Can an automated sleep detection algorithm for waist-worn accelerometry replace sleep logs?

2018 ◽  
Vol 43 (10) ◽  
pp. 1027-1032
Author(s):  
Tiago V. Barreira ◽  
Jessica G. Redmond ◽  
Tom D. Brutsaert ◽  
John M. Schuna ◽  
Emily F. Mire ◽  
...  

The purpose of this study was to test whether estimates of bedtime, wake time, and sleep period time (SPT) were comparable between an automated algorithm (ALG) applied to waist-worn accelerometry data and a sleep log (LOG) in an adult sample. A total of 104 participants were asked to log evening bedtime and morning wake time and wear an ActiGraph wGT3X-BT accelerometer at their waist for 24 h/day for 7 consecutive days. Mean difference and mean absolute difference (MAD) were computed. Pearson correlations and dependent-sample t tests were used to compare LOG-based and ALG-based sleep variables. Effect sizes were calculated for variables with significant mean differences. A total of 84 participants provided 2+ days of valid accelerometer and LOG data for a total of 368 days. There was no mean difference (p = 0.47) between LOG 472 ± 59 min and ALG SPT 475 ± 66 min (MAD = 31 ± 23 min, r = 0.81). There was no significant mean difference between bedtime (2348 h and 2353 h for LOG and ALG, respectively; p = 0.14, MAD = 25 ± 21 min, r = 0.92). However, there was a significant mean difference between LOG (0741 h) and ALG (0749 h) wake times (p = 0.01, d = 0.11, MAD = 24 ± 21 min, r = 0.92). The LOG and ALG data were highly correlated and relatively small differences were present. The significant mean difference in wake time might not be practically meaningful (Cohen’s d = 0.11), making the ALG useful for sample estimates. MAD, which gives a better estimate of the expected differences at the individual level, also demonstrated good evidence supporting ALG individual estimates.

Circulation ◽  
2013 ◽  
Vol 127 (suppl_12) ◽  
Author(s):  
Mary Cogswell ◽  
Chia-Yih Wang ◽  
Te-Ching Chen ◽  
Christine Pfeiffer ◽  
Paul Elliott ◽  
...  

Introduction: Reducing mean population sodium intake by ~1200 mg is projected to reduce thousands of deaths from heart disease and stroke and save billions of health care dollars annually. Twenty-four hour urine collection is recommended for assessing changes in mean population sodium intake, but can be difficult to implement. Predicting 24-hour urine sodium excretion using spot urines is not recommended due to diurnal variations in excretion. Further, sodium excretion patterns differ between black and white persons. We assessed the validity of previously published prediction equations for 24-hour sodium excretion in black and other young adults by timing of spot urine collection. Design: Of 481 adult volunteers aged 18-39 years (50% Blacks) asked to participate in a 2011 study in the Metropolitan DC area, 407 collected each urine void in a separate container for 24 hours. Four timed voids from the 24-h urine collection were selected (morning, afternoon, evening, and overnight) to use with previously published predictive equations. Predictive equations were based on one of two approaches; 1) an indirect approach using spot urine sodium-to-creatinine concentrations and predicted 24-hour creatinine excretion ( Tanaka, Kawasaki, Mage ), and 2) a direct approach using spot urine sodium, potassium, and creatinine concentrations, and age, and body mass index with separate equations by sex ( Brown ). We assessed mean differences between predicted and measured 24-hour sodium excretion (bias) and individual differences across levels of sodium excretion using Bland-Altman plots. Results: Among participants, mean measured 24-hour sodium excretion was ~3300 mg (SD ~1400 mg). Of the equations evaluated, mean bias in predicted 24-hour sodium excretion was least from Brown equations when using morning (-165 mg, 95% confidence interval [CI], -295, -36 mg), afternoon (-90 mg, 95% CI, -208, 28 mg) or evening ( -120 mg, 95% CI -230, -11 mg) spot urines. When using overnight spot urines, mean bias from Brown equations was greatest and statistically significant (-247 mg, 95% CI, -348, -151 mg). When using overnight spot urines, mean bias from Tanaka (-23 mg) or Mage (-145 mg) equations was not significant, however, when stratified by sex, mean biases were significant and in opposite directions. Among Blacks, mean biases from Brown were not significant (-167 to 122 mg) except using overnight specimens among Black females (-267 mg, 95% CI, -525, -47 mg). Across equations and time periods, Bland-Altman plots indicated significant bias at the individual level. Conclusions: Of the evaluated equations, predicted 24-hour urine sodium excretion using the Brown equations with morning, afternoon, or evening specimens may provide the least biased estimates of group mean sodium intake among young US adults. None of the equations adequately predicted individual 24-hour sodium excretion measured on the same day.


