior knowledge about the subject’s exposure to a risk factor and how this may influence results
• Recall bias; regarding the phenomenon where the subject with the outcome is more likely to remember an exposure than a subject without the outcome

Question 12

What is meant by the term ‘confounder’?

Answer 12

The presence of another factor that provides an explanation for the results other than the conclusion determined by the study

Question 13

What is meant by the term ‘chance’?

Answer 13

The likelihood that the observed effect/outcome could have been observed solely as a result of coincidence

Question 14

In relation to study design, what is the main factor that influences the likelihood of any conclusion reached being purely the result of chance?

Answer 14

Sample size; the larger the sample size, the less likely that the results are to have been determined purely by chance

Question 15

Which two variables are used to express chance? (2)

Answer 15

• Probability values (p-values)
• Confidence intervals (CIs)

Question 16

What can be inferred by a p-value of 0.001?

Answer 16

A p-value of 0.001 means that there is a 1 in (1 / 0.001 1000) 1000 (0.1%) chance that the observed difference is due to chance

Question 17

What is meant by the term ‘confidence interval (CI)’?

Answer 17

The confidence interval denotes the range of values that the true size of the effect lies within, for a given degree of assurance/confidence (%)

Question 18

What is meant by the term ‘standardisation’?

Answer 18

The technique for removing the effect of confounding variables (i.e. age) on individuals when comparing between different populations

Question 19

Outline the two main ways of standardising data in an epidemiological investigation? (2)

Answer 19

• Direct standardisation; observed rates in the population of interest are stratified according to the confounding variable and applied to a reference population
• Indirect standardisation; rates within a reference population are stratified according to to the confounding variable and applied to the population of interest

Question 20

In terms of the information that they require, what is the difference between direct and indirect standardisation? (2)

Answer 20

• Direct standardisation; used when the number of events within each of the confounding variable (i.e. age) groups of the population of interest is known
• Indirect standardisation; used when the number of events within each of the confounding variable (i.e. age) groups of the population of interest is not known

Question 21

Which parameter is calculated as a result of indirect standardisation when looking at mortality rates?

Answer 21

Standardised mortality ratio (SMR)

Question 22

What can the value of the standardised mortality rate (SMR) tell you about the mortality rate between two difference populations? (3)

Answer 22

• SMR < 1; the population of interest has a lower mortality rate than the reference population
• SMR 1; the population of interest has the same mortality rate as the reference population
• SMR > 1; the population of interest has a greater mortality rate than the reference population

Question 23

Outline the components of an audit cycle? (5)

Answer 23

• Set and agree the gold-standard for assessment/management of the problem
• Monitor performance against those standards over a certain timeframe (retrospective or prospective)
• Identify deviations from agreed standards and reasons why they occurred
• Implement changes to correct those unwanted deviations from the standard
• Repeat the cycle to assess the effectiveness of the implemented changes

Question 24

Outline the key features that make for good goal setting in the audit process? (5)

Answer 24

SMART;
- Specific
- Measurable
- Achievable
- Realistic
- Timely

Question 25

Outline the treatment-specific considerations that need to be taken into account by healthcare funding bodies when deciding whether or not to fund a new treatment? (4)

Answer 25

- **Safety**; whether the treatment can cause adverse effects - **Efficacy**; whether the treatment achieves its intended outcome - **Effectiveness**; to what extent does the treatment achieve its intended outcome - **Efficiency (cost-effectiveness)**; the additional cost/saving associated with the new treatment compared with the additional health benefits versus that of the previous/next best treatment

Question 26

**Where to find evidence when assessing whether to fund a new treatment;** - Safety; Medicines and Healthcare products Regulatory Agency (MHRA), European Medicines Agency (EMA) - Efficacy; National Institute for Health and Care Excellence (NICE), Medline, Cochrane Database - **Effectiveness; [...]** - Efficiency (cost-effectiveness); National Institute for Health and Care Excellence (NICE), Scottish Medicines Consortium (SMC)

Answer 26

**Where to find evidence when assessing whether to fund a new treatment;** - Safety; Medicines and Healthcare products Regulatory Agency (MHRA), European Medicines Agency (EMA) - Efficacy; National Institute for Health and Care Excellence (NICE), Medline, Cochrane Database - **Effectiveness; Clinical Evidence, National Institute for Health and Care Excellence (NICE), Published Randomised Controlled Trials (RCTs)** - Efficiency (cost-effectiveness); National Institute for Health and Care Excellence (NICE), Scottish Medicines Consortium (SMC)

Question 27

**Where to find evidence when assessing whether to fund a new treatment;** - Safety; Medicines and Healthcare products Regulatory Agency (MHRA), European Medicines Agency (EMA) - Efficacy; National Institute for Health and Care Excellence (NICE), Medline, Cochrane Database - Effectiveness; Clinical Evidence, National Institute for Health and Care Excellence (NICE), Published Randomised Controlled Trials (RCTs) - **Efficiency (cost-effectiveness); [...]**

Answer 27

**Where to find evidence when assessing whether to fund a new treatment;** - Safety; Medicines and Healthcare products Regulatory Agency (MHRA), European Medicines Agency (EMA) - Efficacy; National Institute for Health and Care Excellence (NICE), Medline, Cochrane Database - Effectiveness; Clinical Evidence, National Institute for Health and Care Excellence (NICE), Published Randomised Controlled Trials (RCTs) - **Efficiency (cost-effectiveness); National Institute for Health and Care Excellence (NICE), Scottish Medicines Consortium (SMC)**

