Cited by 110Digital Mental Health InterventionsMental Health Research TopicsMobile Health and mHealth Applications

The DOI matches its Crossref record; 55 of the 55 references it cites were found in a registry or an index; 2 of the 39 sources its claims cite were checked for support.

Remote Assessment of Disease and Relapse in Major Depressive Disorder (RADAR-MDD): recruitment, retention, and data availability in a longitudinal remote measurement study

Open access

Published version of a preprint

Abstract

Background: Major Depressive Disorder (MDD) is prevalent, often chronic, and requires ongoing monitoring of symptoms to track response to treatment and identify early indicators of relapse. Remote Measurement Technologies (RMT) provide an opportunity to transform the measurement and management of MDD, via data collected from inbuilt smartphone sensors and wearable devices alongside app-based questionnaires and tasks. A key question for the field is the extent to which participants can adhere to research protocols and the completeness of data collected. We aimed to describe drop out and data completeness in a naturalistic multimodal longitudinal RMT study, in people with a history of recurrent MDD. We further aimed to determine whether those experiencing a depressive relapse at baseline contributed less complete data. Methods: Remote Assessment of Disease and Relapse – Major Depressive Disorder (RADAR-MDD) is a multi-centre, prospective observational cohort study conducted as part of the Remote Assessment of Disease and Relapse – Central Nervous System (RADAR-CNS) program. People with a history of MDD were provided with a wrist-worn wearable device, and smartphone apps designed to: a) collect data from smartphone sensors; and b) deliver questionnaires, speech tasks, and cognitive assessments. Participants were followed-up for a minimum of 11 months and maximum of 24 months. Results: Individuals with a history of MDD ( n = 623) were enrolled in the study,. We report 80% completion rates for primary outcome assessments across all follow-up timepoints. 79.8% of people participated for the maximum amount of time available and 20.2% withdrew prematurely. We found no evidence of an association between the severity of depression symptoms at baseline and the availability of data. In total, 110 participants had > 50% data available across all data types. Conclusions: RADAR-MDD is the largest multimodal RMT study in the field of mental health. Here, we have shown that collecting RMT data from a clinical population is feasible. We found comparable levels of data availability in active and passive forms of data collection, demonstrating that both are feasible in this patient group.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

RADAR-MDD enrolled 623 people with recurrent major depressive disorder across three sites and followed them for 11–24 months using smartphone and wearable remote measurement technologies. The study reports high retention and outcome completion (~80%) and comparable active/passive data availability, with no convincing evidence that baseline depression symptom severity predicts data availability.

Key findings

  • Of 623 enrolled participants, 497 (79.8%) participated for the maximum possible duration and 126 (20.2%) withdrew prematurely; completion of primary and secondary outcomes was approximately 80% across follow-up, with 445 (71.4%) providing 1-year outcome data and 181 (29.1%) participating for a full 2 years.
  • Median study participation was 541 days (IQR 401–730); 2.9 terabytes of compressed data were collected, and 110 participants (17.7%) had >50% available data across all modes of data collection.
  • Active RMT: participants completed median 21 PHQ-8 questionnaires, 20 RSES questionnaires, and 12 speech tasks; any data were available for 95.3% (PHQ8), 94.5% (RSES), and 82.2% (speech). THINC-it tasks had median 5 completions each, with >84% of participants having any data for each test.
  • Wearable RMT: average Fitbit wear-time was 62.5% (SD 9.1 percentage points) and mean 15.1 h/day; step count was most available (~50% provided >75% expected data), while activity data were least available (only 5% had >75%). Activity availability differed by baseline depression status (X² = 14.1, p = 0.002); passive smartphone data showed no evidence of difference by baseline depression in the narrative.

