Public Health Flashcards
Used lectures from 2017-18 and some peer teaching powerpoints
Which model is the most powerful predictor of health experience?
Socio-economic model
What is social class?
A measure of not only occupation but also stratification, social position, access to power and resources
What are the 2 main reports in response to health inequalities?
- The Black Report (1980)
- The Acheson Report (1998)
What does the Black Report look at?
It’s a response to health inequalities.
- Looked at how health standards are directly linked to social class
- Looked at factors such as poor environment, housing, education etc
What is the Acheson Report?
It’s a response to heath inequalities.
- High priority should be given to health of families with children
- All policies likely to have an impact on health should be evaluated in terms of their impact on health inequalities
What is ethics?
Broadly defined as the philosophical study of moral principles of right and wrong actions or ways of living
What are the 3 ethical levels?
Meta-ethics
Ethical theory
Applied ethics
What is meta-ethics?
Explores fundamental questions (can things be right or wrong, what is the good life, etc)
What is ethical theory?
Philosophical attempts to create ethical theories
Virtue Categorical Imperative Utilitarianism 4 principles
What is applied ethics?
Recent emergence of ethical investigation in specific areas eg environmental, medical and PH
What are posible rivals to ethical arguments?
Laws, codes of ethics, religious/cultural beliefs, personal conscience
What is the difference between morals and ethics?
Morals are personal, self-held: everyone can have different morals/beliefs regarding what is right/wrong
whereas
Ethics are often societal and community perceptions about right and wrong
What is utilitarianism?
- Example of consequentialism
- Actions are right if they do the most BENEFIT for the MOST people
What is consequentialism eg utilitarian?
- Actions are ethical based on the CONSEQUENCES of the action
What are virtue ethics?
- Actions are judged based on the CHARACTER of the individual carrying out the action
- Integrates reason and emotion
- Based on the VIRTUES they hold
What is deontology?
- Features of the act themselves determine worthiness
- eg Virtue
Challenge: can duties conflict?
What are the 4 ethical principles?
- Autonomy
- Beneficence
- Non-maleficence
- Justice
What is autonomy?
People have the right to choose what happens to them
What is beneficence?
Do good
What is non-maleficence?
Do no harm
- Ensure your actions do not cause harm
What is justice?
Fairness for all
- Examples include fair distribution of scarce resources, respecting everyone’s human rights etc
What is at the top of the hierarchy for evidence based medicine?
Systematic reviews / meta analysis of RCTs
What is bias?
Systematic error in studies that leads to errors in conclusion or skewed results
Name some types of bias
Observer, measurement, lead-time, publishing
How do you remove bias?
Blinding in studies
What does chance mean?
The observation may not be a true one
What is a confounder?
A factor that independently influences the outcome of a situation, but doesn’t lie on the causal pathway
What are the 2 basic approaches for statistical analysis?
- Estimation (CI)
- Hypothesis testing (p values)
If a CI goes over 0, is it relevant?
No
State the definition of CI (confidence interval)?
A range of values, so defined that the true value probably lies within
What is the usual chosen CI?
95%
if you did the test 100x, 95 are likely to contain true value for the population
State the definition of p-value
The probability of an event occurring, given the null hypothesis is true
(p-value between 0-1)
What is the WHO definition of health?
A state of complete physical, mental and social well-being and not merely the absence of disease or infirmity
What are the key features of PH?
- Health promotion (lifestyles eg change4life campaign, inequalities, education etc)
- Health protection (infectious diseases, env disasters, emergency responses etc)
- Improving services (clinical effectives, audit and evaluation etc)
What is the inverse care law?
Those who need medical care the most are least likely to access
What does primary prevention do?
- Prevents a disease from occurring
What are examples of primary prevention?
Lifestyle changes, water fluoridation, childhood immunisation
What does secondary prevention do?
- Aims to reduce impact of disease - to halter slow disease progession
What are examples of secondary prevention?
- Breast cancer screening, aspirin to prevent further MIs
What does tertiary prevention do?
- Minimises disability (improves quality of life) and prevents complications
What are examples of tertiary prevention?
Rehab post-stroke
What is the difference between primary and secondary screening?
Primary prevents disease OCCURRENCE eg screening to find risk factors
whereas
Secondary detects EARLY disease, to alter the course eg mammography to treat breast cancer early
What is the screening criteria?
