L20: Screening And Prevention

Question 1

What is screening

Answer 1

Investigation of people without symptoms to classify them as they are likely or unlikely to have the disease

Question 2

What happens to those who are screened and appear to likely have the disease

Answer 2

Investigated further

Question 3

What are the prerequisites of screening

Answer 3

Condition is important for public heath
There should be a treatment for the disease
Facilities for diagnosis and treatment should be available
There should be a pre-symptomatic and latent phase
Suitable test or examination
Test should be acceptable to the target population
History of disease should be understood
Agreed policy on who to treat
Cost effective
Programme

Question 4

What are the disease that are suitable for screening

Answer 4

Common and have severe consequences
Should have a pre-symptomatic phase but it is detectable
Early treatment must offer advantage
Screening needs to have a net benefit to patients

Question 5

What is lead time bias

Answer 5

Although someone who’s is screened and diagnosed before someone who hasn’t the time of death is the same they are only more aware of the condition for longer

Question 6

What is length time bias

Answer 6

Less aggressive/slow cancers are more likely to be detected with screening than aggressive disease because the disease will develop quicker

Question 7

What is sensitivity

Answer 7

The proportion of people WITH the condition who actually test positive

Question 8

What is specificity

Answer 8

The proportion of people WITHOUT the condition who actually test negative

Question 9

What is the positive predictive value

Answer 9

Proportion of people who have a positive test with the condition out of all the people that test positive

Question 10

What is the negative predictive value

Answer 10

The proportion of people with a negative test without the condition out of all the people that test negative

Question 11

For a good test what should the sensitivity and specificity be like

Answer 11

Maximised

Question 12

What are the 3 screening programmes currently in the U.K.

Answer 12

Breast cancer
Cervical cancer
Bowel cancer

Question 13

What screening method do we use to screen for breast cancer

Answer 13

Mammography

Question 14

Who is the breast screening programme targeted at

Answer 14

Women aged between 47 to 73 years old

Question 15

How often should women be screened for breast cancer

Answer 15

Every 3 years

Question 16

What are the disadvantages of breast screening programmes

Answer 16

• Lesions called ductal carcinoma in-situ can get picked up on a mammogram which do not metastasis
• This can lead to over diagnosis of breast cancer
• Over treatment

Question 17

What are the advantages of breast screening

Answer 17

reduced chance of dying

Question 18

What are the recommendations to increase people attending screening programmes

Answer 18

Text reminders
Social media campaigns
Links with community Groups
Increase awareness in transgender groups

Question 19

What is the most common cancer known in males

Answer 19

Prostate cancer

Question 20

What are the 3 potential tests for prostate cancer

Answer 20

Digital rectal examination
PSA test
Transrectal ultrasound

Question 21

What are the problems with the PSA test

Answer 21

• elevated levels doesn’t mean cancer as it can increase with sexual activity
• unreliable in different labs
• patient receives in appropriate treatment with sever side effects
• normal levels can still indicate prostate cancer