# How Mental Health Conditions Are Assessed and Diagnosed

- Link: https://psychologyforeveryone.com/chapter/33-how-mental-health-conditions-are-assessed-and-diagnosed/
- Published: 2026-10-24T07:45:03+00:00
- Author: myadvisorfriend@gmail.com

> _A diagnosis is a map, not the territory: it shows where help may
>  lie, and it
> is never the whole of the person.

## 33.1 Why diagnosis matters

A good diagnosis can:

**IF YOU ARE WORRIED ABOUT A DIAGNOSIS**

A diagnosis can feel frightening. It is not a life sentence. If it
 brings thoughts
of harming yourself, tell someone today and contact your local emergency number 
or emergency service.

 * Give a name and an explanation for what has been happening, which is
    a relief
   for many people
 * Guide the choice of treatment
 * Allow communication between professionals
 * Provide access to services, support, and sometimes legal protection
    or workplace
   adjustments
 * Show what to expect over time

A diagnosis cannot capture everything about you. It is a tool for
 getting the right
help, not a definition of who you are.

## 33.2 Who can diagnose?

Depending on the country, mental health diagnoses can be made by
 psychiatrists,
clinical psychologists, trained family doctors, and some advanced practice nurses.
For complex cases, a team may be involved.

## 33.3 The diagnostic systems

Professionals use two major classification systems:

 * **ICD-11** (International Classification of Diseases,
    11th Revision), published
   by the World Health Organisation and used in most countries.
 * **DSM-5-TR** (Diagnostic and Statistical Manual of
    Mental Disorders), published
   by the American Psychiatric Association and widely used in research and in North
   America.

Both list conditions with symptom descriptions, duration, and the
 level of impact
on daily life. They aim to make diagnosis consistent from one professional to another.
They are updated as science develops, which is why some diagnoses have been renamed
or reorganised over the years.

## 33.4 The assessment⏎  process, step by step

### Step 1: The interview

The heart of any assessment is a conversation. The clinician will
 usually ask about:

![Figure 33.1 The steps of an assessment, from first meeting to a shared plan. (
Illustration created with AI tools.)](/wp-content/uploads/pfe-book/image56.webp)

**Figure 33.1** _The steps of an assessment, from
 first meeting to a shared plan.

 * **The current problem:** what you notice, when it
    started, how often, how severe,
   and what makes it better or worse
 * **Mood, anxiety, energy, sleep, and appetite**
 * **Thoughts:** worries, unusual experiences, thoughts of
    self-harm or suicide
 * **Behaviour and coping:** including alcohol, drugs, and
    medicines
 * **Daily functioning:** work, study, relationships,
    self-care
 * **Personal history:** childhood, schooling, major life
    events, losses, and any
   trauma
 * **Past mental health care** and what helped
 * **Family history** of mental illness
 * **Physical health** and medicines
 * **Current life situation:** home, money, support, and
    safety

You may be asked sensitive questions. Honest answers, even when
 difficult, help
the clinician help you.

### Step 2: The mental state⏎  examination

During the interview, the clinician also observes things such as
 appearance, speech,
mood, thinking, perception (for example, hearing voices), concentration, memory,
and insight into the problem. This structured observation gives a snapshot of how
you are at that time.

### Step 3:⏎  Standardised questionnaires and rating scales

Short questionnaires can help measure the severity of symptoms and
 track change
over time. Examples include scales for depression (such as the PHQ-9), anxiety (
such as the GAD-7), trauma, ADHD, and many others. They support a clinician’s judgement;
they do not replace it. Online quizzes that claim to diagnose you are not reliable.

### Step 4: Physical⏎  examination and tests

Because physical illness can mimic or cause mental symptoms,
 clinicians may order:

 * Blood tests (thyroid function, blood count, vitamin levels, blood
    sugar, liver
   and kidney function)
 * Checks for alcohol or drug use
 * Blood pressure, heart tests, and weight
 * Brain scans (CT or MRI) when there is a reason to suspect a physical
    brain problem,
   such as head injury, sudden personality change, or unusual symptoms
 * Sleep studies when sleep problems are prominent

### Step 5: Information from⏎  others

With your permission, relatives, teachers, or partners may give extra
 information.
For children and for conditions such as ADHD or dementia, this is especially valuable.

### Step 6: Psychological testing

A clinical psychologist or neuropsychologist may use specialised
 tests to assess:

 * **Intelligence and learning:** to understand strengths
    and learning difficulties
 * **Attention and memory**
 * **Personality**
 * **Autism and developmental assessments**
 * **Cognitive decline** in older adults

Testing is done in a quiet room and may take from an hour to several
 sessions.

### Step 7: Formulation and⏎  diagnosis

The clinician combines all the information into a
 **formulation**, a summary that
explains what is happening and why, based on biological, psychological, and social
factors. From this comes a diagnosis (or sometimes a “working diagnosis” that will
be reviewed), along with a plan.

## 33.5 The risk assessment

Every good assessment includes a check of safety. The professional
 may ask, directly
and kindly, about thoughts of suicide, self-harm, or harming others, and about protective
factors such as family, reasons for living, and future plans. This is routine and
not a sign they think you are “dangerous.” Honest answers allow the right support.