Question 28

**Where to find evidence when assessing whether to fund a new treatment;** - **Safety; [...]** - Efficacy; National Institute for Health and Care Excellence (NICE), Medline, Cochrane Database - Effectiveness; Clinical Evidence, National Institute for Health and Care Excellence (NICE), Published Randomised Controlled Trials (RCTs) - Efficiency (cost-effectiveness); National Institute for Health and Care Excellence (NICE), Scottish Medicines Consortium (SMC)

Answer 28

**Where to find evidence when assessing whether to fund a new treatment;** - **Safety; Medicines and Healthcare products Regulatory Agency (MHRA), European Medicines Agency (EMA)** - Efficacy; National Institute for Health and Care Excellence (NICE), Medline, Cochrane Database - Effectiveness; Clinical Evidence, National Institute for Health and Care Excellence (NICE), Published Randomised Controlled Trials (RCTs) - Efficiency (cost-effectiveness); National Institute for Health and Care Excellence (NICE), Scottish Medicines Consortium (SMC)

Question 29

**Where to find evidence when assessing whether to fund a new treatment;** - Safety; Medicines and Healthcare products Regulatory Agency (MHRA), European Medicines Agency (EMA) - **Efficacy; [...]** - Effectiveness; Clinical Evidence, National Institute for Health and Care Excellence (NICE), Published Randomised Controlled Trials (RCTs) - Efficiency (cost-effectiveness); National Institute for Health and Care Excellence (NICE), Scottish Medicines Consortium (SMC)

Answer 29

**Where to find evidence when assessing whether to fund a new treatment;** - Safety; Medicines and Healthcare products Regulatory Agency (MHRA), European Medicines Agency (EMA) - **Efficacy; National Institute for Health and Care Excellence (NICE), Medline, Cochrane Database** - Effectiveness; Clinical Evidence, National Institute for Health and Care Excellence (NICE), Published Randomised Controlled Trials (RCTs) - Efficiency (cost-effectiveness); National Institute for Health and Care Excellence (NICE), Scottish Medicines Consortium (SMC)

Question 30

Outline the population-specific factors that need to be taken into account by healthcare funding bodies when deciding whether or not to fund a new treatment? (6)

Answer 30

- What is the likely **demand** for the healthcare resource - Do **resources exist locally** to provide such healthcare resource - What are the **opportunity costs** associated with offering such healthcare resource - Do **other CCGs offer** the healthcare **resource** and if so, how effective is it - Would a decision to fund/not fund be **equitable** (does the healthcare problem effect all individuals within a population equally - How does the decision to fund **accord with** the **views** of the local population

Question 31

Which piece of statutory legislation outlines the types of discrimination that are prohibited by law?

Answer 31

Section 149 of the Equality Act (2010)

Question 32

Outline the specific types of discrimination that are prohibited by law under Section 149 of the Equality Act (2010)? (8)

Answer 32

- Age - Disability - Gender - Pregnancy/maternity - Race - Religion/belief - Sex - Sexual orientation.

Question 33

Outline the responsibilities of the NHS and other public bodies as indicated by Section 149 of the Equality Act (2010)?

Answer 33

Public bodies have a due regard to **eliminate discrimination** and **advance equality of opportunity** between persons who share a relevant protected characteristics and persons who do not

Question 34

Is there any legal framework prohibiting discrimination based on financial state?

Answer 34

**No**; there is no statutory legislation stating that this is illegal

Question 35

Outline the main components to a focussed clinical question? (4)

Answer 35

**PICO**; - **P**opulation; which population of patients should be studied - **I**ntervention; which intervention, treatment or approach should be used - **C**omparison; what are the alternatives to the intervention being considered - **O**utcome; which outcomes should be measured and how

Question 36

Outline the structure and function of an ecological study? (4)

Answer 36

- **Observational descriptive** study - Conducted at the **population level** - Assesses **geographic correlation** - **Generate hypotheses** as to the explanatory variable that governs the observed difference

Question 37

What is meant by the term '**ecological fallacy**'?

Answer 37

Specific problem associated with ecological studies where an **apparent association** between exposure and outcome is **true** at the **population level** but **not necessarily true** at the **individual level**

Question 38

Which type of bias are ecological studies particularly subject to?

Answer 38

**Aggregation bias**; a type of information bias whereby aggregated data can show an effect at the population level that is the opposite to the effect seen at the individual level

Question 39

Outline the structure and function of a cross-sectional trial? (3)

Answer 39

- Observational **analytical** or observational **descriptive** - Single examination of a population at one point in time (**snapshot**) - Looks at **attitudes, behaviours**, health conditions or **risk factors** - Can be **repeated** at subsequent timepoints to measure the change in the population over time

Question 40

With regards to a cross-sectional trial, what is meant by a '**sampling frame**'?

Answer 40

A list of all those within the target population from which inviduals can be selected to act as subjects forming a sample of that population

Question 41

Outline the main subtypes of a cross-sectional study? (2)

Answer 41

- **Descriptive**; measuring only **one parameter** in the target population at a single timepoint - **Analytical**; measuring a **single exposure** and a **single outcome** in the target population at a single timepoint

Question 42

What is the main disadvantage of an analytical cross-sectional study?

Answer 42

**Temporality**; it is impossible to determine if the outcome developed before or after the exposure occurred

Question 43

Outline the structure and function of a case-control study? (3)

Answer 43

- **Analytical** observational trial - **Retrospective**; outcome has already occurred within a target population - **Data** is **collected** on the **exposure** of individuals within that population with the outcome (cases) and those without the outcome (controls)

Question 44

What is assessed when comparing between cases and controls in a case control study? (2)

Answer 44

- The **prevalence** (p) of the **risk factor** (exposure) of interest amongst cases and controls - The **influence** of the **risk factor** (exposure) of interest on the outcome

Question 45

How is information about the exposure gathered from the population in a case-controlled study?

