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As an example, the 5th dose of DTaP is recommended at 4-6 years, as circled in red below. That is, for a typical child, the recommended due date for dose 5 of DTaP is the date of the child's 4th birthday. The overdue date would be the date of the child's 7th birthday. 
Clinicians may or may not be interested in overdue date. The overdue date might be useful in cases where the clinician may not prefer to administer a particular vaccine today, knows the child is returning for a future appointment, and is trying to decide whether to wait or not.Another way in which the overdue date could be used is with software that presents could be used to present an alert that a vaccine recommendation is already overdue. For In an EHR, for example, an EHR the display might highlight a forecast or use in red text if today's date is on or after the overdue date.
Note that As noted above, the general advice is to always give all vaccines that are recommended administer a vaccine as soon as possible , and to not waitonce it is recommended. For this reason, not everyone may wish to use the Overdue Date feature.
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