Wilson and Junger
Name the Wilson and Junger screening criteria regarding the CONDITION
- Condition should be an important health problem
- Natural history should be well understood
- Should be a detectable early stage
Name the Wilson and Junger screening criteria regarding the TREATMENT
- Should be accepted treatment with the disease
- Facilities for diagnosis/treatment should be available
- Adequate health service provision should exist for those found positive
Name the Wilson and Junger screening criteria regarding the TEST
- Suitable test should exist for early stage
- Test should be acceptable
- Should be repeated
Name the Wilson and Junger screening criteria regarding the RISKS & BENEFITS
- Should be an agreed policy on whom to treat
- Costs should be balanced vs benefits
- Risks (psych/phys) should be less than benefits
How can prevalence be monitored?
Actively (see out ppl with disease)
Passively (taken from data at GP practices or anonymous info)
What is a false positive?
Screening test says they have the disease but they do not upon further testing
What is a false negative?
Screening test says they do not have the disease but they do/will develop
What is sensitivity?
The proportion of people with the disease who are correctly identified by the screening process
= a / a+c
where a = true positive and c = false negative
What is specificity?
The proportion of people without the disease who are correctly excluded by the screening process
= d / b+d
where d = true negative and b = false positive
What is the PPV (positive predictive value?)
Proportion of people who have a positive screening test and do have the disease
- Want this to be high
What is the NPV (negative predictive value?)
Proportion of people with a negative result who do not have the disease following testing
- Want this to be high also
Name some examples of STIs
HIV, gonorrhoea, chlamydia
Name some ways in which sexual health is screened/prevented
HIV testing for mothers, free STI testing, home testing kits, anonymous services
What are the stages in the transtheoretical model (model of change)?
- Precontemplation (not ready/thinking about quitting eg)
- Contemplation (getting ready - thinking about quitting but not quite ready)
- Preparation (ready - taking steps to prepare)
- Action (ex-smoker, quit for <6m)
- Maintenance (non smoker, quit for >6m)
- Relapse?
Name some attempts to reduce smoking prevalence
- Ban of smoking in public places (2005)
- Change in legal ace to buy tobacco prods (2007)
- NHS stop smoking campaign
Why do people smoke?
- Nicotine addiction (withdrawal, tolerance)
- Stress coping mechanism
- Socialising
- Weight loss
What are the 3A’s?
Ask (are you a smoker, ex, etc)
Advise (can help if you want)
Assist (refer to local stop smoking service)
What is the chain of infection?
- Susceptible host
- Causative micro-organism
- Reservoir
- Portal of exit
- Mode of transmission (spread)
- Portal of entry
If you break the chain at any point, infections can be prevented and controlled
What makes somebody a susceptible host?
- Extremes of age
- Those undergoing treatments for disease eg chemotherapy
- Anything which may reduce resistance to infections eg smoking
Name some portals of entry and exit for infection
Respiratory tract, GI tracts, broken skin
What does infection transmission depend on?
- Number of microorganisms spread
- Microorganism stability in environment
- Number of microorganisms need to infect a new host
Name some types of exogenous spread (cross-infection)
- Direct contact eg breast milk, sexual contact
- Indirect contact eg infected surfaces
- Airborne spread eg sneezing/vomiting
What is self spread in regards to infection transmission?
Organisms that live in a specific area can cause infection if moved to another site eg UTI caused by e coli due to proximity of rectum to urethra
What is the purpose of hand decontamination?
- To remove transient hand flora
- To reduce number of resident flora
NB: the microorganisms that occupy a particular body site = resident flora
What are the 3 levels of hand washing?
- Social/routine handwash
- Hygienic hand antisepsis
- Surgical hand scrub
What is health behaviour?
A behaviour aimed to PREVENT DISEASE eg eating healthily
What is illness behaviour?
A behaviour aimed to SEEK REMEDY eg going to the doctor
What is sick role behaviour?
Any activity aimed at GETTING WELL eg taking prescribed medications
Describe the 2 levels of intervention
- Population level - HEALTH PROMOTION
- Individual level - PATIENT CENTRED approach
What is unrealistic optimism?
Individuals continue to practice health damaging behaviour due to inaccurate perceptions of risk and susceptibility
What is the health belief model (Becker)?
Individuals will change if they believe:
- That they are susceptible to the condition
- That it has serious consequences
- That taking action reduces susceptibility
- That benefits outweigh the costs
What is the theory of planned behaviour?
