The Institute of Applied Psychophysiology — the world's first clinical body dedicated to the permanent biological resolution of anxiety disorders. Not management. Resolution.
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The Institute of Applied PsychophysiologyDigital Tools

Our Apps.

Clinical-grade digital products developed by the Institute of Applied Psychophysiology — built on 30 years of anxiety research and 650,000+ resolved cases worldwide.

ANXAPP

ANXAPP

by the Institute of Applied Psychophysiology

The anxiety test for GPs, therapists — and people just like you.

World First

ANXAPP includes the detection of predisposition to suffering from an anxiety condition — the first and only diagnostic of its kind worldwide.

65 validated questions. Clear, personalised results in under 5 minutes. Free, private, and no account needed. Developed over 30 years by the Institute of Applied Psychophysiology and used by individuals, clinicians, and healthcare organisations globally.

100% confidentialEvidence-basedFree to completeInstant resultsSuitable for all ages
Visit ANXAPP
ANXAPP — free anxiety test interface

650,000+

Helped globally

30 years

Of practice & research

42

Countries reached

15

Conditions covered

65

Validated questions

How It Works

Three steps. Under ten minutes.

01

Answer 65 questions

Across five key areas of anxiety experience. Takes 5–10 minutes. Answer honestly — there are no right or wrong responses.

02

Receive your personalised results

Scored using an evidence-based system developed across 30 years of anxiety recovery practice. Results delivered to your email instantly.

03

Get a clear path forward

Your personalised report explains your results and recommends the most appropriate next steps — whether that is reassurance, education, or direct recovery support.

Conditions Covered

Across the full anxiety spectrum

ANXAPP covers 15 distinct anxiety conditions — developed through 30 years of direct practice with over 650,000 people.

Panic DisorderGeneralised Anxiety Disorder (GAD)OCD & Intrusive ThoughtsPure-O — HOCD, POCD, ROCDPostnatal AnxietyEmetophobiaAgoraphobia & MonophobiaDerealisation & DepersonalisationEating DisordersSelf-Harming BehavioursSocial AnxietyChronic HypervigilanceFear of Losing ControlLow MoodHealth Anxiety

Who It's For

Designed for everyone.

Anyone who feels anxious but is unsure how serious it is

The test provides a clear, objective picture — no GP referral required.

People told 'it's just stress'

Who sense something more significant is present and want clarity before seeking help.

Those wanting to prepare before seeing a GP or therapist

A structured self-assessment to bring to a clinical appointment.

Healthcare professionals

Used as a structured intake or baseline measure for patients presenting with anxiety symptoms.

Frequently Asked

Common questions

Free · Private · Instant

Understand your anxiety in under ten minutes.

No account. No payment. No referral. Just 65 validated questions and a clear, personalised result — developed by the Institute of Applied Psychophysiology.

Start Free Test

No account required · Results in under 5 minutes · Secure & private

1,000s of Testimonials — Proof That Linden Recovery & TRT™ Therapy Delivers Permanent Recovery
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"I bought the method about 18 months ago. Right now I feel free of anxiety and panic attacks. Thank you."

Elizabeth P.

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Caz P.

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Mark T.

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Sarah W.

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David H.

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Angela M.

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Louise B.

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James F.

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"Linden Recovery & TRT™ Therapy is the only anxiety treatment that actually addresses the cause rather than the symptoms. Everything else I tried just masked …"

Karen S.

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Michael O.

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Patricia G.

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Susan T., RN

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Claire R.

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"I had panic disorder so severe I couldn't drive. After Linden Recovery & TRT™ Therapy I drove to Scotland from London — alone. That's the power of this program."

Tony W.

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Fiona K.

"I cried when I read the testimonials on Linden Recovery & TRT™ Therapy website because I thought — finally, someone who understands. Charles Linden understan…"

Rachel H.

"My anxiety had become so bad I'd stopped eating properly, stopped seeing friends, and barely left my room. Linden Recovery & TRT™ Therapy brought me back to …"

Emily S.

