ApexTrack Touchdown % parameter in Empower Software

<p>Hello-</p><p></p><p>The Empower software ApexTrack processing method Touchdown % parameter controls the placement of peak's baseline end times. The current default value for this parameter is 0.5%. This default value was chosen due to the fact that many peaks tail, and in such cases, a setting of 0.5% will prevent the peak end time from occurring too late. However, for peaks with less tailing, a Touchdown % of 0.5 may cause the peak end time to occur too early.</p><p></p><p>Waters would like to get your input as to whether or not you feel this default setting is appropriate or whether you would prefer that it is lowered, perhaps to a value of 0.05.</p><p></p><p>If implemented, this change would take place in a future version of Empower software and would not impact existing ApexTrack processing methods-the Touchdown % value would remain unchanged in existing methods. If this change were made, only new ApexTrack processing methods would use the new default Touchdown % value. Of course, this value can be set as desired, just as you can do in the current version of software.</p><p></p><p>When considering this, please think about what value would work best for the majority of your data, knowing that a single value will never be appropriate for all types of data. Also consider the impact to you if Waters were to make this change-would this affect any of your SOPs? Are you used to the current default setting and hence a change to this setting may represent a change in your workflow? Would a change have a positive, negative or neutral impact to you?</p><p>Your thoughts and feedback are very much appreciated. </p><p></p><p>Lauren Wood</p><p>Informatics Product Manager, Waters</p>


  • Lauren,

    In many cases we find that a setting in the range of 0.05-0.1 works better as a starting point than the default 0.5. This would be a welcome change.

    Thanks for asking,

    Kevin Kolodsick

    Consultant Chemist

    Analytical Sciences R&D

    Eli Lilly and Company

  • ElSee


    A survey amongst ourselves reached a consensus of 0.00. We usually start from there and work our way up.

    Tony Pecora

    Pfizer Consumer Healthcare

  • Hi Lauren,

    I always start with a touchdown percent of 0.1% and this seems to work pretty well for most of our methods so anything in the region of 0.05 - 0.1% would be a welcome change I think also.

  • I also start low and work my way up. If I have one particularly troublesome peak, I'll leave the %TD high and bump up the PW for the odd peak if it comes out too narrow w/ the PW used elsewhere.

  • Lauren,

    In our laboratory, we always start with a setting of 0.05 % and in many cases it is still too high.

    Damien Brunner

    BASF Pharma

  • As you are talking about future versions of Empower, could it be an option set during project initiation?  Maybe where you allow Apex tracking or not, also have a default value for touchdown and liftoff?  You should know about what to expect for existing methods.

  • tsryder

    I agree that it would be nice for each installation to be able to set their own default value, either in the System Policy/Data Processing Policies where you choose the default integration technique, or as part of the New Project wizard, or both.

    Also - thanks for soliciting input from the community!

  • We typically use values from 0.05 to 0.01.  Defaulting the value to 0.000 would be consistent with the % Liftoff default value.  I suggest defaulting it to 0.000.