Best predictor of behaviour is INTENTION which is determined by; attitude, social pressure to undertake behaviour, perceived behavioural ability
What is the 90:10 paradox?
Most health activity occurs outside hospitals, but most of our health resources are concentrated in hospitals
What is evidence based medicine (EBM)?
The conscientious, explicit, and judicious use of the best evidence in making decisions about the care of individual patients
(lol what a mouthful)
What are the 5 steps of evidence based practice?
- Asking focused questions
- Finding evidence
- Critical appraisal
- Making a decision
- Evaluating performance
What does PICO stand for?
Patient/Population (under study)
Intervention (exposure/treatment/procedure)
Comparison/Control
Outcome
What is the purpose of critical appraisal?
To assess and consider:
- validity
- reliability
- applicability
What is the difference between external and internal validity?
External = generalisation to the population described whereas internal = does the study measure what it intended to?
What is the relative risk (RR)?
RR = how many times more likely it is that an event will occur in intervention group vs control group
RR = 1 (no difference between 2 groups)
RR >1 (intervention increased the risk of outcome)
RR <1 (intervention decreased the risk of outcome)
What is relative risk reduction (RRR)?
RRR = reduction in rate of the outcome in the intervention group vs the control group
What is absolute risk reduction (ARR)?
ARR = absolute difference in the rates of events between the 2 groups and gives an indication of the baseline risk and intervention effect
What is the number needed to treat (NNT)?
NNT tells us the number of patients we need to treat to prevent 1 bad outcome
How is NNT calculated?
1/ARR (when ARR = decimal)
or 100/ARR (when ARR = %)
What is sociology’s aims?
To understand interactions between individuals and social structures
Name some determinants of health
Social class, unemployment, racial discrimination
Briefly discuss the biomedical model
Our body is a machine that can be repaired. Privileges use of technology. Neglects social/psych dimensions of disease. Mind and body are treated separately
“Aspects of normal life become the focus of medical expertise and intervention”
What is this term?
Medicalisation
What are the 4 awareness contexts in relation to death?
- Closed awareness
- Suspicion awareness
- Mutual awareness
- Open awareness
What are the 4 awareness contexts in relation to death?
- Closed awareness
- Suspicion awareness
- Mutual awareness
- Open awareness
What is “death the hospice way”?
Open awareness, MDT, emotions and relationships, holistic care
What kind of a process is dying?
Not only biological - also social and relational
What are the duties of a doctor according to the GMC?
- Patient care must be 1st concern
- Protection/promotion of health of patients and public
- Good standard of care
- Professional knowledge/skills should be kept up to date
- Work in limits of competence
- Work with colleagues in ways that best service patient interests
- Treat patients as individuals, respect their dignity
Define confidentiality
A set of rules or a promise that limits access or places restrictions on certain types of info
Why should patient info remain confidential?
- May be reluctant to seek attention
- May not divulge important info
- Basis of a trusting relationship
When is disclosure allowed?
- If required by law
- If patient consent is obtained (explicit or implicit)
- Public interest (serious communicable disease)
List the criteria for disclosure
- Anonymous if practicable
- Consent
- Kept to a minimum
- Meets current guidance/la eg data protection
List the criteria for disclosure
- Anonymous if practicable
- Consent
- Kept to a minimum
- Meets current guidance/la eg data protection
List some of the millennium development goals
- Eradicate extreme poverty and hunger
- Achieve universal primary education
- Promote gender equality and empower women
- Reduce child mortality
- Improve maternal health
- Combat HIV/AIDS, malaria and other diseases
- Ensure environmental sustainability
What are the 2 key purposes of NHS press releases?
Reactive - defending NHS reputation and Proactive - improving and protecting population health
What are the main influences of asthma?
Environmental (pollens, infectious rents, pets) and occupational (flour, cleaning agents, wood dusts)
What are the 3 factors in defining a migrant?
Country of birth
Country of nationality
Duration of stay
What is selection bias in screening?
People who choose to participate in screening programmes may be diff than those who not
eg may be at higher risk - women with fam history of breast cancer are more likely to attend OR may be at lower risk - women in higher socioeconomic groups who have a lower risk are more likely to attend
Define lead time bias
When screening appears to increase survival time simply because the disease is detected earlier
(once this is taken into account may be little effectiveness of screening test)
Define probity
Means being and trustworthy, and acting with integrity
Why is routine health data collected?
