Comparing a Fitbit Wearable to an Electrocardiogram Gold Standard as a Measure of Heart Rate Under Psychological Stress: A Validation Study.

BACKGROUND: Wearable devices collect physiological and behavioral data that have the potential to identify individuals at risk of declining mental health and well-being. Past research has mainly focused on assessing the accuracy and the agreement of heart rate (HR) measurement of wearables under different physical exercise conditions. However, the capacity of wearables to sense physiological changes, assessed by increasing HR, caused by a stressful event has not been thoroughly studied. OBJECTIVE: This study followed 3 objectives: (1) to test the ability of a wearable device (Fitbit Versa 2) to sense an increase in HR upon induction of psychological stress in the laboratory; (2) to assess the accuracy of the wearable device to capture short-term HR variations caused by psychological stress compared to a gold-standard electrocardiogram (ECG) measure (Biopac); and (3) to quantify the degree of agreement between the wearable device and the gold-standard ECG measure across different experimental conditions. METHODS: Participants underwent the Trier Social Stress Test protocol, which consists of an oral phase, an arithmetic stress phase, an anticipation phase, and 2 relaxation phases (at the beginning and the end). During the stress protocol, the participants wore a Fitbit Versa 2 and were also connected to a Biopac. A mixed-effect modeling approach was used (1) to assess the effect of experimental conditions on HR, (2) to estimate several metrics of accuracy, and (3) to assess the agreement: the Bland-Altman limits of agreement (LoA), the concordance correlation coefficient, the coverage probability, the total deviation index, and the coefficient of an individual agreement. Mean absolute error and mean absolute percent error were calculated as accuracy indices. RESULTS: A total of 34 university students were recruited for this study (64% of participants were female with a mean age of 26.8 years, SD 8.3). Overall, the results showed significant HR variations across experimental phases. Post hoc tests revealed significant pairwise differences for all phases. Accuracy analyses revealed acceptable accuracy according to the analyzed metrics of accuracy for the Fitbit Versa 2 to capture the short-term variations in psychological stress levels. However, poor indices of agreement between the Fitbit Versa 2 and the Biopac were found. CONCLUSIONS: Overall, the results support the use of the Fitbit Versa 2 to capture short-term stress variations. The Fitbit device showed acceptable levels of accuracy but poor agreement with an ECG gold standard. Greater inaccuracy and smaller agreement were found for stressful experimental conditions that induced a higher HR. Fitbit devices can be used in research to measure HR variations caused by stress, although they cannot replace an ECG instrument when precision is of utmost importance.

Measurement Based Care in a first episode psychosis program: Development of an algorithm of care based on the Clinical Global Impressions Scale.

INTRODUCTION: Adherence to therapeutic guidelines in psychiatry is anchored and facilitated by rating scales. However, they are rarely used in routine care, particularly for psychotic disorders. Consequently, adherence to treatment guidelines are not ideal and patient outcomes are often sub-optimal. In this study, we used the clinician-rated Clinical Global Impressions Scale (CGI) to implement a measurement-based care (MBC) approach and derive indices of quality of care at a first episode psychosis (FEP) program. METHODS: At the individual level, an algorithm was created using CGI scores and their changes over time to define the concept of Patient Requiring Clinical Attention (PRCA) that encompasses several categories (e.g. episode of severity, treatment inertia, or treatment resistance). At the service level, CGI scores were used to derive several indices of quality of care: severity of illness and its change over time, conformity to the use of low doses of antipsychotic medications, and clozapine offer index. RESULTS: 135 Patients were included in this study of whom 19 patients were identified as PRCA. Of these, 12 (63%) received timely medication, and 7 (37%) were suspected cases of therapeutic inertia. Additionally, 15 patients met criteria for treatment resistance of whom 7 were offered clozapine (47%). At the service level, the average CGI improved by 2 points from baseline to month 1 and average doses of antipsychotic medications prescribed were in line with prescription guidelines for FEP patients. CONCLUSION: The proposed CGI-based treatment algorithm and service evaluation strategy can help to optimize quality care and services for patients.

Pragmatic implementation of the Clinical Global Impression Scale of Severity as a tool for measurement-based care in a first-episode psychosis program.

INTRODUCTION: Measurement-based care (MBC) is an evidence-based practice wherein clinical decisions are informed by patient data collected throughout treatment. MBC has yielded superior patient outcomes compared to standard care. However, the implementation of MBC in the day-to-day practice, particularly in psychotic disorders, poses several challenges. This study evaluates the clinician-rated Clinical Global Impressions Scale of Severity (CGI-S), for MBC implementation at a first-episode psychosis program. METHODS: The CGI-S was evaluated in the context of routine care on fidelity to practice, inter-rater reliability among psychiatrists and concurrent validity with scales measuring different domains of psychopathology (SAPS, SANS, GAF, BPRS, PANSS-6). RESULTS: A high fidelity to practice (67%) and inter-rater reliability was found (rwg = 0.92). CGI-S correlations were significant and strongest with BPRS (r = 0.55; p < 0.01), GAF (r = 0.53; p < 0.01), SAPS (r = 0.52, p < 0.01), and PANSS-6 (r = 0.41; p < 0.05) scores. However, correlations with SANS and PANSS-6 Negative sub-scale were weak. CONCLUSION: Findings suggest the CGI may be used to overcome important barriers towards MBC implementation within the context of first episode psychosis. However, as suggested by data, further improvements in capturing negative symptoms by rating clinicians are needed. TWITTER: A novel strategy for measurement-based care to optimize treatment for individuals with first episode psychosis and related psychotic disorders.