TY - JOUR
T1 - Fragmentation as a novel measure of stability in normalized trajectories of mood and attention measured by ecological momentary assessment
AU - Johns, Jordan T.
AU - Di, Junrui
AU - Merikangas, Kathleen
AU - Cui, Lihong
AU - Swendsen, Joel
AU - Zipunnikov, Vadim
N1 - Funding Information:
This research was supported by the Intramural Research Program of the National Institute of Mental Health (Grant Z-01-MH002804 awarded to Kathleen Merikangas) and was conducted under clinical protocol 03-M-0211 (NCT00071786). The views and opinions expressed in this article are those of the authors and should not be construed to represent the views of any of the sponsoring organizations, agencies, or the U.S. Government.
Publisher Copyright:
© 2018 American Psychological Association.
PY - 2019/3
Y1 - 2019/3
N2 - Electronic diary data, such as that acquired through Ecological Momentary Assessments (EMA), has historically provided novel insights into diverse psychological processes. Analyses of these data typically focus on modeling participant-specific means, variability, and stability. We propose a novel statistical framework to determine participant stability by quantifying fragmentation of standardized trajectories using the following 2-step approach: (1) participant-level EMA scores are normalized, and (2) normalized scores are dichotomized into 2 states, inside and outside a range of 1 standard deviation. Withinparticipant fragmentation measures were calculated from dichotomized scores and modeled with various covariates. We used this method to study patterns of emotional states and showed that the proposed fragmentation measures differentiate mood disorder subtypes, including Bipolar I (BPI), Bipolar II, and major depressive disorder (MDD) compared with unaffected controls. Fragmentation measures were regressed on the mood disorder subtype, adjusting for age, sex, body mass index, and mean squared successive difference. The analyses revealed decreased stability (more fragmentation) among those with BPI when inside the participant-specific standard range of attention (β = 0.09, p =.004) and decreased stability among those with MDD inside the standard range of mood (β = 0.04, p =.039) and attention (β = 0.05, p =.017). This work provides an illustration of the clinical significance of EMA in characterizing the stability of mood, attention, or other psychological states that may underlie psychological disorders and phenomena. The application of fragmentation provides a novel statistical approach that can characterize within-participant stability beyond currently available traditional approaches.
AB - Electronic diary data, such as that acquired through Ecological Momentary Assessments (EMA), has historically provided novel insights into diverse psychological processes. Analyses of these data typically focus on modeling participant-specific means, variability, and stability. We propose a novel statistical framework to determine participant stability by quantifying fragmentation of standardized trajectories using the following 2-step approach: (1) participant-level EMA scores are normalized, and (2) normalized scores are dichotomized into 2 states, inside and outside a range of 1 standard deviation. Withinparticipant fragmentation measures were calculated from dichotomized scores and modeled with various covariates. We used this method to study patterns of emotional states and showed that the proposed fragmentation measures differentiate mood disorder subtypes, including Bipolar I (BPI), Bipolar II, and major depressive disorder (MDD) compared with unaffected controls. Fragmentation measures were regressed on the mood disorder subtype, adjusting for age, sex, body mass index, and mean squared successive difference. The analyses revealed decreased stability (more fragmentation) among those with BPI when inside the participant-specific standard range of attention (β = 0.09, p =.004) and decreased stability among those with MDD inside the standard range of mood (β = 0.04, p =.039) and attention (β = 0.05, p =.017). This work provides an illustration of the clinical significance of EMA in characterizing the stability of mood, attention, or other psychological states that may underlie psychological disorders and phenomena. The application of fragmentation provides a novel statistical approach that can characterize within-participant stability beyond currently available traditional approaches.
KW - Bipolar disorder
KW - Ecological momentary assessment
KW - Fragmentation
KW - Major depressive disorder
KW - Stability
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U2 - 10.1037/pas0000661
DO - 10.1037/pas0000661
M3 - Article
C2 - 30802118
AN - SCOPUS:85062067859
SN - 1040-3590
VL - 31
SP - 329
EP - 339
JO - Psychological Assessment
JF - Psychological Assessment
IS - 3
ER -