2 Replies Latest reply on Aug 28, 2018 7:46 AM by jonathan kassak

    Turnoover Time

    jonathan kassak

      I am attempting to review Radiology machine room turnover time by
      looking at (and sorting) by date, machine ID, begin exam time and end exam


      The formula below works most of time but there are several
      instances when I do not get “O” on the first row.


      Here’s the formula I am using:


      <0 Then 0




      Looking for an option or formula tweak that would always
      force a 0 in the first row.  There are some dates when a specific machine is used only one time in a given day and I don't know if that might be messing things up or not.


      Second question is more of how might you approach or deal
      with type of question.


      There are several dozen instances (in a population of about
      15000 Xray exams) when a subsequent “begin exam time” seems incorrectly entered
      by the user. That is, a “begin exam time” for a following case starts before the “end
      exam time” on the previous case.


      Given my formula (se above), this results in 0.

      For example:

      Date      Machine              Begin exam time              end exam time

      8/1/18   1                              13:35                     14:12

      8/1/18   1                              14:01                     14:15

      Has anyone had similar issues to this and, if yes, how have
      you dealt with this issue?  My population
      size is large enough that I don’t think I’d lose much by excluding such

      I am using version 10.5.


      1. Thank you in advance J
        • 1. Re: Turnoover Time
          Joe Oppelt

          this is one of those times when a sample workbook would really help me give you a good answer.


          Can you hack up an anonymized workbook so we can have something to work on together?


          Check out this link:


          Video demonstrates how to anonymize your workbook/data


          When I compare things to the prior row, I usually have a special part of the calc that forces what I want into that first instance.

          IF INDEX() = 1 then ...




          (all the rest of your stuff...)



          • 2. Re: Turnoover Time
            jonathan kassak

            Hi Joe and Tableau Community:


            Many thanks for reviewing and your helpful suggestion to include a workbook! It is attached.


            Ideally, I like to see the turnover time (end exam time to begin exam time) for a first case of the day, for a specific radiology machine, as always zero (0).


            Can you assist me with using an Index and the computation for that?


            Also, as you might see in some of the output, some subsequent cases for a machine on a given day have "begin exam" times that occur before the "end time" of a previous case (user input error, I guess).  This is presently resulting in 0 - not what I want.


            Any recommendations on how to best exclude instances when that happens or other workaround suggestions?


            Many thanks for any help and ideas.  I'm using 10.5