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Graham L.

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Nicola P.

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Dan K.

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Dr. Jane M.

"Every penny spent on Linden Recovery & TRT™ Therapy was worth it. I've spent tens of thousands on therapy over 10 years with no lasting result. Linden Recove…"

Peter C.

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Tracey L.

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Testimonial

"If you doubt this method works, check out further evidence in books such as 'rewire the brain' by John B Arden. It worked for me, and will for anyone if they…"

Hayley S.

Testimonial
Testimonial

"Just a note to anyone thinking of buying this product — It does work! I had all the symptoms including chronic muscle pain, racing heart, horrid thoughts, OC…"

Robert K.

Testimonial
Testimonial

"I just wanted to thank you personally, Charles, for your method! After only 5 weeks I have my life back. I never thought I'd feel OK again — I thought my lif…"

Gill H.

Testimonial
Testimonial

"I owe my life to Charles Linden. He was like an angel that came into my life and made me believe that I can get rid of my anxiety. I love this man with all m…"

Rey

Testimonial
Testimonial

"Just wanna say a quick thanks... You've made sense of it all now and I'm working with your pack every day. Worth every penny. The world's a better place with…"

Richard S.

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Testimonial

"I found the program during a time of suffering from acute anxiety and panic attacks. Not a single panic attack since, and that was 4 years ago. I know I'll n…"

Julie G.

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Testimonial

"God Bless you, for you already have changed my life over 5 years ago! I know your method works because I'm set free by it! You are a gift from God and I than…"

Bill S.

Testimonial
Testimonial

"I found your website by chance and I can believe it — I've read only the first 12 pages and for me it's enough! You can believe or not, but the change was im…"

Dr. Branko M., MD, MS — Serbia

Testimonial
Testimonial

"Charles Linden is doing things in the anxiety recovery field that no one else has even tried to do. For years I thought I was going mad, now I'm anxiety free…"

Rob K.

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Testimonial

"Recovery is real. It actually happens. I didn't believe it was possible. Then I did Linden Recovery & TRT™ Therapy. I am now anxiety free and have been for o…"

Kezia B.

Testimonial
Testimonial

"Linden Recovery & TRT™ Therapy has made me more self-confident, less anxious, and a much more compassionate person. I have been doing it for a year now and h…"

Isabelle R.

Testimonial
Testimonial

"You have a great gift from God in helping people my friend, keep up the good work! To all who may be curious or skeptical — it really does work! Stick with t…"

Brad H.

Testimonial
Testimonial

"It's amazing how much more relaxed I feel. I'm actually looking forward to life's big changes rather than frightened! I'm so thankful I came across Linden Re…"

Jennifer M.

Testimonial
Testimonial

"I had agoraphobia for 6 years and changed over 20 psychologists and psychiatrists but they couldn't help. After 6 years, I'm OUT again, feel so good, like no…"

Danejla K.

Testimonial
Testimonial

"This method works! Don't bother with all the other therapies out there that promise to work and cost a fortune. Mr Linden, you rock! I wish I had found the m…"

Lisa K.

Testimonial
Testimonial

"I bought the method about 18 months ago. Right now I feel free of anxiety and panic attacks. Thank you."

Elizabeth P.

Testimonial
Testimonial

"I've been doing Linden Recovery & TRT™ Therapy for 2 weeks and oh my God — the difference! I was sat in the car today and had an attack and it just washed ov…"

Caz P.

Testimonial
Testimonial

"Linden Recovery & TRT™ Therapy changed my life. I suffered for years with panic attacks and anxiety. Within weeks of starting the program I was a different p…"

Mark T.

Testimonial
Testimonial

"I've tried CBT, medication, hypnotherapy — nothing worked until Linden Recovery & TRT™ Therapy. The science behind it finally made sense of what was happenin…"

Sarah W.

