title: Daily longitudinal self-monitoring of mood variability in bipolar disorder and borderline personality disorder.
abstract: Traditionally, assessment of psychiatric symptoms has been relying on their retrospective report to a trained interviewer. The emergence of smartphones facilitates passive sensor-based monitoring and active real-time monitoring through time-stamped prompts; however there are few validated self-report measures designed for this purpose.
  
  
  
  We introduce a novel, compact questionnaire, Mood Zoom (MZ), embedded in a customised smart-phone application. MZ asks participants to rate anxiety, elation, sadness, anger, irritability and energy on a 7-point Likert scale. For comparison, we used four standard clinical questionnaires administered to participants weekly to quantify mania (ASRM), depression (QIDS), anxiety (GAD-7), and quality of life (EQ-5D). We monitored 48 Bipolar Disorder (BD), 31 Borderline Personality Disorders (BPD) and 51 Healthy control (HC) participants to study longitudinal (median±iqr: 313±194 days) variation and differences of mood traits by exploring the data using diverse time-series tools.
  
  
  
  MZ correlated well (|R|>0.5,p<0.0001) with QIDS, GAD-7, and EQ-5D. We found statistically strong (|R|>0.3,p<0.0001) differences in variability in all questionnaires for the three cohorts. Compared to HC, BD and BPD participants exhibit different trends and variability, and on average had higher self-reported scores in mania, depression, and anxiety, and lower quality of life. In particular, analysis of MZ variability can differentiate BD and BPD which was not hitherto possible using the weekly questionnaires.
  
  
  
  All reported scores rely on self-assessment; there is a lack of ongoing clinical assessment by experts to validate the findings.
  
  
  
  MZ could be used for efficient, long-term, effective daily monitoring of mood instability in clinical psychiatric practice.
authors.affiliation: Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, UK; Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, UK; Sleep and Circadian Neuroscience Institute, Nuffield Department of Clinical Neurosciences, UK. Electronic address: athanasios.tsanas@eng.ox.ac.uk.
authors.forename: A
authors.initials: A
authors.lastname: Tsanas
authors.affiliation: Department of Psychiatry, University of Oxford, UK.
authors.forename: K E A
authors.initials: KE
authors.lastname: Saunders
authors.affiliation: Department of Psychiatry, University of Oxford, UK.
authors.forename: A C
authors.initials: AC
authors.lastname: Bilderbeck
authors.affiliation: Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, UK.
authors.forename: N
authors.initials: N
authors.lastname: Palmius
authors.affiliation: Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, UK.
authors.forename: M
authors.initials: M
authors.lastname: Osipov
authors.affiliation: Department of Biomedical Informatics, Emory University, Atlanta, GA, USA; Department of Biomedical Engineering, Georgia Institute of Technology, USA.
authors.forename: G D
authors.initials: GD
authors.lastname: Clifford
authors.affiliation: Department of Psychiatry, University of Oxford, UK.
authors.forename: G Μ
authors.initials: GΜ
authors.lastname: Goodwin
authors.affiliation: Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, UK; Sleep and Circadian Neuroscience Institute, Nuffield Department of Clinical Neurosciences, UK.
authors.forename: M
authors.initials: M
authors.lastname: De Vos
mesh_terms: D000293:Adolescent; D000328:Adult; D000339:Affect; D000786:Anger; D001007:Anxiety / Q000523:psychology*; D001714:Bipolar Disorder / Q000523:psychology*; D001883:Borderline Personality Disorder / Q000523:psychology*; D003863:Depression / Q000523:psychology*; D005260:Female; D006801:Humans; D007508:Irritable Mood; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D057566:Self Report; D012647:Self-Assessment; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Bipolar disorder; Borderline personality disorder; Digital health; Mood assessment; Mood monitoring; Patient reported outcome measures