Advanced DeepSee Modeling Guide
Defining Quality Measures
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This chapter describes how to define quality measures, which are similar to calculated measures (see Defining DeepSee Models). It discusses the following topics:

For a comparison of quality measures with more basic DeepSee model elements, see the chapter Summary of Model Options in Defining DeepSee Models.
Overview of Quality Measures
A quality measure is similar to a calculated measure that can be reused in multiple contexts. A quality measure is defined by a formula that combines MDX expressions. You specify the subject area or subject areas in which it is available, and you can control whether the quality measure is published (and thus available in the Analyzer).
Each quality measure is a Caché class definition, specifically a subclass of %DeepSee.QualityMeasure.QualityMeasure.
You can define quality measures either in the Quality Measure Manager or in Studio. This chapter discusses the Quality Measure Manager.
You can use quality measures as follows:
Introduction to the Quality Measure Manager
The Quality Measure Manager displays all compiled quality measure classes in the given namespace. You can use it to create, modify, and delete them. To access the Quality Measure Manager:
  1. In the Management Portal, select DeepSee.
  2. This displays the [Caché] > [Quality Measure Manager] page.
Here you can do the following:
Creating a Quality Measure
To create a quality measure:
  1. Select New.
    DeepSee displays a dialog box.
  2. Specify the following values, which are all required:
  3. Select OK.
    DeepSee closes the dialog box, and the middle area of the page now displays the initial definition of the quality measure, as follows:
    Every quality measure is expressed as a formula as shown here in the Measure field. In this case, the formula is:
    [Numerator]/[Denominator]
    Where Numerator and Denominator are the names of groups defined in this quality measure.
    Each group consists of one or more items, each of which is defined by an MDX expression.
    In the initial definition of a quality measure, each of these groups is defined as a constant (100). The initial value of this quality measure is 1.
    The bottom area of the page displays any additional information:
  4. Select Edit.
    Now you can modify the formula and make other changes. See the following sections.
  5. When you are done, select either Save to save the definition or select Save As to save it with a new name.
    When you save the definition, DeepSee automatically compiles the class and writes the quality measure definition into a system global.
Specifying the Expression for a Quality Measure
Except for linked quality measures, when you display a quality measure in edit mode, you can edit the overall expression, which looks like this initially:
Here you can do the following:
Allowed MDX Expressions
For MDX Expression, specify one of the following kinds of expressions:
MDX Expression cannot be a set expression. You can, however, use %OR to enclose a set and return it as a single member.
Search expressions are not supported within quality measures.
For information on creating MDX expressions, see Using MDX with DeepSee and the DeepSee MDX Reference.
How Groups and Elements Are Combined
The formula for the quality measure (shown below the Measure heading) determines how the groups are combined.
Within any given group, the elements are combined as an MDX set (that is, they are combined via logical OR). If you need to combine elements via logical AND, create one element that has an MDX tuple expression that combines the desired pieces. For example: ([patgrp].[h1].[medicaid].[yes],[age].[h1].[0 to 2])
To compute the value for a quality measure in any given context, DeepSee does the following:
  1. For each group, creates an MDX set expression that combines the elements in that group.
  2. Evaluates each group and determines its value.
  3. Combines the group values as given in the formula.
Note that a quality measure can define groups that are not used by the formula. This can be useful if you are using the special [%QualityMeasure] dimension to refer to groups, as described earlier in this chapter.
Editing Other Information for a Quality Measure
When you display a quality measure in edit mode, you can also edit Caption (at the top of the page), as well as the following area at the bottom of the page:
Here you can do the following:
The editable items here are as follows:
Defining a Linked Quality Measure (Quality Measure Alias)
A linked quality measure is an alias for another quality measure (the master measure). The master measure may or may not be published, and can belong to a different subject area.
To define a linked quality measure:
  1. Select New.
    DeepSee displays a dialog box.
  2. Specify the following values, which are all required:
  3. Select OK.
    DeepSee closes the dialog box, and the middle area of the page now displays the initial definition of the quality measure.
  4. Select Edit.
  5. For Linked To, select the parent measure and select OK.
    If you specify Linked To for an existing quality measure, the editor discards values for any optional properties of the measure.
  6. Optionally specify the following options:
    Other options are inherited from the master measure.
  7. When you are done, select either Save to save the definition or select Save As to save it with a new name.
    When you save the definition, DeepSee automatically compiles the class and writes the quality measure definition into a system global.
Checking the Expression for a Quality Measure
You might want to check the overall expression that defines a quality measure, particularly if the definition is complex. To do so, use the %GetExpression instance method of the quality measure. For example:
SAMPLES>set qm=##class(QM.Preventive.Child.QM7).%New()
 
SAMPLES>w qm.%GetExpression()
[tests].[h1].[leadscr].[yes]/([patgrp].[h1].[medicaid].[yes],[age].[h1].[0 to 2])
This is the expression for the following quality measure:
Deleting a Quality Measure
To delete a quality measure:
  1. Display its definition.
  2. Select Remove.
  3. Select OK.