Age grading, or performance scaling, is a way of allowing participants of different ages, gender, and possibly other attributes to compare their performances as if they were all the same age and gender. An age-graded, or “relative,” performance is an actual performance compared to a standard.

An example will help. Suppose a 54-year-old female finishes a race in 49 minutes and 15 seconds, and a 33-year-old female finishes the same race in 47 minutes. The 33-year-old had the better performance. In addition to this absolute result (47 minutes is better than 49:15), we can compare how well the two participants performed relative to their ages. Generally, an older participant might be expected to require more time to finish the race than a younger one.

Continuing the above example, here are the age-graded performances of the two participants:

^* These standard times are made up to keep the example straightforward.

The standard time is the best time that a participant of a specific age and gender is expected to be able achieve. The grade is then the actual time divided by the standard. For the 33-year-old, this is 47:00 divided by 39:30 giving 1.19, approximately. Using the same division technique, the 54-year-old’s grade is approximately 1.07.

What do these grades tell us? The 54-year-old did better against the standard than did the 33-year-old. All else being equal, the 54-year-old had a better performance, not in absolute terms but relative to expectations. Age grading levels the playing field, so to speak. Here the 54-year-old can argue, and brag, that she is in better shape than the 33-year-old.

A grade of 1 means that a participant’s performance matched the standard. Less than 1 indicates a performance better than a standard, and more than 1 means a performance not as good as a standard. Also, we say that a grade of 1.07, for example, means that the performance was 7% from the standard.

In a later blog, we will delve into age grading more. We will show how grades are turned into times. This might allow an easier interpretation than just looking at grades. Also, it is important to understand that age grading is not an exact science. The key lies in developing the standards. This can be subjective and care should be taken to fully explain how they are determined.