Answer 45

By means of questionnaire

Question 46

Outline the main issues associated with case-control studies? (4)

Answer 46

- **Selection of cases**; a clear definition of individuals that qualify for selection as 'cases' is needed - **Selection of controls**; controls need to be selected from a population as similar as possible to the population from which the cases were selected - **Reverse causality**; additional studies are required to prove temporality and determine if the exposure preceded the outcome or not - **Bias**; in order to ascertain the exposure and outcome, bias must be minimised

Question 47

Which two types of bias are particularly important in case-control studies? (2)

Answer 47

- **Recall bias**; individuals with an outcome are more likely to remember an exposure compared to those without the outcome - **Observer bias**; where the observer is more likely to look for an exposure in an individual if they already know the outcome in that individual

Question 48

What process needs to be carried out in case-control studies to control for any potential confounding factors?

Answer 48

**Matching** of cases and controls based on age, sex, and other relevant and potentially confounding factors

Question 49

Outline the main advantages of case-control studies? (4)

Answer 49

- Useful for **rare outcomes** - Can examine **multiple exposures** - Useful for outcomes with **long latency** - **Quick** and **inexpensive**

Question 50

Outline the main disadvantages of case-control studies? (4)

Answer 50

- **Rely** on **recall/records** to determine exposure - **Difficult** to **identify controls** - Heavily influenced by **confounders** - **Information** (recall and observer) **bias**

Question 51

Outline the main advantages of cohort studies? (4)

Answer 51

- **Ethically** safe - Subjects can be **matched** - Can identify **temporal relationships** - Can directly **measure** outcome (**incidence**)

Question 52

Outline the main disadvantages of cohort studies? (4)

Answer 52

- **Inefficient** for **rare outcomes** - Influence of hidden **confounders** - **Controls** may be **difficult** to **identify** - Validity affected by **follow-up**

Question 53

Outline the main advantages of interventional studies such as randomised controlled trials (RCTs)? (3)

Answer 53

- **Randomisation** minimises effect of **confounders** - **Blinding** eliminates **information bias** - Can demonstrate **causality**

Question 54

Outline the main disadvantages of interventional studies such as randomised controlled trials (RCTs)? (3)

Answer 54

- **Expensive** and **time-consuming** - Can be **unethical** - **Volunteer bias**

Question 55

Outline the main advantages of cross-sectional studies? (2)

Answer 55

- **Cheap** and **simple** - **Ethically** safe

Question 56

Outline the main disadvantages of cross-sectional studies? (2)

Answer 56

- **Cannot establish causality** - **Recall bias**

Question 57

Outline the main difference between a case-control study and a cohort study? (2)

Answer 57

- **Case-control study**; the **outcome** of interest has **already occurred**, cases and controls defined by whether they have the outcome of interest or not - **Cohort study**; the **outcome** of interest has **not** already **occurred**, cases and controls defined by whether they were exposed to the risk factor or not

Question 58

Outline the main similarity and main difference between prospective and retrospective cohort studies? (2)

Answer 58

- **Similarity**; in both, the **outcome** of interest has **not** yet **occurred** - **Difference**; in **retrospective** cohort studies, the **exposure** has **already occurred** whereas in prospective cohort studies, it has not

Question 59

Outline the main issues associated with cohort studies? (4)

Answer 59

- **Selection**; case and control groups need to be as similar as possible apart from the exposure being investigated - **Non-participation**; only a proportion of those eligible actually participate, these participants may differ from non-participants in terms of health behaviours - **Follow-up**; loss to follow-up can influence conclusions, this can be related to exposure, outcome or both - **Data collection**; exposure and/or outcome data must be collected as objectively as possible in order to minimise measurement bias

Question 60

Outline the main advantages of ecological studies? (2)

Answer 60

- Can assess **geographical correlation** - Good for **generating hypotheses**

Question 61

Outline the main disadvantages of ecological studies? (2)

Answer 61

- **Ecological fallacy** - **Aggregation bias**

Question 62

What is the main type of primary intervention study?

Answer 62

Randomised controlled trial (RCT)

Question 63

Outline the key principles in the design of primary intervention trials? (4)

Answer 63

- **Randomisation**; the allocation of subjects to different treatment groups based on chance - **Blinding**; the extent to which the investigators, participants and analysts are aware of which subjects are allocated to which treatment groups - **Follow-up**; inclusion of clear final outcomes at the end-point of the trial for both treatment groups - **Equal treatment**; identical treatment of both groups with the only exception being the experimental treatment

Question 64

Outline the types of randomised controlled trial blinding? (3)

Answer 64

- **Single blinding**; participants do not know which treatment they receive - **Double blinding**; participants and investigators do not know which treatment is being received - **Triple blinding**; participants, investigators and analysers do not know which treatment is being received

Question 65

What is the benefit of single blinding?

Answer 65

Eliminates the placebo effect and recall bias

Question 66

What is the benefit of double blinding?

Answer 66

Eliminates the placebo effect, recall bias and observer bias

Question 67

What is the benefit of triple blinding?

Answer 67

Eliminates the placebo effect, recall bias, observer bias and assessment bias

Question 68

What is meant by '**intention to treat analysis**'?

