WebPT Ideas and Discovery

I want to know which current patient's DO NOT have future appointments. We have a way to look at past and future visits, and also lost patients but no report that tells me which active patients no longer have future patients within a specific date range. the only way I know to do it is to click on an individual patient and see if they have any upcoming visits. If they do, great, if they don't then I know to either schedule more visits for them or that it's their last visit with us so they may be a potential discharged patient.

I want a report to show my which patients, in total, per clinic, or per therapist, who DO NOT have any future appointments scheduled. Either for the day, or for a date range.