Calculate a simple observed survival proportion from survivor or death counts and a total cohort at the same follow-up point. Everyone’s outcome must be known; this tool does not handle censoring or estimate an individual’s prognosis.

Use whole-person counts from the same cohort at the same follow-up time, with everyone’s survival status known. This simple proportion does not handle censoring or predict an individual’s prognosis.

Survival Rate Formula

The following two example problems outline the steps and information needed to calculate the Survival Rate.

SVR = S / D × 100
  • Where SVR is the Survival Rate (%)
  • #S is the number of survivors 
  • #D is the number of people that contracted the disease 

For this simple observed proportion, divide survivors at a specified follow-up point by the original cohort size, then multiply by 100. The deaths mode assumes everyone else in that same cohort has died by that point. With unknown outcomes or unequal follow-up, use an appropriate survival-analysis method instead. This percentage is not a person-time mortality rate or relative survival.

How to Calculate Survival Rate?

The following example problems outline how to calculate Survival Rate.

Example Problem #1:

  1. First, determine the number of survivors.
    • The number of survivors is given as 500.
  2. Next, determine the number of people that contracted the disease.
    • The number of people that contracted the disease is provided as 2000.
  3. Finally, calculate the Survival Rate using the equation above: 

SVR = #S / #D * 100

The values provided above are inserted into the equation below and computed.

SVR = 500 / 2000 * 100 = 25.00 (%)

Example Problem #2: 

For this problem, the variables required are provided below:

number of survivors = 600

number of people that contracted the disease = 1800

Test your knowledge using the equation and check your answer with the calculator.

SVR = #S / #D * 100 = ?