- To monitor health of the population
- To generate hypotheses on causes of ill health
- To inform planning of services to meet health needs, including resource allocation
- To evaluate and assess performance of policies and services
List some types of health information
Deaths (mortality), diseases (morbidity), use/quality of healthcare etc
Define incidence (of a disease)
Number of NEW cases in a particular population during a particular time interval
= number of new cases/population at risk
Define prevalence (of a disease)
The TOTAL number of cases in a particular population at a particular point in time
= number of cases at a point in time/total population
Define error
Any preventable event that may cause or lead to patient harm
Adverse event and near misses are 2 outcomes of what?
A medical error
What is an adverse event?
Incident resulting in harm to a patient, which is not a direct result of their illness or other chance event
Human error contributes to many adverse events but not all adverse events result from human error
What is a near miss?
An event which arises during care and has the potential to cause harm but fails to develop further
What are the 2 ways in which errors can be described?
Errors of OMISSION (when required action is delayed or not taken)
Errors of COMMISSION (when wrong action is taken)
What are the 2 types of errors?
SKILL BASED - routine tasks given little attention. If distracted, may miss a step
KNOWLEDGE BASED - incorrect plan or course of action. More likely with complex tasks and inexperienced individuals
List some information processing limitations
Cognitive interference - more complex tasks make greater processing demands
Selective attention - limited attentional resources may lead to information overload
Cognitive biases - long term memory containing ‘mini theories’ rather than facts leave us liable to confirmation bias
What is a team?
- 2-12 people
- Team dynamics (feeling of belonging to the team)
- A common purpose/goal
- Identified team leader
Why is team working in healthcare important?
- Efficient service delivery
- May improve decision-making
- May reduce medical error
- Essential in modern healthcare bc of complex conditions/services/treatments
List a few environmental barriers to team-working
Different offices, shift working, location (ward based vs community), other commitments, part vs full time
What makes a good healthcare team?
- Clear roles/understanding of each member’s role
- Knowledge sharing
- Effective communication
- Shared goals
- Mutual respect
- Positive attitude
List some examples of common mental health disorders
Depression, generalised anxiety disorder, panic disorder, phobias
What is “sustained feelings of sadness interfering with ability to function at work/school/home, characterised by; loss of pleasure in doing things, decreased energy, feelings of guilt, disturbed sleep/appetite and poor concentration)”
Depression
2nd most commonly seen condition after hypertension in primary care
What is the social gradient in obesity?
Obesity shows a marked gradient by SOCIAL CLASS.
What are the cause of obesity?
Complex, multi-factorial and rooted in social, economic and cultural factors.
Factors include “americanisation” of diets, car culture, longer working hours, increased fast food, promotion of sugary drinks
What conditions does obesity impact?
Hypertension, CAD, stroke, type 2 diabetes, osteoarthritis, reproductive function
Define obesity
Abnormal or excessive fat accumulation resulting from chronic imbalance between energy intake and energy expenditure that presents a risk to health
Which BMI is classed as obese?
> 30kg/m^2
List some measures of obesity
Waist circumference, waste to hip ratio, BMI
What is Prader Willi Syndrome associated with?
Obesity
It is a congenital disorder characterised by short statue, intellectual impairment, mis-shaped hands/feet etc
Which factors influence obesity?
Lack of sleep, food preferences, reduced physical activity, cortisol/leptin/ghrelin
NB: cortisol (stress), leptin (appetite suppressant), ghrelin (increases hunger)
List some developmental factors ob obesity
Birth weight, rapid infant weight gain, breastfeeding (protective?), early introduction of solid foods
What is the difference between direct and indirect controls of meal size?
DIRECT: factors relating to direct contact of food to GI receptors
INDIRECT: everything else… metallic, endocrine, individual differences, social/env factors etc
Indirect controls have the ability to override direct controls
Define “what brings an eating episode to an end”
Satiation
What is the inter-meal period referred to as?
Satiety
What is energy density measured in?
kcal/g
What is the significance of energy density of food?
People tend to keep volume constant when consuming food.
Reductions in energy density are associated with reduced energy intake
List ways in which energy density of diets can be reduced
- Incorporating water
- Air
- Fruits/veg
- Reducing fat
- Cooking method
What is energy compensation?
The adjustment of energy intake following the ingestion of a particular food
Is energy compensation lower or higher with liquids than solids?