Answer 68

Method of analysis used in randomised controlled trials (RCTs) where **all individuals within** the **treatment group** at the start of the trial are **analysed together regardless** of whether or not they changed treatment groups or **dropped out** of the trial

Question 69

Outline the benefit of carrying out an intention to treat analysis?

Answer 69

**Preserves** the **baseline comparability** between treatment groups which **guards against bias** that would be introduced where changes to protocol/subject dropout would influence the outcome

Question 70

Outline the definition of the number needed to treat (NNT)?

Answer 70

The number of individuals, on average, that need to be treated in order for the treatment to produce one additional successful outcome

Question 71

Outline the definition of the number needed to harm (NNH)?

Answer 71

The number of individuals, on average, that need to be treated in order for the treatment to produce one additional adverse outcome

Question 72

Outline the three components to consider when critically analysing research? (3)

Answer 72

- **Results**; what the conclusion of the research is - **Validity;** how trustworthy the research is - **Relevance**; how useful the research is

Question 73

What is meant by the term '**systematic review**'?

Answer 73

A review of all the literature on a particular topic, which has been systematically identified, appraised and summarised giving a summary answer

Question 74

Outline the features of a good systematic review? (5)

Answer 74

- Asking a **clear** and **focussed question** - **Clearly defined** inclusion and exclusion **criteria** - **Reproducibility** - **Appraisal** of included studies - Assessment of **publication bias**

Question 75

What kind of analysis can be used to assess whether a systematic review is affected by publication bias?

Answer 75

**Funnel Plot**; if publication bias is present, then smaller studies with negative results (control better than treatment) are likely to be missing, making the funnel plot appear asymmetrical

Question 76

What is meant by the term '**meta-analysis**'?

Answer 76

A statistical technique for **quantitatively** pooling the results of individual studies

Question 77

How are the results of a meta-analysis typically displayed?

Answer 77

As a **Forrest Plot** (blobbogram)

Question 78

Outline some of the typical causes of heterogeneity that prevents the inclusion of different studies as part of a meta-analysis? (5)

Answer 78

- **Chance** - Clinical **differences** in **treatment regimens** between trials - **Different** measured **outcomes** - **Different populations** - **Methodological differences** between trials

Question 79

What scoring system can be used to rate the quality of evidence for a particular outcome across studies within a systematic review?

Answer 79

Grading of Recommendations Assessment, Development and Evaluation (GRADE)

Question 80

What features are assessed as part of the GRADE system of evidence classification? (5)

Answer 80

- **Study limitations**; risk of bias - **Inconsistency**; heterogeneity of treatment effects across different studies - **Indirectness**; degree of differences between studies - **Imprecision**; random error - **Publication bias**; selection of publications for review

Question 81

Outline the tiers of the GRADE system of evidence rating? (4)

Answer 81

- **High quality**; further research **unlikely to change confidence** in the estimate of effect - **Moderate quality**; further research **likely to have an impact on confidence** in the estimate of effect - **Low quality**; further research **likely to have an impact on confidence** and/or **change the estimate** of effect - **Very low quality**; further research is needed as current **estimate of effect** is very **uncertain**

Question 82

What is meant by the term '**demographic transition**'?

Answer 82

Demographic transition describes the changing age structure that exists within a population as that population progresses through stages of development

Question 83

What is a population pyramid?

Answer 83

A population pyramid is a histogram of age distribution across both sexes within a population that can indicate the stage of development that the observed population is in

Question 84

What is meant by the term '**epidemiological transition**'?

Answer 84

Epidemiological transition describes the shift in the predominant contribution to morbidity and mortality from infectious disease and malnutrition early in population development to that of non-communicable diseases and cancer in developed populations

Question 85

Which parameter is considered the most sensitive indicator of population development?

Answer 85

**Infant mortality rate (IMR)**; the number of deaths occurring < 1 year of age per 1000 live births

Question 86

Outline the main types of screening? (3)

Answer 86

- **Primary**; screening that aims to **prevent** a **disease** from **occurring** (e.g. vaccinations) - **Secondary**; screening that aims to **detect** a **disease** at an **early** enough **stage** to allow intervention (e.g. bowel cancer FIT testing) - **Tertiary**; screening for **complications** of a **disease** that has **already developed** (e.g. diabetic eye screening)

Question 87

Describe the inclusion criteria for the screening of genetic diseases after birth?

Answer 87

Newborns typically day 5-7 of life

Question 88

Describe the inclusion criteria for the screening of abdominal aortic aneurysms (AAAs)? (2)

Answer 88

- All men > 65 years - Women > 70 with risk factors

Question 89

Describe the inclusion criteria for the screening of bowel cancer using the faecal immunochemical test (FIT)?

Answer 89

All patients aged **60-74 years** every 2 years and followed-up with a **colonoscopy if positive**

Question 90

Describe the inclusion criteria for the screening of breast cancer? (2)

Answer 90

- **Most women**; mammogram (X-ray) or breast ultrasound every 3 years from age 50-70 - **Women with family history of breast or ovarian cancer**; mammogram (X-ray) or breast ultrasound every 3 years from age 40

Question 91

Describe the inclusion criteria for the screening of cervical cancer? (3)

Answer 91

- **Women aged 25-49**; every 3 years - **Women aged 50-64**; every 5 years - **Women 65+**; only if 1 of the last 3 tests were abnormal

Question 92

Describe the inclusion criteria for the screening of fetal anomalies during pregnancy?

