Background

The Derived Parameters table (DRx table) is typically configured in a telemetry collection for 1-10 minute averages.  Although these averages can vary greatly, this is a common averaging interval for continuous collections.  Often times, varying lengths of intervals or specific time points in relation to a specific time point (e.g. time of dose/exposure) are desired.  Data Reduction provides a second method to reduce, or average data, over a user-defined interval to provide that additional flexibility. 

Data Reduction allows the user to generate a second table, per animal, that may be more indicative of averaging intervals that will be used for reporting.  There are multiple “Types” or methods for determining Data Reduction intervals.  These include Time, Data Lines, Variable and Parser.

• Time: allows the User to enter a specific averaging interval that will be repeated after the activation of an Event (T0). This is the same method that is used in the DRx table generation.
• Data Lines: refers to the logged lines of data in the DRx tables. If the logging rate is set to 10 seconds and six is the number of logged lines of data desired, the interval will report a total of 60 seconds of data. This interval will be repeated after the activation of an Event (T0). 
• Variable: allows the User to manually enter a list of times into the system. Unlike Time or Data Lines, Data Reduction will stop after the last manually entered time span has completed.
• Parser: allows the user to bracket data of interest. This can be in the form of a repeating, fixed interval or can be configured at user specified times and intervals.  This interval will be repeated after the activation of an Event (T0).

This tutorial will focus on creating Data Reduction intervals using Parser.

Configuring Data Reduction Using Parser

The Data Reduction dialog must be enabled in order to make modifications.  Select the check box next to “Enable” in order to edit the various fields.  If multiple animals/groups are being configured.  Use the Shift key to select multiple Groups.  When using the Shift key to select multiple Groups, any information configured for one group will automatically be populated for all other selected Groups.  Below shows Groups A-D selected for editing and a check next to Enable.

Control and T0 Events

When using Parser Segments for Data Reduction intervals, it is important to note that the Control period will be the first Parser Segment that is created in the data set.  Although the Duration edit field allows you to specify a time for your control period, once the Type is set to “Parser Seg” the time for the control is no longer relevant and will be controlled by your Data Parser Setup (not covered in this document).  If a control is desired, check the edit box next to “Control”.  This will then update the spreadsheet to utilize the first segment as the control period and will then expose additional parameters that are available for selection under “Calculations”.

Finally, the use of a separate event to initiate your control period and a separate event to initiate your data reduction going forward after an event (T0), does not apply with Parser Segments.  The first event that triggers Parser Segments to be created will create all segments.

Type and Auto Label

To utilize Parser Segments, select “Parser Seg” under the Type pull-down menu.  Once Data Reduction has been configured, Parser Rules should be constructed.  However, Parser Rules can also be created in Review.

“Auto Label” will allow the software to create labels automatically for each segment that is created.  This is recommended as the number of segments could be quite large and hand entering them would be a time consuming process. 

In the example above, “Minute {N}” is selected.  The term “Minute” is user defined and any descriptor can be entered here such as segment, interval, minute, etc.  The notation {N} will enter a value incrementing by 1 from your T0 event or the start of your Data Reduction intervals.  Entering {M} will show the actual time from T0.  This information will be shown in the spreadsheet under the label column (see below).

Finally, select the desired output under the “Calculations” field.  Again, if a Control period is specified, additional parameters will be available.

This is an example of a single Parser rule being applied to the dataset with consistent segment durations.  You will notice that the signals are bracketed and binned into 21 Data Reduction intervals.  However, multiple rules may be created and applied to the dataset and parser segments may or may be of equal time durations.  Creating Data Parser Rules is covered elsewhere.