BACKGROUND
Several studies have recently reported on the correlation between objective behavioral features collected via mobile and wearable technologies and depressive mood symptoms in affective disorders (unipolar disorder and bipolar disorder). However, individual studies have reported on different and sometimes contradicting results, and no quantitative systematic review of the correlation between objective behavioral features and depressive mood symptoms has been published.
OBJECTIVE
The objectives of this systematic review were to 1) provide an overview of correlations between objective behavioral features and depressive mood symptoms reported in the literature, and 2) investigate the strength and statistical significance of these correlations across studies. The answers to these questions could potentially help in the identification on which objective features have shown most promising results across studies.
METHODS
A systematic review of the scientific literature reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines was conducted. IEEE Xplore, ACM Digital Library, Web of Sciences, PsychINFO, Pubmed, DBLP computer science bibliography, HTA, DARE, Scopus and Science Direct were searched and supplemented by hand examination of reference lists. The search ended 04/27-2017 and was limited to studies published 2007-2017.
RESULTS
A total of 46 studies were eligible for the review. These studies identified and investigated 85 unique objective behavioral features covering 17 various sensor data inputs. These features can be categorized into seven overall categories. Several features were found to have statistically significant and consistent correlation directionality with mood assessment (e.g., the amount of home stay, sleep duration, vigorous activity), while others showed directionality discrepancies across the studies (e.g., amount of SMS sent, time you spend between locations, frequency of smartphone screen activity).
CONCLUSIONS
Several studies showed consistent and statistically significant correlations between objective behavioral features collected by mobile and wearable technology and depressive mood symptoms. Hence, continuous and every-day monitoring of behavioral aspects in affective disorders could be a promising supplementary objective measure to estimate depressive mood symptoms. However, the evidence is limited by methodological issues in individual studies and by a lack of standardization of 1) the collected objective features, 2) the mood assessment methodology, and 3) the statistical methods applied. Therefore, consistency in data collection and analysis in future studies is needed making replication studies as well as meta-analyses possible.
Correlations Between Objective Behavioral Features Collected From Mobile and Wearable Devices and Depressive Mood Symptoms in Patients With Affective Disorders: Systematic Review
