9) Population Based Screening Flashcards
What are the different way in which disease can be detected?
Spontaneous presentation
Opportunistic case finding
Screening
What is the purpose of screening?
Give a better outcome compared with finding something in usual way, due to intervening earlier
What is screening?
Systematic attempt to detect an unrecognised condition by tests, examination and/or other procedures
What is a diagnosis?
Identification of a suspected disease through tests, examination and/or other procedures
What are the criteria that need to be considered for a screening programme?
Condition Test Intervention Programme Implementation
In terms of the condition, what things need to be considered if there is to be a new screening programme?
Important health problem that is well understood
All cost effective primary prevention intervention implemented
In terms of the test, what things need to be considered if there is to be a new screening programme?
Simple, safe, precise and validated
Cut off levels defined, test values in pop. known
Acceptable
Agreed policy on further diagnostic investigation to those that test positive
In terms of the intervention provided, what things need to be considered if there is to be a new screening programme?
Evidence that intervention at pre-symptomatic phase leads to better outcomes
Agreed policies on which people and what intervention should be offered
In terms of the programme itself, what things need to be considered if there is to be a new screening programme?
Effectiveness in reducing mortality
Clinically, socially and ethically acceptable
Benefit gained should outweigh harms
In terms of the implementation, what things need to be considered if there is to be a new screening programme?
Patient outcomes optimised
All other options for managing condition considered
Informed choice to potential participants
Quality assurance
What is a false positive in screening?
Refer well people for further investigation
What are the implications of false positives?
Stress, inconvenience and costs
Lower uptake of screening In future
What is a false negative in screening?
Failure to refer those who have an early form of disease
What are the implications of false negatives?
Inappropriate reassurance and delayed presentation
What is sensitivity?
Detection rate, proportion of people with the disease that test positive (a/a+c)