From:  Evaluation of a digital fully-contactless optical device to quantify and record breathing pattern components at rest and after exercise

 Mean differences between the comparable methods at rest, after exercise, and for breath-by-breath analysis

VariableAt restAfter exerciseBreath-by-breath analysis
μ (SD)95% LOA (lower, upper)μ (SD)95% LOA (lower, upper)μ (SD)95% LOA (lower, upper)
RR (bpm)0.01* (0.04)–0.07, 0.090.01 (0.02)–0.03, 0.05--
Te (s)–0.03 (0.09)–0.21, 0.150.01 (0.04)–0.07, 0.090.00 (0.30)–0.58, 0.58
Ti/Ttot0.00 (0.02)–0.37, 0.370.00 (0.01)–0.02, 0.020.00 (0.04)–0.08, 0.08
Rcampi (arbitrary units)**0.31 (0.18)–0.06, 0.660.44 (0.29)–0.13, 1.010.43 (0.31)–0.19, 1.05
ABampi (arbitrary units)**0.23 (0.15)–0.06, 0.520.29 (0.20)–0.10, 0.680.28 (0.21)–0.13, 0.69
RCampi/ABampi0.03 (0.21)–0.33, 0.441.10 (0.24)–0.38, 0.580.12 (0.69)–1.23, 1.47

* In some cases, at the end of the aligned sum signal from either the SLP or RIP, a half or full breath cycle was identified. This occurred because the algorithm continued to detect respiratory activity until each device was manually stopped. As a result, the mean differences for this variable include decimal values. ** Arbitrary units were estimated due to a lack of a previously validated weighting factor for calibrating the SLP and due to the different recording approaches of the devices to measure chest wall displacement. -: no data. 95% LOA: 95% limits of agreement; ABampi: abdominal amplitude; bpm: breaths per minute; RCampi: ribcage amplitude; RIP: respiratory inductive plethysmography; RR: respiratory rate (expressed by bpm and the breath-by-breath analysis involved breath cycles during the whole recording period); SD: standard deviation; SLP: structured light plethysmography; Te: expiratory time; Ti: inspiratory time; Ttot: total breath cycle duration; μ: mean value