Answer 92

Pregnant women at 20 weeks gestation

Question 93

Outline the two main sets of criteria that set out the principles of screening tests? (2)

Answer 93

- Wilson and Junger criteria - UK National Screening Committee (NSC) criteria

Question 94

Outline the key components that make up the UK National Screening Committee (NSC) Criteria for suitable screening programmes? (4)

Answer 94

- **Condition**; important health problem, identifiable in early stages - **Test**; simple, safe and validated screening test - **Treatment**; evidence of early intervention producing better outcomes - **Programme**; evidence that the proposed programme is effective

Question 95

Outline the main sources of bias affecting screening programmes? (3)

Answer 95

- **Lead-time bias**; screening increases the perceived survival time without actually affecting the course of the disease - **Length-time bias**; diseases with a long-latent time are more likely to be detected by screening than those with a short-latent time - **Volunteer bias**; those who accept invitations to be screened are more likely to be those at lower risk and healthier generally

Question 96

Outline the main advantages associated with screening programmes? (2)

Answer 96

- **Cost-effective** by preventing disease - **Better outcomes** as **intervention** possible at an **earlier** stage

Question 97

Outline the main disadvantages associated with screening programmes? (5)

Answer 97

- Health-related **anxiety** - **Overdiagnosis** and overtreatment - Detected disease may never have caused a problem in the first-place (**incidentalomas**) - **False reassurance** if screening negative - Requires large **investment** and **infrastructure**

Question 98

What can be inferred if a diagnostic test has a high sensitivity? (3)

Answer 98

- Low false negative - Highly likely that the test will be positive given the presence of the disease - A negative test result effectively rules out the disease

Question 99

What can be inferred if a diagnostic test has a high specificity? (3)

Answer 99

- Low false positive - Highly likely that the test will be negative given the absence of the disease - A positive test result effectively rules in the disease

Question 100

In the context of diagnostic testing, what is meant by the term '**sensitivity**' (S_e)?

Answer 100

Sensitivity (S_e) describes the probability of a diagnostic test being positive given the presence of disease

Question 101

In the context of diagnostic testing, what is meant by the term '**specificity**' (S_p)?

Answer 101

Specificity (S_p) describes the probability of a diagnostic test being negative given the absence of disease

Question 102

In the context of diagnostic testing, what is meant by the term '**positive predictive value**' (PPV)?

Answer 102

Positive predictive value (PPV) describes the probability of the disease being present if the test is positive

Question 103

In the context of diagnostic testing, what is meant by the term '**negative predictive value**' (NPV)?

Answer 103

Negative predictive value (NPV) describes the probability of the disease being absent if the test is negative

Question 104

Give examples of systems used to measure population health? (5)

Answer 104

- Life expectancy at birth - Healthy life expectancy - Disability-adjusted Life years (DALYs) - Fertility rates - Infant mortality rates

Question 105

Outline the key factors for consideration in the context of setting priorities of a healthcare resource? (5)

Answer 105

- **Equity**; are there avoidable or remedial differences amongst different groups in terms of access to this healthcare resource - **Efficacy**; whether the healthcare resource achieves its intended beneficial outcome - Effectiveness; what extent does the healthcare resource achieve its intended outcome - **Efficiency**; the benefit of a healthcare resource in relation to the effort expended to provide such a resource - **Opportunity cost**; the cost incurred as a result of not using that healthcare resource for its next most valued use

Question 106

How can you determine the cost effectiveness of a healthcare resource?

Answer 106

Carry out a cost-effectiveness analysis

Question 107

In the context of healthcare resource provision, what is an '**economic evaluation**'?

Answer 107

An economic evaluation is a **comparative analysis** of **alternative courses of action** in response to a healthcare problem in terms of their **costs and consequences**

Question 108

Outline the main challenges faced by the national health service (NHS) in regard to resource allocation? (4)

Answer 108

- Finite resources - Balancing equality of access and equality of outcome - Cost-effectiveness - Political turbulence and associated priorities of public spending

Question 109

Outline the main approaches that are used to ration resources in the NHS? (4)

Answer 109

- **Exclusion**; not funding certain healthcare resources - **Dilution**; increasing number of appointments by shortening their length - **Termination**; discharging earlier than what would be desirable - **Delay**; use of waiting lists

Question 110

Which bodies are responsible for deciding how healthcare resources are allocated in the UK at the national, local and individual level? (3)

Answer 110

- **National level**; the treasury, department of health (DoH), National Institute for Health and Care Excellence (NICE) - **Local level**; clinical commissioning groups (CCGs), local authorities (LAs) - **Individual level**; hospitals, clinicians

Question 111

Outline the main types of healthcare evaluation? (3)

Answer 111

- **Outcome/effectiveness evaluation**; assesses whether a healthcare intervention is effective/achieves its intended goals - **Economic evaluation**; considers whether a healthcare intervention is cost-effective - **Process evaluation**; assesses whether the components of a healthcare intervention function as expected

Question 112

What aspect of a healthcare evaluation process can increase its effectiveness?

