Condition category
Mental and Behavioural Disorders
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
On the basis of a well established and proven theory for controlled respiration as a behavioural intervention for common mental health disorders (CMHD) and evidence that gamification can improve health outcomes through increasing patients’ engagement, we have developed an mHealth game called Flowy, which is the first mHealth app to operationalize breathing retraining exercises for gameplay. We have designed Flowy to bridge intervention accessibility gaps, reduce the economic burden of chronic mental illness, endorse personalized patient-centered care, and engage users to understand and manage their own condition in a fun and meaningful way. We have engaged service users with CMHDs, their families and their care providers in Flowy’s design, development and pilot evaluation. The study aims are to assess the acceptability of Flowy as a mobile health game that digitally delivers breathing retraining exercises for anxiety, panic and hyperventilation symptom management in people with moderate anxiety; the effectiveness in reducing symptom severity alongside improving quality of life; and both the user engagement and usability.

Who can participate?
Adults with anxiety disorders

What does the study involve?
Patients were randomly allocated to one of two groups. The intervention group played Flowy for 1 month and the control group patients were placed on a waiting list for 1 month and then given a code to download Flowy.

What are the possible benefits and risks of participating?
The possible benefits include an improvement in the patient’s condition and the development of a new management tool for similar conditions. There are no known risks associated with breathing retraining exercises.

Where is the study run from?
Wolfson Institute for Preventive Medicine (UK) and Playlab London (UK)

When is the study starting and how long is it expected to run for?
From February 2014 to July 2014

Who is funding the study?
Playlab London (UK)

Who is the main contact?
Ms Quynh Pham

Trial website

Contact information



Primary contact

Ms Quynh Pham


Contact details

Playlab London
71b St John Street
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Feasibility and efficacy of an mHealth game for managing anxiety: Flowy randomized controlled pilot trial and design evaluation


Study hypothesis

A breathing retraining game Flowy will be an acceptable, clinically effective, engaging and useful anxiety management intervention:
1. Determine the feasibility of Flowy as an anxiety management intervention
2. Validate the clinical efficacy of Flowy to measurably reduce clinical symptoms

Ethics approval

Queen Mary Research Ethics Committee (Panel B), 19/03/2014, QMREC2014/20

Study design

Interventional randomized controlled pilot study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet



Anxiety disorders


1. Intervention group: Flowy is an mHealth game that engages users in a series of mini games where they use breathing retraining exercises and perform diaphragmatic breathing to alleviate anxiety. These mini games range from sailing a boat down a river to flying balloons in the sky. Users touch the screen with their finger as they inhale and remove their finger from the screen as they exhale to control the gaming mechanics. A breathing indicator visually represents a full breath; users see a circle expanding as they inhale and contracting as they exhale. This indicator provides a visual guideline of a breathing retraining exercise, and also simplifies the cognitive assessment of what constitutes a full diaphragmatic breath. The goal of each mini game is to correctly follow the breathing indicator while advancing in the game narrative; users win by breathing correctly and staying calm. No usage guidelines were enforced to allow for assessment of naturalistic use patterns determined by the patient. Flowy also includes an in-game interactive tutorial on how to properly perform diaphragmatic breathing, as guided by the National Health Service Improving Access to Psychological Therapies protocol alongside evidence-based research protocol from literature.
2. Control group: participants were placed on a waiting list for 4 weeks. To prevent high attrition rates, participants received a weekly newsletter with curated content on breathing retraining exercises, Flowy game development, mindfulness meditation and similar content relevant to Flowy. Additionally, they received reminder emails through an online marketing tool MailChimp to complete study assessments. After 4 weeks, participants received a free code to download Flowy.

Intervention type



Drug names

Primary outcome measure

Acceptability of Flowy as an anxiety management intervention, assessed with recruitment and response rates throughout the study

Secondary outcome measures

1. Whether Flowy engaged participants sufficiently to make them proactively use the application, assessed by frequency and duration of use based on log data throughout the study
2. A significant reduction in anxiety, panic and hyperventilation symptoms and improvement in quality of life reported by participants in the intervention group from baseline to week 4, measured at eligibility prescreen, baseline, week 2 and week 4
3. A significant reduction in anxiety, panic and hyperventilation symptoms and improvement in quality of life reported by participants in the intervention group compared with the control group from baseline to week 4, measured at eligibility prescreen, baseline, week 2 and week 4
4. Participant perception of Flowy as a useful intervention, measured with a 21-question questionnaire that assesses intervention usability and utility at week 4
5. Assessment of the outcome measure scores in pilot study participants to establish parameters of measurable change in anxiety, hyperventilation and panic attack symptoms for a subsequent full-powered and full-scale randomized controlled trial
6. Study design evaluation to inform sample size calculation and methodology of a subsequent full-powered and full-scale randomized controlled trial

Anxiety symptoms were assessed with three questionnaires: Generalized Anxiety Disorder-7 (GAD-7) item scale, Overall Anxiety Severity and Impairment Scale (OASIS) and Anxiety Sensitivity Index-3 (ASI-3).

Panic symptoms were assessed with the Panic Disorder Severity Scale-Self Report (PDSS-SR).

Hyperventilation symptoms were assessed with the Nijmegen Questionnaire.

Quality of life, enjoyment and satisfaction were assessed with the Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Age at least 18 years old
2. Screen GAD-7 score ≥6
3. Screen OASIS score ≥8
4. Screen ASI-3 score ≥16
5. Comorbid disorders including major depression, dysthymia, panic disorder, agoraphobia, social anxiety disorder, generalized anxiety disorder, simple phobia, obsessive compulsive disorder, and somatization disorder with moderate symptoms of anxiety
6. Concurrent use of antidepressants, anxiolytics, hypnotics, and herbal products with psychoactive substances acceptable provided there is no change in medication type and dose after randomization
7. Provision of written informed consent
8. Able to comply with the study protocol (e.g., able to download Flowy onto mobile device or able to complete assessments)

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Lack of mobile device or incompatible operating system (Android and iOS compatibility required)
2. Lack of access to Internet
3. Any co-existing medical conditions that could alter the clinical presentation of hyperventilation such as chronic severe asthma or chronic obstructive pulmonary disease
4. Lifetime history of bipolar disorder or psychosis
5. Presence of any Diagnostic and Statistical Manual of Mental Disorders (DSM) IV Axis I disorder, excluding those listed in the inclusion criteria, that are likely to interfere with the patient’s ability to participate in the study, as judged by the investigator
6. Presence of any DSM-IV Axis II disorder that are likely to interfere with the patient’s ability to participate in the study, as judged by the investigator
7. Participants who are acutely suicidal to the degree that precautions against suicide are needed or have a history of suicide attempt in the past 5 years

Recruitment start date


Recruitment end date



Countries of recruitment

Argentina, Brazil, Canada, Cyprus, Germany, Israel, Italy, Malaysia, United Kingdom, United States of America

Trial participating centre

Playlab London
71b St John Street
United Kingdom

Sponsor information


Queen Mary University of London

Sponsor details

Queens’ Building
Queen Mary University of London
Mile End Road
E1 4NS
United Kingdom

Sponsor type




Funder type


Funder name

Playlab London

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

We aim to publish our findings in the Journal of Medical Internet Research (impact factor: 4.7)

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

2016 results in

Publication citations

Additional files

Editorial Notes

20/03/2020: Internal review. 03/10/2017: Internal review 10/08/2017: Publication reference added.