Testimonial
Testimonial

"Charles Linden is a genius. Simple as that. He understood what was happening in my brain when no doctor or therapist could explain it. His method gave me my …"

David H.

Testimonial
Testimonial

"I was housebound for three years with agoraphobia and severe anxiety. Linden Recovery & TRT™ Therapy got me out of the house, back to work, and living life a…"

Angela M.

Testimonial
Testimonial

"My daughter was suffering terribly with anxiety at age 16. Within six weeks of Linden Recovery & TRT™ Therapy she was back at school, socialising, and laughi…"

Louise B.

Testimonial
Testimonial

"I was sceptical — very sceptical. But after six months of conventional therapy going nowhere, I tried Linden Recovery & TRT™ Therapy. Three months later I ca…"

James F.

Testimonial
Testimonial

"Linden Recovery & TRT™ Therapy is the only anxiety treatment that actually addresses the cause rather than the symptoms. Everything else I tried just masked …"

Karen S.

Testimonial
Testimonial

"I've recommended Linden Recovery & TRT™ Therapy to everyone I know who struggles with anxiety. The results speak for themselves. Charles Linden has done some…"

Michael O.

Testimonial
Testimonial

"After years of CBT and medication I thought I would never be free. Linden Recovery & TRT™ Therapy showed me how to actually switch off the anxiety at its sou…"

Patricia G.

Testimonial
Testimonial

"I work as a nurse and see anxiety patients every day. I recommend Linden Recovery & TRT™ Therapy to every single one of them. The neurological explanation is…"

Susan T., RN

Testimonial
Testimonial

"Charles — you saved my marriage. My anxiety was destroying everything. Linden Recovery & TRT™ Therapy turned everything around in a matter of weeks. My husba…"

Claire R.

Testimonial
Testimonial

"I had panic disorder so severe I couldn't drive. After Linden Recovery & TRT™ Therapy I drove to Scotland from London — alone. That's the power of this program."

Tony W.

Testimonial
Testimonial

"The simplicity of Linden Recovery & TRT™ Therapy is what makes it so powerful. No complicated techniques, no pills, no side effects. Just a clear, logical pa…"

Fiona K.

"I cried when I read the testimonials on Linden Recovery & TRT™ Therapy website because I thought — finally, someone who understands. Charles Linden understan…"

Rachel H.

"My anxiety had become so bad I'd stopped eating properly, stopped seeing friends, and barely left my room. Linden Recovery & TRT™ Therapy brought me back to …"

Emily S.

"I've battled health anxiety for 20 years. Tried everything. Linden Recovery & TRT™ Therapy is the first and only thing that has actually resolved it. I genui…"

Graham L.

"Intrusive thoughts had ruined my life for 15 years. Linden Recovery & TRT™ Therapy explained why they happen and, more importantly, how to stop them. I wish …"

Nicola P.

"Social anxiety had left me isolated and unemployed. After Linden Recovery & TRT™ Therapy, I got a job, made friends, and started dating. My life has complete…"

Dan K.

"My son was suffering with OCD and anxiety at age 12. The child-appropriate version of Linden Recovery & TRT™ Therapy was incredible. He's been symptom-free f…"

Helen W.

"I flew long-haul for the first time in 11 years after completing Linden Recovery & TRT™ Therapy. I actually enjoyed the flight. I cannot describe how impossi…"

Andrew B.

"The explanation of the fear response system and how anxiety perpetuates itself was the lightbulb moment I needed. Once I understood the mechanism, Linden Rec…"

Dr. Jane M.

"Every penny spent on Linden Recovery & TRT™ Therapy was worth it. I've spent tens of thousands on therapy over 10 years with no lasting result. Linden Recove…"

Peter C.

"I thought I was broken beyond repair. My anxiety was with me every waking moment for seven years. Linden Recovery & TRT™ Therapy proved me wrong — and I am d…"

Tracey L.

Click to view all 76 written testimonials & 226 documents →

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