Why “First-Case On Time Percentage” Is Not An Ideal Metric

A few months ago, I was discussing OR metrics with a prospective client, an anesthesiologist.  “Of course, I know that working hard to reduce the first-case, on-time percentage doesn’t make sense,” he observed.  “We’ve known that for some time.”  Unfortunately, he’s in the minority.  Many still behave as though it’s one of the most important metrics to improve.

Here’s why it’s not.

Let’s start with the perspective of a patient who is lucky enough to be the first case of the day.  Although it would be great to be wheeled into the OR right on schedule, being 10 to 15 minutes late would not be too disturbing – “par for the course” when it comes to interactions with medical profession.  I grant you that I would be unhappy if I were delayed for an hour, particularly if I was in for a minor, outpatient procedure.  But we’ll come to that.

Now let’s look at it from the perspective of the perioperative system.  If the first patient is 15 minutes late, will the last patient be 15 minutes late emerging from the OR?  We don’t know.  It could be less or it could be more.   Suppose however, that our first cases start on the average 15 minutes late, then all other things being equal, they might end 15 minutes late.  Now, suppose we were able to improve our starts so that, on the average, we ended 5 minutes late.  How much would that be worth?  The right answer is “almost nothing” because it would be difficult to find something of value to do with that time.

Notice that in all the discussion we haven’t invoked “first-case on-time percentage.”  Why?  Because percentages don’t translate into value.  But time does.  That means that, at a minimum, we should add “minutes late” or “minutes tardy” to our set of operational metrics because it would give us a better understanding for how well – or badly – we’re doing.

“Now wait,” you might say. “You’re playing fast and loose with the end of the day.  Why shouldn’t we strive to end on time?”  To that, my response is that if that’s your goal, you’re much better off investing your energies into reducing Turnover Time.  Why?  Because you get more shots at it, and because some of the factors that contribute to getting a late start in the morning also contribute to long turnovers.  Think about missing instruments, missing consents, slow response from a lab, a patient who failed to turn up.  So, if you reduce Turnover Time, you’ll have a bigger effect on the end of the day.  And you may even generate a bonus: If your ORs perform a lot of short cases, you may be able to reduce Turnover Time enough to schedule an additional short case routinely.  This case would be in addition to the add-on that you’d generally want to perform.

Perhaps you’re still not satisfied.  “But what about discipline?  Don’t we want to set the right tone?”  Here, I would have to concede a point.  If your Turnover Times are already very short, then it’s likely that it’s one or more surgeons or anesthesiologists who are always turning up late in the morning.  If that’s the case, it will be up to the chiefs to deal with them.  It will not require a full-blown improvement program.

There’s a bigger issue here, however.  Perioperative leaders are constantly under pressure to improve performance.  Given their limited resources, they must choose their improvement project wisely.  Allocating scarce resources to improve first-case, on-time start percentages is not a good choice.