The “within” timing operator allows testing if two data elements occur within a specific time range of each other. The within operator does not consider the order of the two events in time. Instead, the operator considers the absolute value of the difference in time between the start dates of the two events. While it is possible to express similar logic using existing operators, it requires multiple statements of logic to evaluate the time range before and after a given event to express the within construct. The following logical statements provide the within construct:

AND: 
    OR: X <= 30 day(s) starts before start of Y
    OR: X <= 30 day(s) starts after start of Y

This requires checking for relative events both before and after the target event. With the within operator this can be accomplished with a single statement:

AND: X within 30 day(s) of Y

Additionally, the within construct also provides significant value when negated. Using the within operator in a negated clause allows the logic to efficiently evaluate that data elements were not timed too closely to each other, and with specific occurrences it allows identifying occurrences that have an appropriate gap in timing between each other.