Home Is Where Sleep Is: An Ecological Approach to Test the Validity of Actigraphy for the Assessment of Insomnia

Abstract

Study objectives: This study tested the ecological validity of actigraphy (ACT) for estimating objective sleep parameters in participants' homes. We also examined how well ACT and polysomnography (PSG) measures discriminated (1) individuals with and without insomnia; and (2) nights participants rated worse, the same as, or better than average. Methods: Thirty-one primary insomnia sufferers and 31 normal sleepers completed up to 3 consecutive monitoring nights with wrist ACT and PSG in their homes. They also rated how each night compared to their "average night's" sleep. ACT and PSG measures of sleep onset latency (SOL), wake after sleep onset (WASO), total sleep time (TST), and sleep efficiency (SE) were then compared using Bland and Altman correlational procedures and repeated measures ANOVAs. Differences between groups and among nights assigned distinctive ratings were tested via mixed-model ANOVAs. Results: Medium to large between-and within-subject correlations were observed for all measures in the insomnia sufferers sample and for most measures in the normal sleepers sample. Two (ACT vs. PSG) × 3 (nights) repeated measures ANOVAs showed that, in both samples, SOL derived from ACT was consistently lower than SOL derived from PSG across the 3 nights of recording. By contrast, ACT and PSG produced estimates of WASO, TST, and SE that did not differ from each other across nights. Subsequent 2 (insomnia vs. normal sleeper) × 3 (worse, same, better than average) mixed-model ANOVAs showed only ACT SOL discriminated those with and without insomnia and nights assigned distinctive ratings. Among the PSG-derived measures, only SE showed such a pattern. conclusions: ACT provides informative data for insomnia sufferers and normal sleepers in their usual sleep environments. The ACT estimate of SOL seems sensitive to night-to-night differences in subjective sleep ratings. A possible strength of ACT lies in its assessment of nocturnal movement, a parameter different from PSG-based sleep measures.

Effect of Total Sleep Deprivation in Visual Sequential Memory

“…This empirical demonstration is merely a beginning of our investigation in a particular cultural context, Bangladesh, which would lead us to a computational cognitive process model in order to find a mechanistic explanation of the behaviour dynamics in future. The findings are strongly supported by ecological validity (Dickinson et al, 2017;Sánchez-Ortuño et al, 2010). Things are always assumed to be happened normally and can better be explained in natural settings rather than strict lab control where human subjects are observed.…”

“…Participants were taken to the laboratory 12 hours before the test of VSM was administered. Subjects were allowed to follow their normal everyday activities in day time, which in turn ensured the ecological validity of the study (Dickinson, Drummond, & McElroy, 2017;Sánchez-Ortuño, Edinger, Means, & Almirall, 2010). Subjects were given full one-night adaptation in the lab prior testing.…”

Calibrating actigraphy to improve sleep efficiency estimates

“…It extends this finding to anxiety‐disordered patients measured in the home. The correlation of calibrated ACT‐SE and PSG‐SE in this study was modestly higher than in previous home studies using clinical samples (Baandrup and Jennum, ; Sanchez‐Ortuno et al ., ).…”

“…Representing the third category, Blackwell and colleagues conducted two large home‐based studies with community‐dwelling women and men at risk for osteoporotic fractures and found intraclass correlation coefficients (ICCs) between ACT‐SE and PSG‐SE ranging from 0.16 to 0.61 (Blackwell et al ., , ). In a non‐sleep‐disordered subsample studied in the home, Sanchez‐Ortuno observed a non‐significant ACT‐SE/PSG‐SE correlation of 0.23 (Sanchez‐Ortuno et al ., ). Only two studies have compared ACT‐SE with PSG‐SE in adults with sleep complaints studied in the home.…”

“…Only two studies have compared ACT‐SE with PSG‐SE in adults with sleep complaints studied in the home. In an insomniac subsample screened for primary sleep disorders, Sanchez‐Ortuno observed a correlation of 0.41 between ACT‐SE and PSG‐SE (Sanchez‐Ortuno et al ., ), suggesting that ACT‐SE explained only approximately 16% of the variance in gold‐standard PSG‐SE. Moreover, while PSG‐SE exhibited a main effect of insomnia group, ACT‐SE did not.…”