Answer 112

If the evaluation is done **prospectively** and **built into** the healthcare **service** from the outset

Question 113

Outline the key domains used to help evaluate a healthcare resource? (7)

Answer 113

- **Effectiveness**; whether and to what extent a healthcare resource achieves its intended goals - **Safety**; whether a healthcare resource causes adverse effects or harms - **Efficiency (cost-effectiveness)**; the additional cost/saving associated with the healthcare resource compared with the additional health benefits versus that of the previous/next best alternative - **Equity**; whether a healthcare resource is judged as fair - **Accessibility**; whether those in need of the healthcare resource can access the service - **Quality**; whether a healthcare resource achieves intended non-clinical goals and establishes an adequate process of care - **Satisfaction**; the service users' overall judgement of the healthcare resource

Question 114

Outline the key domains that make up Donabedian's framework for healthcare service evaluation? (4)

Answer 114

- **Structure**; evaluation of appropriate delivery **facilities, staffing and equipment** - **Process**; evaluation of **everything done to the patient** as part of the provision of the healthcare resource - **Outputs**; the **number** of **cases identified** and **individuals** successfully **accessing** the healthcare resource - **Outcomes**; additional **health-related gains** as a result of the healthcare resource

Question 115

What is meant by the term '**clinical governance**'?

Answer 115

Clinical governance describes the framework through which **healthcare providers** and their **staff** are held **accountable** for the **quality** of patient **care**

Question 116

Outline the components that make up clinical governance framework? (6)

Answer 116

- **Audits** of practice - **Appraisals** - **Revalidation** - Regular **departmental meetings** to highlight concerns - Clear routes of **accountability** for staff - **Risk management structure** (e.g. Datix) - Complaints and Patient Advice and Liaison Service (**PALS**)

Question 117

Which four domains of a doctor's performance can be assessed? (4)

Answer 117

- **Knowledge**; up-to-date understanding of the information required for them to do their job - **Skills**; continued demonstration of clinical capabilities - **Attitudes**; professionalism, respect for patients, probity and self-scrutiny - **Systems**; continued professional development (CPD), record-keeping, revalidation

Question 118

Outline the idea surrounding the ‘**prevention paradox**’ suggested by Rose (2008)?

Answer 118

**Prevention paradox**; a preventative measure that brings about **large benefits** for the **population** offers **little benefit** to each participating **individual**

Question 119

Outline the key levels at which healthcare and good health can be promoted? (5)

Answer 119

- Interventions aimed at the **individual** - **Local community** actions; media campaigns, warning signs, information leaflets - Providing **supportive environments**; infrastructure, legislation - Healthy **public policy**; minimal alcohol pricing, indoor smoking bans - Reorientation of **healthcare** services; healthcare services tackling key problems in high-risk groups

Question 120

Outline what is meant by the term '**primary prevention**' of disease?

Answer 120

Primary prevention; aims to **prevent disease developing** in the first instance

Question 121

Outline what is meant by the term '**secondary prevention**' of disease?

Answer 121

Secondary prevention; aims to **reduce **the** severity** and/or **prevent recurrence** of disease once it has developed

Question 122

Outline what is meant by the term '**tertiary prevention**' of disease?

Answer 122

Tertiary prevention; aims to **reduce the consequences** of an established disease

Question 123

Give an example of a primary disease prevention measure?

Answer 123

**Immunisation** against communicable diseases

Question 124

Give an example of a secondary disease prevention measure?

Answer 124

Screening programmes

Question 125

Give an example of a tertiary disease prevention measure?

Answer 125

Rehabilitation programmes

Question 126

Outline the difference between a targeted approach and a population approach to disease prevention? (2)

Answer 126

- **Targeted approach**; aims to target disease prevention in high-risk groups to reduce individual risk but no substantial effect on the risk in the general population - **Population approach**; universal prevention measures reduces the proportion of people above the treatment threshold and therefore the risk of disease amongst the general population, although also reducing the amount of people which benefit from the prevention

Question 127

Outline some of the main ways by which healthcare services are improved? (5)

Answer 127

- **Revalidation**; regulation of professionals providing that service - **Inspection**; regulation of healthcare-providing premises - **Education**; increasing knowledge of up-to-date evidence - **Setting standards/targets**; realistic goals encourage development - **Clinical guideline information**; evidence-based practise

Question 128

Outline the domains that make up the healthcare commissioning cycle? (4)

Answer 128

- Plan - Do - Review - Analyse

Question 129

Outline the three main domains that make up the determinants of health? (3)

Answer 129

- **Lifestyle determinants**; smoking, alcohol, diet, exercise - **Social determinants**; education, economic background, employment - **Environmental determinants**; air quality, water quality, sanitation, food availability

Question 130

Give examples of some of the commonly used socioeconomic deprivation indicators? (3)

Answer 130

- Townsend deprivation score (TDS) - Index of multiple deprivation (IMD) - National Statistics Socio-Economic classification (NS-SEC)

Question 131

Outline the purpose and function of a health needs assessment (HNA)?

Answer 131

Assessments that are conductive to **inform the development** of **services** so as to **determine** if a health problems **can be addressed** by an effective intervention or service provision

Question 132

When does a healthcare problem become a healthcare need?

Answer 132

If it has the potential to benefit from an intervention

Question 133

Outline the three main components that make up a **health needs assessment** (HNA) according to the Stevens, Rafferty and Mant model? (3)

Answer 133

- **Assessment** of the size of the **population** and the incidence and prevalence of that healthcare problem - **Assessment** of the **current service** provisions for prevention and treatment of that healthcare problem - **Review** of the **current evidence** for the effectiveness and cost-effectiveness of the **proposed intervention**

Question 134

Outline the epidemiological triad of factors that affect disease transmission? (3)

Answer 134

- **Host**; the innate susceptibility of the affected individual - **Agent**; the innate infectiousness of the causative agent - **Environment**; the factors that increase the chances of transmission

Question 135

What is meant by the term '**basic reproductive number**' (R₀)?

Answer 135

The basic reproductive number (R₀) is the number of new cases that occur in a totally susceptible population

Question 136

What is meant by the term '**effective/net reproductive number**' (R_n)'?

