Question

Explain 1) mass screening and 2) selective screening, and compare them in terms of advantages and disadvantages. Give one example for each where mass or selective screening test is the most appropriate and explain your reasons.

Answer 1

Screening is a test or procedure that is done in a person or group to identify the disease or disorder that is unrecognized yet.

There are different types of screening - Mass screening, selective or high risk screening, Multiphasic screening tests.

MASS SCREENING:

Mass screening is a type of screening in which a large group of population are screened for a particular disease irrespective of their risk status to that disease.

ADVANTAGES:

• It decreases the mortality rate by identifying the disease at early stage thus improving the prognosis.
• It is useful for providing data to the epidemiological research.

DISADVANTAGES:

• It is not cost friendly due to large population.
• It is not used to prevent the disease.

EXAMPLE: TUBERCULOSIS- It is spread to one individual to another through droplets of saliva, so it is easily contracted between the individuals and also it is a silent type of disease which shows symptoms only in immunocompromised persons. So, by early detection of this disease can help them get the treatment at early phase. Also, we have a vaccine for T.B now.So the ones tested negative for T.B can be vaccinated thus decreasing the incidence of this disease.

SELECTIVE SCREENING:

Selective screening is a type in which only the individuals who carries risk to a particular disease are being tested.

ADVANTAGES:

It is cost effective when compared to mass screening due to limited number.

It reduces the complications of a disease by testing at early stage.

DISADVANTAGES:

It does not necessarily provide the treatment or alter the disease course.

It is more tedious as it have to find the high risk and low risk individuals prior to the screening tests.

EXAMPLE: HIV SCREENING TESTS IN HOMOSEXUAL MEN as the risk of contracting HIV is more in that group.So, by early detecting leads to initiation of the antiretroviral therapy and slow down the disease progression.