In CMS 1017 eCQM (Hospital Harm - Falls with Injury), there is the following guidance - 

"Hospital days are measured in 24-hour periods starting from the time of arrival at the hospital (including time in the Emergency Department and or Observation).  The number of days will be counted as whole numbers; any fractional periods are dropped. For example, an eligible encounter with a length of stay of 75 hours will be measured as 3 days (72 hours)."

What if an encounter has a total hospitalization LOS of say 23 hours? In this case the Denominator observation would be 0 days. Say there is a fall with major injury during this time, then the numerator will be 1. But that poses a problem because now you are dividing 1 by 0 which is mathematically not possible. 

We might say that this encounter does not contribute any days to the denominator observation. But what if, unlikely in the real world but not impossible, all encounters with falls, have LOS less than 24 hours. Now when trying to calculate the aggregate rate across all encounters we will be dividing by 0 and that poses a problem. 

Could you help us figure out how to address this scenario?