2019 ◽  
Vol 22 (17) ◽  
pp. 3140-3150 ◽  
Author(s):  
Valerie L Flax ◽  
Chrissie Thakwalakwa ◽  
Courtney H Schnefke ◽  
Heather Stobaugh ◽  
John C Phuka ◽  
...  

AbstractObjective:To validate digitally displayed photographic portion-size estimation aids (PSEA) against a weighed meal record and compare findings with an atlas of printed photographic PSEA and actual prepared-food PSEA in a low-income country.Design:Participants served themselves water and five prepared foods, which were weighed separately before the meal and again after the meal to measure any leftovers. Participants returned the following day and completed a meal recall. They estimated the quantities of foods consumed three times using the different PSEA in a randomized order.Setting:Two urban and two rural communities in southern Malawi.Participants:Women (n 300) aged 18–45 years, equally divided by urban/rural residence and years of education (≤4 years and ≥5 years).Results:Responses for digital and printed PSEA were highly correlated (>91 % agreement for all foods, Cohen’s κw = 0·78–0·93). Overall, at the individual level, digital and actual-food PSEA had a similar level of agreement with the weighed meal record. At the group level, the proportion of participants who estimated within 20 % of the weighed grams of food consumed ranged by type of food from 30 to 45 % for digital PSEA and 40–56 % for actual-food PSEA. Digital PSEA consistently underestimated grams and nutrients across foods, whereas actual-food PSEA provided a mix of under- and overestimates that balanced each other to produce accurate mean energy and nutrient intake estimates. Results did not differ by urban and rural location or participant education level.Conclusions:Digital PSEA require further testing in low-income settings to improve accuracy of estimations.


Circulation ◽  
2016 ◽  
Vol 133 (suppl_1) ◽  
Author(s):  
Thomas Eckstein ◽  
Laura Houghtaling ◽  
Mariah Quick

Traditionally, population behavioral characteristics are reported at the individual level. However, just like diseases, the combination of multiple adverse risk factors, even though they are often highly correlated, presents a different challenge and impact on community health than examining these same behaviors in isolation. We analyzed 5 risk factors in the 2014 Behavioral Risk Factor Surveillance Survey; smoking (currently a smoker), inactivity (no physical activity outside of work), excessive alcohol consumption (for women, 4 or more drinks in one sitting or an average of greater than one drink per day; for men, 5 or more drinks in one sitting or an average of greater than two drinks per day), obesity (BMI >=30), and insufficient sleep (< 7 hours per night). These five measures were selected because of their strong association with heart and other disease. We studied the frequency of multiple factors by state, sex, race, urbanicity, educational attainment and income. The attached map illustrates the variation among states in the prevalence of 3 or more risk factors in the population. In Utah, Colorado, and California, less than 9% of the population has 3 or more; in Arkansas, Louisiana, Kentucky and Mississippi, 16% or more of the population has 3 or more of these risk factors. Among demographic subpopulations, differences also exist. For non-Hispanic Asian population 4.5% (CI:3.5%-5.4%) have 3 or more risk factors compared to 16% or more exhibiting 3 or more risk factors in the non-Hispanic black, non-Hispanic American Indian and Alaskan Native, and non-Hispanic multi-racial populations. The variation among these subpopulations within states was also explored. Understanding the distribution of multiple adverse risk factors within a state’s population can help guide the efforts of public health officials, policy makers, advocacy groups and others to focus on the most affected populations and develop interventions that address multiple related conditions.


2014 ◽  
Vol 26 (8) ◽  
pp. 1301-1319 ◽  
Author(s):  
Andrea L. Rosso ◽  
Loni P. Tabb ◽  
Tony H. Grubesic ◽  
Jennifer A. Taylor ◽  
Yvonne L. Michael

Objective: Evaluate associations of neighborhood social capital and mobility of older adults. Method: A community-based survey (Philadelphia, 2010) assessed mobility (Life-Space Assessment [LSA]; range = 0-104) of older adults ( n = 675, census tracts = 256). Social capital was assessed for all adults interviewed from 2002-2010 ( n = 13,822, census tracts = 374). Generalized estimating equations adjusted for individual- and neighborhood-level characteristics estimated mean differences and 95% confidence intervals (CIs) in mobility by social capital tertiles. Interactions by self-rated health, living arrangement, and race were tested. Results: Social capital was not associated with mobility after adjustment for other neighborhood characteristics (mean difference for highest versus lowest tertile social capital = 0.79, 95% CI = [−3.3, 4.8]). We observed no significant interactions. In models stratified by race, Black participants had higher mobility in high social capital neighborhoods (mean difference = 7.4, CI = [1.0, 13.7]). Discussion: Social capital may not contribute as much as other neighborhood characteristics to mobility. Interactions between neighborhood and individual-level characteristics should be considered in research on mobility.


2021 ◽  
Vol 14 (5) ◽  
pp. 230
Author(s):  
Orie E. Barron ◽  
Charles R. Enis ◽  
Hong Qu

In this study, we study information processing by financial professionals benchmarked with non-professionals and how correlation among individual forecasts explains the group level forecast performance. In an experiment in which participants make price forecasts based on common financial information, we find that individual professionals are no better than individual non-professionals in forecasting, but professionals’ mean forecasts are superior. Our analysis suggests that financial professionals’ individual errors are less correlated as they process information from more diverse perspectives. This leads to superior mean forecasts because the uncorrelated individual errors cancel each other out in the aggregate. In contrast, non-professionals are similar in using salient information such as earnings or cash flow. As a result, their individual errors are highly correlated. Instead of cancelling each other out, the individual errors are enlarged in the aggregated mean forecasts. We are the first to show the difference in the comparisons of professionals and non-professionals at the group level versus at the individual level. Our paper contributes to the literature by documenting the evidence of diversity in information processing by financial professionals.


Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Mark Sanders ◽  
Paul Muntner ◽  
Rong Wei ◽  
Daichi Shimbo ◽  
Joseph E Schwartz ◽  
...  

Background: Prior studies have found a large difference between blood pressure (BP) when measured routinely in the clinic compared with research studies. We aimed to compare routine clinic BP to research-grade BP in a large, integrated health care system that has initiatives to standardize clinic BP measurements. Methods: We identified Kaiser Permanente Southern California members ≥ 65 years old diagnosed with hypertension and taking antihypertensive medication from the Ambulatory Blood Pressure in Older Adults (AMBROSIA) study. Research-grade BPs were obtained under standardized conditions by certified research staff using a semi-automatic oscillometric device, pre-programmed to take 3 measurements at 1-minute intervals. The average of the 3 BPs was used. The most recent (prior to study enrollment) routine clinic BP from an outpatient, non-urgent clinical care encounter, measured using a semi-automatic oscillometric device, was obtained via electronic health records. If there were multiple BP readings on the same day, the first reading was used. The mean difference between clinic BP and research-grade BP was tested using paired t-tests, while the Pearson correlation and a Bland-Altman analysis were used to assess level of agreement. Results: We included 309 participants (mean age 75 ± 6 years; 54% female; 49% non-Hispanic white, 17% non-Hispanic Black, 17% Hispanic, 15% Asian/Pacific Islander). When measured in routine clinic practice and in the research study, the mean (SD) systolic BP (SBP) was 135 (16) mm Hg and 132 (15) mm Hg, respectively, (mean difference = - 2.7 mm Hg; 95% CI -4.6 to -0.9; limits of agreement = -36 to 30 mm Hg) and the mean diastolic BP (DBP) was 70 (10) mm Hg and 69 (10) mm Hg, respectively (mean difference = - 0.9 mm Hg; 95% CI -2.1 to 0.3; limits of agreement = -22 to 20 mm Hg). Pearson correlation analysis showed modest correlations between the two types of BP measurements (SBP r=0.40, p<0.01; DBP r=0.45, p<0.01). Conclusion: The difference between clinic and research-grade BP was, on average, small, but differences at the individual level were often substantial.


Author(s):  
Sumin Lee ◽  
◽  
Wonho Jang ◽  

This research attempts to 1) explore trust from a theoretical angle using various perspectives in the social science research literature and 2) reveal the empirical relationship between trust and empathy at the individual level. Although trust and empathy share similar characteristics when considered in the realm of theory, they have typically been probed in distinct disciplines. Hence, there is a need for interdisciplinary perspective that addresses two concepts together. Using the Social Attitude Survey for Korean Society data collected in 2021, this study conducted a correlation and multivariate analysis that examined how much trust and empathy resemble. The results show that trust radius and interpersonal empathy are highly correlated. Also, trust and empathy levels differ from individual to individual in terms of one’s socioeconomic and demographic background. From this comparison, we emphasize the importance of the macro level effect of trust and empathy.


2020 ◽  
Vol 2 (4) ◽  
pp. 270-280
Author(s):  
Julian Matius Tagal

Purpose: To evaluate the repeatability and comparability of simulated K values obtained by the Galilei G4 Corneal Tomographer and the iDesign Wavefront Abberometer. Methods: The right eyes of 100 consecutive pre-laser-assisted in situ keratomileusis (LASIK) patients were included in this study. Patients with a history or signs of previous corneal or ocular trauma and infection were excluded. Paired corneal measurements for flat (K1) and steep (K2) meridians were obtained with both the Galilei and the iDesign. Repeatability was evaluated by calculating the coefficient of variation (CV) of the paired measurements. The comparability between platforms was evaluated by calculation of the mean differences followed by the construction of Bland-Altman plots and calculation of limits of agreement (LOA). Results: While the mean CV for both devices was low (0.17% versus 0.57% for the Galilei and iDesign, respectively), a large proportion of eyes measured by the iDesign (22%) showed an absolute difference of > 0.5 D between paired readings, compared to 1% as measured by the Galilei. The Galilei consistently measured higher than the iDesign. Although the mean difference did not exceed 0.17 D, the LOAs were unacceptablywide at -0.52 D to 0.85 D and -0.69 D to 0.89 D for K1 and K2, respectively. Conclusion: As regards keratometry, the iDesign demonstrated clinically unacceptable repeatability. Both platforms demonstrated sufficiently wide LOA that we could not recommend that they are used interchangeably.


2014 ◽  
Vol 281 (1795) ◽  
pp. 20141385 ◽  
Author(s):  
Gregory P. Brown ◽  
Benjamin L. Phillips ◽  
Richard Shine

At the edge of a biological invasion, evolutionary processes (spatial sorting, natural selection) often drive increases in dispersal. Although numerous traits influence an individual's displacement (e.g. speed, stamina), one of the most important is path straightness. A straight (i.e. highly correlated) path strongly enhances overall dispersal rate relative to time and energetic cost. Thus, we predict that, if path straightness has a genetic basis, organisms in the invasion vanguard will exhibit straighter paths than those following behind. Our studies on invasive cane toads ( Rhinella marina ) in tropical Australia clearly support this prediction. Radio-tracking of field-collected toads at a single site showed that path straightness steadily decreased over the first 10 years post-invasion. Consistent with an evolved (genetic) basis to that behavioural shift, path straightness of toads reared under common garden conditions varied according to the location of their parents' origin. Offspring produced by toads from the invasion vanguard followed straighter paths than did those produced by parents from long-established populations. At the individual level, offspring exhibited similar path straightness to their parents. The dramatic acceleration of the cane toad invasion through tropical Australia has been driven, in part, by the evolution of a behavioural tendency towards dispersing in a straight line.


2019 ◽  
Vol 76 (11) ◽  
pp. 2080-2088 ◽  
Author(s):  
Suzanne J. Kelson ◽  
Michael R. Miller ◽  
Tasha Q. Thompson ◽  
Sean M. O’Rourke ◽  
Stephanie M. Carlson

Partial migration is a common phenomenon wherein populations include migratory and resident individuals. Whether an individual migrates or not has important ecological and management implications, particularly within protected populations. Within partially migratory populations of Oncorhynchus mykiss, migration is highly correlated with a specific genomic region, but it is unclear how well this region predicts migration at the individual level. Here, we relate sex and life history genotype, determined using >400 single nucleotide polymorphisms (SNPs) on the migratory-linked genomic region, to life history expression of marked juvenile O. mykiss from two tributaries to the South Fork Eel River, northern California. Most resident fish were resident genotypes (57% resident, 37% heterozygous, 6% migratory genotype) and male (78%). Most migratory fish were female (62%), but were a mixture of genotypes (30% resident, 45% heterozygous, 25% migratory genotype). Sex was more strongly correlated with life history expression than genotype, but the best-supported model included both. Resident genotypes regularly migrated, highlighting the importance of conserving the full suite of life history and genetic diversity in partially migratory populations.


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