Required and optional steps
The importance attribute of a step is used to indicate whether an element is optional or mandatory.
The step and substep elements have an optional importance attribute, which has two valid values: optional and required. The attribute is used to indicate whether the step is optional (within a set of mandatory steps), or required (within a set of optional steps). The optional setting is more commonly used than required.
During processing to a reading format, steps with an
importance attribute are typically rendered with an
Optional:
or
Required:
prefix.