Lower
List a few of the key challenges of an ageing population (as according to WHO)
- Strains on pension and social security systems
- Increasing demand for health care
- Increasing demand for long-term care
List some causes of population ageing
- Improvements in sanitation, housing, medical interventions etc
- Life expectancy is rising world-wide
- Substantial falls in fertility
What are the 2 distinct types of ageing?
Intrinsic and extrinsic
What is intrinsic ageing?
Natural, universal and inevitable
What is extrinsic ageing?
Dependant on external factors eg UV ray exposure, smoking, air pollution etc
What are some physical changes associated with ageing?
- Loss of skin elasticity
- Loss of hair colouring
- Loss of joint flexibility
- Increased susceptibility to illness
- Less efficient memory
What is the gender bias in longevity?
Women live longer than men (5-8 yrs)
20% biological: until menopause, hormones protect women from heart disease
80% environmental: men take more lifestyle risks
List the 2 most common types of dementia
Alzheimer’s disease
Vascular dementia
What is the NHS committed to providing?
The best value for taxpayers’ money and the most effective, fair and sustainable use of finite resources
What is opportunity cost?
- To spend resources of 1 activity means a sacrifice in terms of a lost opportunity cost elsewhere
- The opportunity cost of an activity is the sacrifice in terms of the benefits forgone from not allocating resources to the next best activity
When is economic efficiency achieved?
When resources are allocated between activities in such a way as to maximise benefit
What is economic evaluation?
The assessment of efficiency
- Comparative study of the costs and benefits of health care interventions
How is health benefit measured?
- Natural units eg BP, pains core
- Quality Adjusted Life Year (QALY)
–> length (yrs) x quality (“utility”) [0-1 scale]
1 QALY = 1 year in perfect health or 2 years in half perfect health
List and briefly describe the 4 types of economic evaluation
- Cost-effective analysis (outcomes measured in natural units eg incremental cost per life year gained)
- Cost-utility analysis (outcomes measured in QALY eg incremental cost per QALY gained)
- Cost-benefit analysis
(outcomes measured in monetary units eg net monetary benefit) - Cost-minimsation analysis (outcomes measured in any units are the same in both treatments thus just cost is is minimised)
What is the incremental cost effectiveness ratio (ICER)?
Difference in costs / difference in benefits eg QALY
What is equity?
Equity is concerned with the fairness or justice of the distribution of costs and benefits
List some consequences of STIs
Infertility, mother-to-child transmission and chronic diseases
What are policy concerns and responses to STIs shaped by?
Not only patterns of disease and mortality but importantly social and political climate
When reporting risks, what should you always repot?
Length of time.
Eg risk of getting prostate cancer - is it the risk tomorrow or over a lifetime?
What is the equation for relative risk difference (RRD)?
(A-B)/B x 100%
eg if A = 0.6 and B = 0.2
RRD = 0.4/0/2 x 100% = 200% SO risk w/ drug A is increased by 200% compared to drug B
What is the number needed to treat (NNT)?
A measure that indicates the potential benefit of a clinical intervention to patients
What is the equation for NNT?
1/RD (risk difference)
where RD = R(drug A) - R(placebo)
NB: if RD is positive ie intervention is harmful rather than protective… NNH = 1/RD
What is the difference between descriptive and analytic studies?
Descriptive studies describe the occurrence of disease and generate hypotheses on disease aetiology WHEREAS analytic studies evaluate association btwn disease and exposure(s) and assess impact of interventions.
Analytic studies require a control group
What is the difference between experimental and observational studies?
Experimental involves planned intervention eg treatment allocation whereas observational studies involve no intervention in care, other than what is routine.
Experimental studies are always analytical whereas observational can be analytical or descriptive
How is an effect modification different to confounders?
Effect modification is an interaction that provides useful info eg if a new drug is tested, and it is found that age interacts (thus age is an effect modifier) WHEREAS confounders should be prevented or controlled
what is opportunity cost
sacrifice in terms of benefits lost from not allocating resources to the next best activity
when is economic efficiency achieved
when resources are allocated btwn activities in such a way as to maximise benefit
what is economic evaluation
the assessment of efficiency - comparative study of costs n benefits of health care interventions
analysed in terms of increments aka difference
how can health benefit be measured (3)
- natural units eg BP, pain q. score
- QALY
- monetary value
what is 1 QALY the same as (2)
1 year perfect health
2 years in half perfect health
