Nonlinear time-series approaches in characterizing mood stability and mood instability in bipolar disorder by M. B. Bonsall, S. M. A. Wallace-Hadrill, J. R. Geddes, G. M. Goodwin, and E. A. Holmes Proceedings B Volume 279(1730): March 7, 2012 ©2012 by The Royal Society

A schematic of mood patterns in bipolar disorder: the disorder does not simply feature full- blown episodes of mania and depression with periods of normality. M. B. Bonsall et al. Proc. R. Soc. B 2012;279: ©2012 by The Royal Society

Illustration of the type of mood score charts used to rate patients in clinic as either stable or unstable. M. B. Bonsall et al. Proc. R. Soc. B 2012;279: ©2012 by The Royal Society

Patient attrition rates from the study over 220 weeks. M. B. Bonsall et al. Proc. R. Soc. B 2012;279: ©2012 by The Royal Society

Mood score time series for individual patients from the stable group (black lines) with fitted threshold autoregressive model (equations (3.1) and (3.2); red and blue points). M. B. Bonsall et al. Proc. R. Soc. B 2012;279: ©2012 by The Royal Society

Mood score time series for individual patients from the unstable group (black lines) with fitted threshold autoregressive model (equations (3.3) and (3.4); red and blue points). M. B. Bonsall et al. Proc. R. Soc. B 2012;279: ©2012 by The Royal Society