Methods

  • Multi-centre, prospective observational cohort study (RADAR-MDD) within RADAR-CNS; 623 adults with recurrent MDD (DSM-5 non-psychotic MDD within past 2 years and ≥2 lifetime episodes) were recruited at King’s College London (UK), Amsterdam University Medical Centre (Netherlands), and CIBER (Barcelona, Spain), with follow-up of 11–24 months.
  • Participants used a wrist-worn Fitbit Charge 2/3, RADAR-base active and passive smartphone apps (questionnaires, speech tasks, ESM, smartphone sensors), a THINC-it cognitive app, and REDCap outcome surveys every 3 months.
  • Analyses described baseline characteristics; compared baseline symptomatic vs no/some depression symptoms using chi-squared tests, linear regressions, and t-tests for ESM; summarised data availability in quartiles; estimated Fitbit wear time from heart-rate values >0 per 15-min window; used STATA v16.0.

Limitations

  • Stated: sensor and data types have different temporal validity and aggregation requirements, making coherent summary challenging; iterative RADAR-base/app changes meant participants had different user experiences over time; COVID-19 may have affected research experience and data completion; the sample had a higher proportion of White and female individuals than typical populations, limiting generalisability; the paper describes data availability, not quality or completeness, and does not examine predictors of availability.
  • Evident from the text: “available” data may include complete, partial, corrupted, or invalid data; baseline depression status is static and may not capture symptom fluctuations relevant to technology use; no formal threshold for acceptable dropout is established, though the authors describe ~80% completion as excellent.

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Integrity signals

Registry

Crossref · 10.1186/s12888-022-03753-1

Cites

55 of 55 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Figures

Fig. 1 STROBE flowchart for recruitment into RADAR-MDD
Fig. 1 STROBE flowchart for recruitment into RADAR-MDDCC BY · PubMed Central
Fig. 2 Participants “not contacted” because they had already completed the maximum amount of follow-up time or had already withdrawn from the study. Participants were “contacted” when they were still active participants. *Reasons for withdrawal provided in Supplementary file 4. **Invalid outcomes collected ±21 days of due date
Fig. 2 Participants “not contacted” because they had already completed the maximum amount of follow-up time or had already withdrawn from the study. Participants were “contacted” when they were still active participants. *Reasons for withdrawal provided in Supplementary file 4. **Invalid outcomes collected ±21 days of due dateCC BY · PubMed Central
Fig. 3 Questionnaires triggered every 2 weeks; maximum number of possible responses: 52. 3a: 8-item Patient Health Questionnaire (PHQ8); 3b: Rosenberg Self-Esteem Scale (RSES); 3c: Speech data
Fig. 3 Questionnaires triggered every 2 weeks; maximum number of possible responses: 52. 3a: 8-item Patient Health Questionnaire (PHQ8); 3b: Rosenberg Self-Esteem Scale (RSES); 3c: Speech dataCC BY · PubMed Central
Fig. 4 Questionnaires triggered every 6 weeks; maximum number of possible responses: 17. 4a: 5-item Perceived Deficits Questionnaire (PDQ5); 4b: Code Breaker; 4c: Spotter; 4d: Symbol Check; 4e: Trails
Fig. 4 Questionnaires triggered every 6 weeks; maximum number of possible responses: 17. 4a: 5-item Perceived Deficits Questionnaire (PDQ5); 4b: Code Breaker; 4c: Spotter; 4d: Symbol Check; 4e: TrailsCC BY · PubMed Central
Fig. 5 A) Heatmap representing study day and data points per hour. B) percentage wear time stratified by baseline depression status
Fig. 5 A) Heatmap representing study day and data points per hour. B) percentage wear time stratified by baseline depression statusCC BY · PubMed Central

Verification

Claims the paper makes

60 Own result · 27 Not checked yet · 16 Own interpretation · 6 No basis given · 3 Own method · 2 Partly supported · accuracy not yet measured

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Show all 66 claims

  • It may state two separate claims as one. 32
  • Probably not a substantial claim. 22
48 of 48
  • The authors state this as an assumption.

    Data availability is a valid indicator of the feasibility of implementing RMT protocols in people with MDD.

    “We believe it is essential to include partial or incomplete data as part of this paper, as they are indicative not only of participant characteristics and study burden, but also of the underlying technical infrastructure.”
    “This concession gives greater insight into how data availability may fluctuate with changes in depressive state and provides a truer representation of the feasibility of implementing RMT protocols in people with MDD.”
  • The paper relies on this without support.

