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Summary: Point‐of‐care haemoglobin measurement devices may play an important role in the antenatal detection of anaemia in pregnant people and may be useful in guiding blood transfusion during resuscitation in obstetric haemorrhage. We compared baseline haemoglobin variability of venous and capillary HemoCue® haemoglobin, and Masimo® Rad‐67 Pulse CO‐Oximeter haemoglobin with laboratory haemoglobin in people on the day of their planned vaginal birth. A total of 180 people undergoing planned vaginal birth were enrolled in this prospective observational study. Laboratory haemoglobin was compared with HemoCue and Masimo Rad‐67 Pulse CO‐Oximeter measurements using Bland–Altman analysis, calculating mean difference (bias) and limits of agreement. Five (2.8%) people had anaemia (haemoglobin < 110 g.l‐1). Laboratory haemoglobin and HemoCue venous haemoglobin comparison showed an acceptable bias (SD) 0.7 (7.54) g.l‐1 (95%CI ‐0.43–1.79), with limits of agreement ‐14.10–15.46 g.l‐1 and acceptable agreement range of 29.6 g.l‐1. Laboratory and HemoCue capillary haemoglobin comparison showed an unacceptable bias (SD) 13.3 (14.12) g.l‐1 (95%CI 11.17–15.34), with limits of agreement ‐ 14.42–40.93 g.l‐1 and unacceptable agreement range of 55.3 g.l‐1. Laboratory and Masimo haemoglobin comparison showed an unacceptable bias (SD) ‐14.0 (11.15) g.l‐1 (95%CI ‐15.63 to ‐12.34), with limits of agreement to ‐35.85 to 7.87 g.l‐1 and acceptable agreement range of 43.7 g.l−1. Venous HemoCue, with its acceptable bias and limits of agreement, should be applied more widely in the antenatal setting to detect, manage and risk stratify pregnant people with anaemia. HemoCue capillary measurement under‐estimated haemoglobin and Masimo haemoglobin measurement over‐estimated, limiting their clinical use. Serial studies are needed to determine if the accuracy of venous HemoCue haemoglobin measurement is sustained in other obstetric settings. [ABSTRACT FROM AUTHOR]

Objective . Transcranial electrical stimulation (tES) is a promising method for modulating brain activity and excitability with variable results to date. To minimize electric (E-)field strength variability, we introduce the 2-sample prospective E-field dosing (2-SPED) approach, which uses E-field strengths induced by tES in a first population to individualize stimulation intensity in a second population. Approach . We performed E-field modeling of three common tES montages in 300 healthy younger adults. First, permutation analyses identified the sample size required to obtain a stable group average E-field in the primary motor cortex (M1), with stability being defined as the number of participants where all group-average E-field strengths ± standard deviation did not leave the population's 5-95 percentile range. Second, this stable group average was used to individualize tES intensity in a second independent population (n = 100). The impact of individualized versus fixed intensity tES on E-field strength variability was analyzed. Main results . In the first population, stable group average E-field strengths (V/m) in M1 were achieved at 74-85 participants, depending on the tES montage. Individualizing the stimulation intensity (mA) in the second population resulted in uniform M1 E-field strength (all p < 0.001) and significantly diminished peak cortical E-field strength variability (all p < 0.01), across all montages. Significance . 2-SPED is a feasible way to prospectively induce more uniform E-field strengths in a region of interest. Future studies might apply 2-SPED to investigate whether decreased E-field strength variability also results in decreased physiological and behavioral variability in response to tES., (Creative Commons Attribution license.)