If you've started looking into ADHD for yourself or your child, you've probably run into a lot of acronyms. ASRS. Vanderbilt. Conners. SNAP. CADDRA. A teacher may have sent home a form, or you may have taken a quick online screener and wondered what your score means. This guide explains what these rating scales are, who fills them in, what they can and can't tell you and where they fit in a full assessment.
This post is general information, not a diagnosis.
What an ADHD rating scale is
A rating scale is a structured questionnaire. It lists behaviours linked to ADHD, such as trouble staying focused, restlessness or acting before thinking, and asks how often each one happens. Answers are usually given on a scale, from "never" to "very often."
Rating scales are useful because they:
gather information in a consistent way
compare answers with what's typical for a person's age
collect views from more than one setting, like home and school
help track changes over time
But a rating scale on its own is not a diagnosis. It's one piece of information, and a careful clinician puts it together with many others.
Screening vs diagnosis
It helps to know the difference:
Screening tools are short questionnaires that flag whether ADHD might be worth looking into. A high score means "check further," not "you have ADHD."
Diagnostic assessment is a full process led by a qualified clinician. It looks at history, current challenges, other possible explanations and how symptoms affect daily life.
In Ontario, psychologists and nurse practitioners can diagnose ADHD. Our Registered Psychotherapists and Registered Social Workers provide counselling, not diagnosis.
The ASRS, for adults
The Adult ADHD Self-Report Scale (ASRS v1.1) was developed with the World Health Organization and the Workgroup on Adult ADHD. It includes a short screener of six questions and a longer checklist of eighteen.
Because the screener is free and quick, it's one of the most widely shared tools online. That's why many people first meet it as an "ASRS ADHD test." It can be a helpful starting point. Still, it only asks about current symptoms, and those symptoms can also come from anxiety, depression, poor sleep, stress or other conditions.
The Vanderbilt, for children
The NICHQ Vanderbilt Assessment Scales are used by health care professionals to help assess ADHD in children aged 6 to 12. There are separate forms for parents and teachers, so the clinician can see how a child is doing at home and at school.
A Vanderbilt ADHD assessment form also asks about other concerns, such as mood, anxiety and behaviour, and about how a child is doing with schoolwork and relationships. If you've been handed a Vanderbilt questionnaire, answer as honestly as you can, based on what you actually see, rather than what you think the "right" answer is.
The Conners, for children and teens
The Conners rating scales are a family of questionnaires sold by MHS for use by qualified professionals. The current Conners 4 covers ages 6 to 18, with parent and teacher forms for ages 6 to 18 and a self-report form for ages 8 to 18. There's a separate adult version.
If your child's school or a clinician gives you an ADHD Conners questionnaire, it's likely part of a broader assessment. Because it's a professional tool, scoring and interpretation are done by the clinician.
SNAP-IV and CADDRA forms
The SNAP-IV, named after its authors Swanson, Nolan and Pelham, is a parent and teacher rating scale for children. A SNAP ADHD assessment form is often used alongside other tools.
CADDRA, the Canadian ADHD Resource Alliance, publishes a toolkit of forms used by Canadian clinicians. It includes the ASRS, a version of the SNAP-IV and other questionnaires, along with an assessment form that walks through a person's history. When people talk about a "CADDRA ADHD assessment," they usually mean an evaluation that draws on this toolkit.
Interviews like the DIVA-5
Rating scales are often paired with a structured interview. One example is the DIVA-5, a semi-structured diagnostic interview for adults based on the DSM-5. It asks about symptoms in both adulthood and childhood, and about how they've affected daily life over time. There's also a version for younger people.
Interviews matter because ADHD is a lifelong condition. A clinician needs to understand your history, not just how you feel this month.
Tips for filling in a rating scale
If you've been asked to complete a questionnaire, for yourself or someone else, a few tips can make the answers more useful:
Think about a typical week. Try not to base your answers on one very good or very bad day.
Answer what you see. Describe how often something actually happens, not what you think should happen.
Don't overthink it. Your first honest answer is usually the most accurate.
Note the context. If something only happens in certain settings, like during homework or long meetings, mention it to the clinician.
Share other factors. Changes like a move, a loss, poor sleep or a new school can affect behaviour. The clinician will want to know.
Different people often rate the same person differently. A parent and a teacher may see very different sides of a child. That isn't a problem. It's useful information.
What rating scales can and cannot tell you
They can:
show whether ADHD-type behaviours are more frequent than typical for someone's age
highlight differences between settings, like home versus school or work
point to other concerns worth exploring
give a baseline to compare against later
They can't:
diagnose ADHD on their own
rule out other explanations, like anxiety, trauma, learning differences or sleep problems
capture the full picture of strengths and struggles
tell you what support will help most
That's why a score from an online screener isn't the end of the story. If it raised questions, the next step is a conversation with a qualified clinician.
Where scales fit in a full assessment
At our clinic, assessments for ADHD are led by a registered psychologist. Our adult ADHD psychological assessments in Kitchener-Waterloo use standard ADHD rating scales and questionnaires, along with a clinical interview, possible cognitive testing and a written report. Our Cambridge adult ADHD page explains the process there.
Which questionnaires are used depends on your age, your history and your questions. The psychologist chooses the tools that fit.
Assessments for children
If you're wondering about your child, our assessments start at age 6. Parents and teachers are often asked to fill in forms, since how a child acts can differ a lot between home and school. Mention your child's age in your free consultation so our admin team can guide you.
Offices and online options
We offer assessments and counselling in Waterloo, Kitchener, Cambridge and Ottawa. Our assessment pages describe them as in-person and/or virtual where appropriate, so ask about this when you book.
Counselling costs and billing
Assessment costs depend on what's involved, so ask our admin team during your consultation. For counselling before or after an assessment:
Individual sessions with our therapists range from $130 to $200, depending on the clinician.
Depending on your plan, insurance may cover some or all of the cost. Coverage varies, so it's worth checking your plan.
We accept Health Spending Accounts (HSAs).
We can direct bill many insurers, including for sessions with a Registered Psychotherapist (Qualifying). Desjardins is the exception: through TELUS eClaims, we can direct bill Desjardins for sessions with an RSW, RP or psychologist, but not for an RP (Qualifying).
Your first step
Book a free 15-minute consultation with our admin team. Let them know whether the questions are about you or your child, and which office or format you'd prefer.
If you're in crisis: call 911 if you're in immediate danger. If you're having thoughts of suicide, call or text 9-8-8 any time, day or night. You can find more options on our crisis lines page.
A score is just a starting point. Clear answers come from a full picture.