Which method is used to document TST results after administration?

Which method is used to document TST results after administration?

• A. Induration measured in millimeters.
• B. Erythema diameter measurement in centimeters.
• C. Visual inspection only, no measurement.
• D. Document only the site code.

Answer: (A)

Tuberculin skin test results are documented by measuring the induration—the raised, hardened area—in millimeters after 48–72 hours. Erythema (redness) alone isn’t used for interpretation, and relying on visual inspection without measurement misses the objective data needed to determine positivity. The induration size is measured across the widest part with a ruler or caliper and recorded in millimeters, providing a standardized basis for assessing exposure risk. Documenting only the site code or measuring erythema would not accurately reflect the immune response.

Tuberculin skin test results are documented by measuring the induration—the raised, hardened area—in millimeters after 48–72 hours. Erythema (redness) alone isn’t used for interpretation, and relying on visual inspection without measurement misses the objective data needed to determine positivity. The induration size is measured across the widest part with a ruler or caliper and recorded in millimeters, providing a standardized basis for assessing exposure risk. Documenting only the site code or measuring erythema would not accurately reflect the immune response.