Answer 136

The effective/net reproductive number (R_n) is the number of new cases that occur in a population where they may be both susceptible and immune people presence

Question 137

What needs to happen to the value of the effective/net reproductive number (R_n) in order for disease transmission to stop?

Answer 137

It must drop below 1 meaning that each new case infects less than 1 other individual

Question 138

Outline the two main definitions of a disease outbreak? (2)

Answer 138

- Where **≥ 2 people** who **experience a similar illness** or **confirmed infection** are linked by a common factor - Where an **observed** number of **cases** of an illness or confirmed infection **exceed** what would be **expected** for a given place and time

Question 139

Outline the key attributes of effective disease surveillance? (6)

Answer 139

**PAC³T**; - **P**ractical - **A**ccurate - **C**ontinuous - **C**onsistent - **C**omplete - **T**imely

Question 140

What is the definition of communicable disease surveillance?

Answer 140

The conintued scrutiny of all aspects of a disease occurance and spread that are amenable to effective control

Question 141

What is the main requirement when a notifiable disease is suspected?

Answer 141

Public Health England (PHE) must be informed **within 3 days** where there is a clinical **suspicion** or **verbally within 24 hours** if the case is **confirmed** and urgent

Question 142

What type of trial design is considered the gold-standard for interventional trials?

Answer 142

Randomised controlled trials (RCTs)

Question 143

What is meant by '**type 1 error**' (α)?

Answer 143

Type 1 error (α) refers to the **incorrect rejection** of a **true null hypothesis**, otherwise referred to as a **false positive**

Question 144

What is meant by **type 2 error** (β)?

Answer 144

Type 2 error (β) refers to the **failure** to **reject** a **false null hypothesis**, otherwise referred to as a **false negative**

Question 145

What is the main factor that influences the type 2 error (β) and thus power of a study?

Answer 145

**Sample size**; smaller sample sizes will have a greater type 2 error (β) and therefore diminished power

Question 146

Outline the current Public Health England (PHE) list of notifiable diseases? (34)

Answer 146

- Acute encephalitis - Acute infectious hepatitis - Acute meningitis - Acute poliomyelitis - Anthrax - Botulism - Brucellosis - Cholera - COVID-19 - Diphtheria - Enteric fever (typhoid or paratyphoid fever) - Food poisoning - Haemolytic uraemic syndrome (HUS) - Infectious bloody diarrhoea - Invasive group A β-haemolytic streptococcal disease - Legionnaires’ disease - Leprosy - Malaria - Measles - Meningococcal septicaemia - Monkeypox - Mumps - Plague - Rabies - Rubella - Severe Acute Respiratory Syndrome (SARS) - Scarlet fever - Smallpox - Tetanus - Tuberculosis - Typhus - Viral haemorrhagic fever (VHF) - Whooping cough - Yellow fever

Question 147

Outline the obligation of healthcare professionals to disclose a new diagnosis of a notifiable disease to Public Health England (PHE)?

Answer 147

There is a **statutory legal obligation** for healthcare professionals to disclose cases of notifiable diseases under **Section 3 of the Infectious Diseases Act (1889)**

Question 148

What is meant by the term '**odd's ratio**' (OR)?

Answer 148

The odds ratio (OR) is a ratio of the odds of exposure in cases to the odds of exposure in controls.

Question 149

Outline the benefits of matching cases and controls in case-control studies? (2)

Answer 149

- **Balances** the key **confounders** between the two groups - This will mean that these **confounding variables can be excluded** when considering any associations observed

Question 150

Which type of study design is the only one in which causality can be inferred?

Answer 150

Interventional studies such as randomised controlled trials (RCTs)

Question 151

What is the key difference between a systematic review and a meta analysis? (2)

Answer 151

- Systematic review **may or may not** include a **statistical** combination of the results from the various studies reviewed - Meta analysis **always** involves a **statistical** combination and the production of a combined estimate of results.

Question 152

What is the root cause of publication bias in meta-analyses and systematic reviews?

Answer 152

Difficulty in including data from studies that have not been published

Question 153

What is the mathematical definition of '**relative risk**' (RR)?

Answer 153

Relative risk (RR); the ratio of the incidence of the outcome of interest in the exposed group compared to the incidence of the outcome of interest in the unexposed group

Question 154

What can be inferred if a diagnostic test has a low sensitivity? (3)

Answer 154

- High false negative - Not unlikely that the test will be negative despite presence of the disease - A negative test result does not effectively rule out the disease

Question 155

What can be inferred if a diagnostic test has a low specificity? (3)

Answer 155

- High false positive - Not unlikely that the test will be positive despite the absence of the disease - A positive test result does not effectively rule in the disease

Question 156

Outline the two main types of study design? (2)

Answer 156

- **Observational studies**; where the investigator(s) observe a natural occurrence - **Interventional studies**; where the investigator(s) intervene actively

Question 157

Give examples of observational studies? (5)

Answer 157

- Cohort studies - Case-control studies - Cross-sectional studies - Case reports/series - Ecological studies

Question 158

Give examples of interventional studies? (2)

Answer 158

- Randomised controlled trials (RCTs) - Non-randomised trials

Question 159

Which three factors need to be considered before determining a causal relationship? (3)

Answer 159

- Chance - Bias - Confounding

Question 160

Which parameter is calculated as a result of direct standardisation when looking at mortality rates?

Answer 160

Directly age-standardised rate (DASR)

Question 161

What parameter is calculated in a case-control study in order to quantify the magnitude of the influence of the risk factor (exposure) on the outcome?

