Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HaDSoc > Screening > Flashcards

Screening Flashcards

1
Q

Define screening

A

Systematic attempt to detect an unrecognised condition by the application of tests, examinations, or other procedures, which can be applied rapidly (and cheaply) to distinguish between apparently well persons who probably have a disease (or its precursor) and those who probably do not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How are diseases detected?

A

Spontaneous presentation
Opportunistic case finding (finding pathology whilst looking for something else)
Screening

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What disease/condition criteria must there be for implementing a screening programme?

A

Disease must be an important health problem
Epidemiology & natural history must be well understood
Must have an early detectable stage
Cost-effective primary prevention interventions must have been considered & where possible implemented

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What test criteria must there be for implementing a screening programme?

A

Simple & safe
Precise & valid
Acceptable to the population
Distribution of test values in the population must be known (proportion who test +ve & -ve)
An agreed cut-off level must be defined (who is counted as being test +ve)
There must be an agreed policy on whom to investigate further

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What treatment criteria must there be for implementing a screening programme?

A

Effective evidence based treatment must be available
Early treatment must be advantageous, not just bring forward the date of diagnosis
Agreed policy on whom to treat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What programme criteria must there be for implementing a screening programme?

A

Other options considered e.g. improving treatment
Benefit should outweigh physical & psychological harm
Facilities for diagnosis & treatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are false positives?

A

Screening programme refers well people for further investigation
Offered (invasive) diagnostic testing for a condition they do not actually have
Turned into “patients” when they are not actually

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are false negatives?

A

Failure to refer people who do actually have early disease

False reassurance for patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What factors are used to determine test validity?

A

Sensitivity (detection rate)
Specificity
Positive predictive value (PPV)
Negative predictive value (NPV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is sensitivity (Detection rate)?

A

The proportion of people with the disease who are test positive
The probability a case will test positive
“If I have the disease, will I test positive?”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is specificity?

A

The proportion of the people without the disease who are test negative
The probability a non-case will test negative
“If I don’t have the disease, will I test negative?”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a Positive Predictive Value (PPV)?

A

The probability that someone who has tested positive actually has the disease
PPV is strongly influenced by the prevalence of the disease - a high prevalence condition will have a higher PPV than a low prevalence one
- Only screen in high prevalence conditions
“If I test +ve, does it mean I definitely have the disease?”
Sensitivity & Specificity of a test can be the same, even if they have different PPVs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a Negative Predictive Value (NPV)?

A

Proportion of the people who are test negative who actually do not have the disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is sensitivity worked out?

A

True positives + False negatives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is specificity worked out?

A

False positives + True negatives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is PPV worked out?

A

True positives + False positives

17
Q

How is NPV worked out?

A

False negatives + True negatives

18
Q

What are the advantages of screening?

A

Early detection of disease may improve outcome

True negatives reassure patients

19
Q

What are the disadvantages of screening?

A

False positives expose patients to invasive diagnostic tests
False negatives falsely reassure patients
False negatives not offered diagnostic testing they may benefit from
Expensive interventions that divert money away from treatments

20
Q

What is lead time bias?

A

screened patients appear to survive longer, but only because they were diagnosed earlier
Patients live the same length of time, but longer knowing they have the disease
May impact upon patient’s quality of life

21
Q

What is length time bias?

A

Screening programmes are better at picking up slow-growing, unthreatening cases than aggressive, fast-growing ones
Diseases that are detectable through screening are more likely to have favourable prognosis & may indeed never have caused a problem
- Curing people that don’t need curing?

22
Q

What is selection bias?

A

Those who have regular screening are also likely to engage in other health behaviours that protect them from disease
Similar to ‘healthy worker’ bias
A RCT would help deal with this bias

23
Q

How may screening affect doctor-patient contact?

A

Normally sick person > doctor

Screenind doctor > Healthy (?) person

24
Q

What are the complexities of some screening programmes?

A

E.g. Cervical cancer
Which women do you screen?
How many abnormalities that are detected would regress spontaneously?
Incorporation of HPV testing

25
Q

What are the limitations of screening?

A

Screening carries potential for harm as well as benefit

For every life saved due to breast screening, about 3 women are investigated & treated unnecessarily

26
Q

Give examples of screening programmes in the UK

A 
Abdominal Aortic Aneurysm (AAA)
Bowel cancer
Breast cancer
Cervical cancer
Diabetic retinopathy
Down's syndrome
Foetal abnormalitie
PKU
Sickle cell & thalassaemia
27
Q

What 4 sociological critiques of health promotion & screening are there?

A

Structural critiques
Surveillance critiques
Social constructionist
Feminist critique

28
Q

What are structural critiques of health promotion & screening?

A

Victim blaming
- Individuals are encouraged to take responsibility for their own health
- Are all equally able to do this?
Individualising pathology
- What about addressing underlying material cause of disease?

29
Q

What are surveillance critiques of health promotion & screening?

A

Individuals & populations increasingly subject to surveillance
Prevention part of wider apparatus of social control?

30
Q

What are social constructionist critiques of health promotion & screening?

A

Health & illness practices can be seen as moral - given meaning through particular social relationships

31
Q

What are feminist critiques of health promotion & screening?

A

Is screening targeted more at women than men?

HaDSoc (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions