Health

Two paradigms have shaped the way sleep is studied. The first prizes precision under controlled conditions and produces the high-resolution polysomnography traces that remain the diagnostic standard for sleep architecture. The second prizes ecological validity and produces the multi-week behavioral recordings that capture how participants actually sleep at home. Both paradigms answer real questions, and both fall short when used in isolation. Modern protocols increasingly draw from both, with research-grade multi-week recording platforms such as ActTrust 2  filling the role that home-based instrumentation needs to play. The Strengths and Limits of Polysomnography Polysomnography records EEG, EOG, EMG, respiratory effort, and oxygenation, which is the only way to stage REM and NREM sleep with current technology. That precision comes at a cost. Lab nights are unfamiliar, expensive, and unrepresentative of typical home sleep. The first-night effect alone introduces measurable distorti...

Learn how data harmonization improves accuracy in multi-vendor actigraphy studies by aligning actigraph outputs, sleep diary inputs, and light sensor data for consistent sleep research insights.   Multi-vendor datasets are increasingly common in sleep and circadian research, especially in large-scale or longitudinal studies. However, integrating outputs from different actigraph devices presents a significant methodological challenge. Variations in hardware, firmware, and proprietary algorithms can introduce inconsistencies that complicate cross-study comparisons. Data harmonization is therefore essential to ensure analytical validity and reproducibility. Why Multi-Vendor Variability Matters   Different actigraphy systems often use distinct sampling rates, sensitivity thresholds, and scoring algorithms to classify sleep and wake states. Even when devices appear functionally similar, these underlying differences can produce divergent estimates of total sleep time, sleep efficien...