    The RADAR-MDD sample of people with a history of recurrent MDD is representative of the clinical population with MDD for assessing feasibility of RMT.

    “Here, we have shown that collecting RMT data from a clinical population is feasible.”
  • The paper relies on this without support.

    No remote measurement studies have reported the quantity of data collected via smartphone sensors.

    “To the best of our knowledge, no remote measurement studies have reported the quantity of data collected via smartphone sensors.”
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Metadata

Authors
Matcham, F., Leightley, D., Siddi, S., Lamers, F., White, K. M., Annas, P., de Girolamo, G., Difrancesco, S., Haro, J. M., Horsfall, M., Ivan, A., Lavelle, G., Li, Q., Lombardini, F., Mohr, D. C., Narayan, V. A., Oetzmann, C., Penninx, B. W. J. H., Bruce, S., Nica, R., Simblett, S. K., Wykes, T., Brasen, J. C., Myin-Germeys, I., Rintala, A., Conde, P., Dobson, R. J. B., Folarin, A. A., Stewart, C., Ranjan, Y., Rashid, Z., Cummins, N., Manyakov, N. V., Vairavan, S., Hotopf, M., & on behalf of the RADAR-CNS consortium
Affiliations
  • King's College London (GB)
  • Centro de Investigación Biomédica en Red de Salud Mental (ES)
  • Amsterdam Public Health (NL)
  • Lundbeck (Denmark) (DK)
  • Northwestern University (US)
  • LAB University of Applied Sciences (FI)
  • Janssen (Belgium) (BE)
Corresponding author
Matcham, Faith
Venue
BMC Psychiatry
Published
2022-02-21
Volume
22
Issue
1
Pages
136-136
ISSN
1471-244X (ISSN-L)
OpenAlex
W4225751944
Cited by
110
References
55
Citations by year
2026: 18 · 2025: 26 · 2024: 35 · 2023: 16 · 2022: 14
FWCI
20.04
Type
journal article
Language
en
Open access
Locations
  • BMC Psychiatry (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Research Portal (King's College London) (publishedVersion, cc-by)
  • Pure Amsterdam UMC (publishedVersion, other-oa)
  • Amsterdam UMC (VU Amsterdam) - Institutional Repository (publishedVersion, other-oa)
  • Lirias (submittedVersion, cc-by)
  • OPUS (Augsburg University) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Data Archiving and Networked Services (DANS) (submittedVersion, other-oa)
Funders
  • NHS Blood and Transplant
  • South London and Maudsley NHS Foundation Trust
  • Wellcome Trust (116074)
  • King's College Hospital NHS Foundation Trust
  • Scottish Government
  • European Federation of Pharmaceutical Industries and Associations (116074)
  • UK Research and Innovation
  • Alzheimer's Society
  • National Institute for Health and Care Research (NF-SI-0515-10102, 116074)
  • British Heart Foundation
  • Department of Health and Social Care
  • King's College London
  • University College London
  • European Commission (115902, 116074, HORIZON2020)
  • Public Health Agency
  • ZonMw (73305095003)
  • King's Health Partners
  • Innovative Medicines Initiative (116074)
  • Institut Català de la Salut
  • GIESKES-STRIJBIS FONDS
  • Chief Scientist Office, Scottish Government Health and Social Care Directorate
  • NIHR BioResource
  • NIHR Maudsley Biomedical Research Centre
  • Medical Research Council (MC_PC_17214)
  • Engineering and Physical Sciences Research Council
  • Economic and Social Research Council
  • Health and Social Care Research and Development Division
  • National Institute for Health Research Applied Research Collaboration South London
  • Health Data Research UK
Topics
  • Social Sciences › Psychology › Applied Psychology › Digital Mental Health Interventions
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Mental Health Research Topics
  • Health Sciences › Health Professions › General Health Professions › Mobile Health and mHealth Applications
Keywords
major depressive disorder, recurrent depression, depression relapse, wearable devices, smartphone sensors, participant recruitment and retention, data completeness, multimodal data collection, passive data collection
MeSH terms
Smartphone, Chronic Disease, Major Depressive Disorder, Humans, Prospective Studies, Recurrence, Mobile Applications

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