Answer 161

Calculating the odds and odds ratio (OR) between the case and control populations

Question 162

Denoting risk; - Case-control studies; **[...]** as the outcome has already occurred - Cohort studies; use both the odds ratio (OR) and the relative risk (RR) as the outcome has not occurred

Answer 162

Denoting risk; - Case-control studies; **use only the odds ratio (OR)** as the outcome has already occurred - Cohort studies; use both the odds ratio (OR) and the relative risk (RR) as the outcome has not occurred

Question 163

Denoting risk; - Case-control studies; use only the odds ratio (OR) as the outcome has already occurred - Cohort studies; **[...]** as the outcome has not occurred

Answer 163

Denoting risk; - Case-control studies; use only the odds ratio (OR) as the outcome has already occurred - Cohort studies; **use both the odds ratio (OR) and the relative risk (RR)** as the outcome has not occurred

Question 164

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - OR = 1; the exposure does not affect the odds of the outcome - **[...]**; the exposure increases the odds of the outcome

Answer 164

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - OR = 1; the exposure does not affect the odds of the outcome - **OR > 1**; the exposure increases the odds of the outcome

Question 165

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - **[...]**; the exposure does not affect the odds of the outcome - OR > 1; the exposure increases the odds of the outcome

Answer 165

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - **OR = 1**; the exposure does not affect the odds of the outcome - OR > 1; the exposure increases the odds of the outcome

Question 166

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - OR = 1; the exposure does not affect the odds of the outcome - OR > 1; **[...]**

Answer 166

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - OR = 1; the exposure does not affect the odds of the outcome - OR > 1; **the exposure increases the odds of the outcome**

Question 167

Odds Ratio (OR) Interpretation - OR < 1; **[...]** - OR = 1; the exposure does not affect the odds of the outcome - OR > 1; the exposure increases the odds of the outcome

Answer 167

Odds Ratio (OR) Interpretation - OR < 1; **the exposure decreases the odds of the outcome** - OR = 1; the exposure does not affect the odds of the outcome - OR > 1; the exposure increases the odds of the outcome

Question 168

Odds Ratio (OR) Interpretation - **[...]**; the exposure decreases the odds of the outcome - OR = 1; the exposure does not affect the odds of the outcome - OR > 1; the exposure increases the odds of the outcome

Answer 168

Odds Ratio (OR) Interpretation - **OR < 1**; the exposure decreases the odds of the outcome - OR = 1; the exposure does not affect the odds of the outcome - OR > 1; the exposure increases the odds of the outcome

Question 169

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - **[...]**; the exposure does not affect the odds of the outcome - OR > 1; the exposure increases the odds of the outcome

Answer 169

Odds Ratio (OR) Interpretation - OR < 1; the exposure decreases the odds of the outcome - OR = 1; **the exposure does not affect the odds of the outcome** - OR > 1; the exposure increases the odds of the outcome

Question 170

Broadly speaking, what is indicated by the value of the relative risk (RR)?

Answer 170

How many times more likely the exposed group are to develop the outcome than the non-exposed group

Question 171

Broadly speaking, what is indicated by the value of the absolute risk reduction (ARR)?

Answer 171

For every 100 exposed individuals, a number equal to the value of the ARR more inviduals will go on to develop the outcome compared to the number of inviduals who will develop the outcome from a group of 100 non-exposed individuals

Question 172

Broadly speaking, what is indicated by the value of the odds ratio (OR)? (2)

Answer 172

- The greater the value of the odd's ratio (OR) is above 1, the more likely that those with the disease will have been exposed than those without the disease - The greater the value of the odd's ratio (OR) is below 1, the more likely that those without the disease will have been exposed than those with the disease

Question 173

What is meant by the term '**power**'?

Answer 173

The probability of rejecting the null hypothesis if it is false

Question 174

What is meant by the term '**randomisation**'?

Answer 174

The process used in interventional trials where study subjects are randomly allocated by chance to separate groups that recieve different interventions

Question 175

Which equation is used to calculate the number needed to treat (NNT)?

Answer 175

Question 176

Which equation can be used to calculate prevelance?

Answer 176

Question 177

Using the table below, how would you calculate the specificity (S_p) of a diagnostic test?

Answer 177

Question 178

Using the table below, how would you calculate the sensitivity (S_e) of a diagnostic test?

Answer 178

Question 179

Using the table below, how would you calculate the prevalence (P) of a diagnostic test?

Answer 179

Question 180

Using the table below, how would you calculate the positive predictive value (PPV) of a diagnostic test?

Answer 180

Question 181

Using the table below, how would you calculate the negative predictive value (NPV) of a diagnostic test?

Answer 181

Question 182

Using the table below, how would you calculate the relative risk/risk ratio (RR) of the exposed group developing the outcome?

Answer 182

Question 183

Using the table below, how would you calculate the odds ratio (OR) describing the magnitude of the relationship between the exposure and the outcome?

Answer 183

Question 184

Using the table below, how would you calculate the absolute risk reduction (ARR)?

Answer 184

Question 185

Outline the equation used to calculate the power of a study?

Answer 185

Question 186

How can you calculate the effective/net reproductive number (R_n)?

Answer 186

Question 187

What is meant by the term '**screening**'?

Answer 187

Screening is a public health service in which members of a **defined population**, who do **not necessarily perceive they are at risk** of, or are already affected by a disease or its complications, are asked a question or **offered a test**, to **identify** those individuals who are **more likely to be helped than harmed** by further tests or treatment to reduce the risk of a disease or its complications