When talking about treating mental health issues, it’s important to look at what medical staff, researchers, and people with mental health issues consider to be successful treatment. As its a lot harder to measure and accurately define mental health symptoms than physical ones, it is harder to accurately judge treating them. To show what kind of terms are used when treating mental health conditions, I’m  using some hypothetical case studies. Imagine that each of these patients has just been diagnosed as being in their first Major Depressive Episode, and this is their first mental health issue. Each patient starts with a score of 18 on the PHQ-9, representing moderately severe depression using that system, is treated with an antidepressant, and is followed up six months later.

Response

After a six-week course of medication, Patient A retakes the PHQ-9 and scores 14. Six months later, their score is 15. Because their score has stayed lower, Patient A has had a treatment response. Their diagnosis would not change. In a purely medical sense, this is progress. An academic study testing the effectiveness of patient A’s antidepressant would be happy with a 3-point response, and would consider this a successful response. However, the patient themselves won’t see it that way.

A score of 15 is still in the category of moderately severe depression. Their day-to-day feelings and experiences may not have changed in any meaningful way and, depending on what side-effects the medication had, they may not feel the treatment was worth having.

Recovery

Patient B, after the first course of treatment, scores 4 on the PHQ, and scores 4 again six months later. This is in the non-depressed range of scores, meaning they would be considered recovered. Medically, everyone would now assume that they were fine and that they would function at the same level as before experiencing depression. Their diagnosis would change to Major Depressive Disorder, in full remission. Recovery, defined as “a return to health or functioning”  is usually the ultimate goal of both patients and doctors.

Recovery is often equated, both in media and from people unfamiliar with mental health conditions, with being cured; a marker that this episode of difficulty is over and everything can return to normal, in the same way as with physical illnesses. Many mental health services and charities instead talk about “the recovery process”, defining a person’s recovery as them regaining control of their life and growth whatever their mental health symptoms.

The Grey Area: Partial Remission

Full remission means there are no remaining signs of the illness. This doesn’t mean it’s gone forever, just that it’s not here now.  Looking at its origin- the Latin word remissionem meaning “to relax, to send back”- makes this  clearer. However, we also need to look at partial remission. In the DSM-IV, partial remission means that a person doesn’t fully satisfy the diagnostic criteria of their illness but still has symptoms of it. The person may still be affected in their daily life by their illness, and may not be the same as they were before it. Their illness can either continue in partial remission,  lessen again into complete remission, or return.

Patient C, after their course of treatment, retakes the PHQ-9 and scores 9  (mild depression by the PHQ scoring system). They also score 9 on their next assessment, 6 months later. Patient D, after treatment, scores 4 on the PHQ  (meaning they are currently non-depressed). However, 6 months later their score is 10 (moderate depression). Patient C would usually be diagnosed as having Major Depressive Disorder, in partial remission. Partial remission is also used when a person has no symptoms, but has not yet reached the time limit for their illness to be “over” as defined by the DSM. In this case, where we’re looking at major depressive disorder, that time period is about two months.

Depending on how long they were without symptoms for,  and how much different they felt during treatment,  patient D has two diagnostic options. Patient D, and their doctor, could interpret their last few months as a temporary improvement; that they felt a bit better and then worse again. The doctor could classify them as still being in the same Major Depressive episode, but having been in partial remission after treatment.

However, patient D could have felt like they were completely fine for a few months, but then noticeably got worse. If so, it might be more sensible to classify this as a complete recovery from the first depressive episode, and a new separate episode starting. In this case, their diagnosis would change to Major Depressive Disorder, recurrent.

Patient D shows just how arbitrary diagnoses can be at times. Either diagnosis would work, in a factual sense, but which is correct depends on whether patient D could accurately explain what they felt, and how the doctor interpreted their explanation. In this case, there isn’t much difference in treatment between the two possible diagnoses, so even if one was more accurate than the other, it wouldn’t have a negative effect on patient D.

When it comes to people with multiple mental health issues, or long-term health conditions, however, the situation gets even more complicated.