The purpose of a smear test, also known as a Pap smear or Pap test, is to screen for cervical cancer, which is the second most common cancer in women today. Cervical cancer progresses through four stages: CIN1, CIN2, CIN3, early-stage cancer, and invasive cancer.

The objective of performing a smear test is to detect the patient in the first four stages. This is because treatment is much easier when detected at these stages.

If a patient already has obvious cancer, they may need to undergo major surgeries or receive radiotherapy.

The smear test involves taking a swab from the cervix using a special instrument. This swab is then examined to determine if there are any changes in the cells from the cervix that have the potential to develop into cancer and the degree of these changes. The classification is based on this assessment. The goal is to detect these cellular changes before they develop into cancer.

In terms of timing, it is generally recommended for women to start getting regular Pap smears at the age of 21 and continue every 3 years. However, the specific timing and frequency may vary based on individual health circumstances and a healthcare provider’s recommendations.