Table 3.

Comparison of actigraphy algorithms in accurately detecting sleep: difference in minutes between the algorithms’ estimates and the participants’ self-reports (sleep diaries).

Cohort	van Hees et al [29] sleep detection algorithma		Proposed sleep detection algorithm in this study
	Sleep onset, median (IQR)	Sleep offset, median (IQR)	Sleep onset, median (IQR)	Sleep offset, median (IQR)
Nontraumatized controls	−56 (112)	22.5 (106)	−12.5 (51)	2 (30.25)
Traumatized controls	−81 (147)	35.5 (95.5)	−18 (50)	10 (46.75)
PTSDb participants	−78 (131.25)	41.5 (122.5)	−34 (78.25)	10 (45.25)

^aFor the algorithm of van Hees et al [29], we used their implementation in the GGIR R package. The results indicate minutes of sleep onset difference and sleep offset difference between the actigraphy algorithm and the ground truth for the purpose of validation (sleep diary). For details on the distributions of the errors, see Figure 2.

^bPTSD: posttraumatic stress disorder.