## 33.6 Common diagnostic⏎  challenges

### Overlap of symptoms

Many conditions share symptoms. For instance, poor concentration
 occurs in depression,
anxiety, ADHD, trauma, sleep deprivation, and thyroid disease. Clinicians must carefully
tease apart causes.

### Comorbidity

It is common to have more than one condition at once. Around half of
 people with
one anxiety or mood disorder also have another. A good plan addresses all of them.

### Changes over time

A diagnosis may be refined as new information appears or as the
 person’s situation
changes. For example, someone first diagnosed with depression may later show episodes
of mania, leading to a diagnosis of bipolar disorder.

### Culture and context

Ways of expressing distress differ across cultures. Some communities
 describe emotional
pain mainly through physical symptoms; others have culturally specific syndromes.
A skilled clinician considers language, beliefs, and cultural context, and uses 
interpreters when needed, so as to avoid misdiagnosis.

### Normal reactions versus⏎  disorders

Grief after a loss, sadness after a setback, or worry before a major
 event are 
normal. Diagnosis is not made merely because someone is upset. Professionals look
for severity, duration, and impact on life.

## 33.7 How accurate is diagnosis?

There is no blood test for most mental illnesses. Doctors agree well
 on some diagnoses,
such as autism or schizophrenia, and less well on others, such as anxiety or some
personality disorders. Asking for a second opinion is normal, especially if treatment
is not helping.

## 33.8 Understanding⏎  and living with a diagnosis

### Common reactions

People respond to a diagnosis in different ways:

 * **Relief:** “At last I know what is wrong.”
 * **Sadness or fear:** “Will I always be like this?”
 * **Denial:** “They must be wrong.”
 * **Shame or stigma:** “People will think less of me.”
 * **Hope:** “Now I can get the right help.”

All of these are normal. Give yourself time.

### Questions to ask your⏎  clinician

 1.  What is my diagnosis, and what does it mean in plain words?
 2.  What do you think caused it?
 3.  How certain are you, and could anything else be going on?
 4.  What are my treatment options, and what are the benefits and risks of
      each?
 5.  How long before I might notice improvement?
 6.  What can I do for myself?
 7.  How will we know if the treatment is working?
 8.  What should I do if things get worse?
 9.  How should I tell family, school, or my employer, if at all?
 10. What is the long-term outlook?

### Privacy and sharing

You decide who to tell. Many people find it helpful to share with a
 few trusted
people. In some countries, laws protect you against discrimination at work or school
and allow reasonable adjustments. Medical records are confidential and are shared
only with your permission or where the law requires.

## 33.9 Labels: helpful and⏎  harmful

Labels can be a source of understanding but also of stigma. Some
 people embrace
their diagnosis as part of their identity; others prefer not to. Either choice is
valid. A few points to remember:

 * You are **not** your diagnosis. You are a person who
    _has_ a condition.
 * Avoid using diagnoses as insults or jokes.
 * Do not diagnose friends or family members; leave it to
    professionals.
 * Avoid self-diagnosis from social media videos or online lists. Traits
    described
   are often common to everyone, and wrong labels can mislead people or delay proper
   care. At the same time, if something strikes you as familiar, it is entirely 
   reasonable to bring it to a professional for assessment.

## 33.10 Screening versus⏎  diagnosis

A **screening** tool is a short test that flags people
 who may need a full assessment.
Screening is not diagnosis. A high score means “talk to a professional,” not “you
have the condition.” Likewise, a low score does not guarantee you are well if you
are worried.

## 33.11 Assessment of⏎  children and young people

Children cannot always describe their feelings in words, so
 assessments include:

 * Interviews with parents or carers and the child
 * Information from school
 * Observation of play and behaviour
 * Developmental history from pregnancy and early years
 * Questionnaires for parents and teachers
 * Tests of learning, speech, or cognition when appropriate

Early assessment is valuable because earlier help brings better
 results. If you
suspect a problem, do not “wait and see” for too long.

## 33.12 Digital tools and apps

Apps, online screening, and teletherapy can improve access,
 especially where services
are limited. Use those from reputable health organisations, and remember that tools
support but do not replace a qualified professional, especially in crisis.

**TRY THIS: KEEP A SYMPTOM DIARY BEFORE YOU GO**

For one to two weeks before your appointment, write each evening:
 your mood (0 
to 10), hours slept, energy, appetite, main worries, any unusual experiences, alcohol
or other substances, medicines taken, and what happened that day. Bring the diary.
It gives your clinician a much clearer picture than memory alone.

## Reflection activity

 1. Think of a time you or someone close was given a label (a diagnosis,
     a nickname,
    a “type”). How did it help? How did it hurt?
 2. What three questions would you ask a clinician at a first
     assessment?
 3. Which people in your life could you tell about a diagnosis, and how
     would you 
    decide?

## Key points to remember

 * Diagnosis rests mainly on a careful interview and observation,
    supported by 
   questionnaires, physical checks, and sometimes psychological tests.
 * Doctors use agreed systems (ICD-11 and DSM-5-TR) so that diagnoses
    are consistent.
 * Physical illnesses can mimic mental health conditions, so medical
    checks matter.
 * You have the right to ask questions, seek a second opinion, and
    decide who to
   tell.
 * A diagnosis is a guide to help, not a definition of who you are.