Does the description refer to the condition or to the concern about the condition? It must be the latter or else I'd assume you'd simply utilize the existing condition data type. But if the latter, then when a concern status changes from active to inactive, all that can be inferred is that the patient stopped worrying about the condition, not that the condition itself had abated on its own or responded to medication. If the status is active, there's no way to know if the condition causing the concern is present or not. I might be concerned about a condition because of family history. So after all what would the recipient of this information really be able to do with it besides review each and every active concern with the patient to determine if the concern has become realized and wouldn't that be the same as starting from scratch and asking "So what are your concerns"?

This could be an extremely useful feature for patients who have memory problems or are otherwise unable to reliably relay their concerns to a physician.  It's not unusual for a patient with even mild dementia to get to a doctor's office and not be able to remember why they were there in the first place.  This could also be a great way for caretakers who are unable to attend doctor's appointments to make sure that their observations and concerns are communicated to the physician.  

Sure, I read a report about multivitamins being related to prostate cancer, jot down my concern. Three months later, long after I've forgotten about the report, I have my annual exam and my physician sees the concern and discusses the issue with me. Certainly valuable. In other cases though I maintain there is limited value and possible danger in listing concerns. If I've written down a concern about experiencing dizziness, should my physician merely assume that I'm experiencing dizziness? I would say no. A concern about a symptom is not the same thing as having the symptom. If I have the symptom, I should enter that using the condition data type along with a date of onset. Think about this in one of the cases you mention, I experience a bout of dizziness and my caretaker enters it using the concern datatype, during my exam my physician asks me about the entry and I can't remember having had the episode, what should my physician conclude? The issue has to do with the mess caused by conflating mental states about conditions with conditions themselves.