Digital Anthropometry: A Systematic Review on Precision, Reliability and Accuracy of Most Popular Existing Technologies.

Digital anthropometry (DA) has been recently developed for body composition evaluation and for postural analysis. The aims of this review are to examine the current state of DA technology, as well as to verify the methods for identifying the best technology to be used in the field of DA by evaluating the reliability and accuracy of the available technologies on the market, and lay the groundwork for future technological developments. A literature search was performed and 28 studies met the inclusion criteria. The reliability and accuracy of DA was high in most studies, especially in the assessment of patients with obesity, although they varied according to the technology used; a good correlation was found between DA and conventional anthropometry (CA) and body composition estimates. DA is less time-consuming and less expensive and could be used as a screening tool before more expensive imaging techniques or as an alternative to other less affordable techniques. At present, DA could be useful in clinical practice, but the heterogeneity of the available studies (different devices used, laser technologies, population examined, etc.) necessitates caution in the interpretation of the obtained results. Furthermore, the need to develop integrated technologies for analyzing body composition according to multi-compartmental models is increasingly evident.

Variable selection and importance in presence of high collinearity: an application to the prediction of lean body mass from multi-frequency bioelectrical impedance.

In prediction problems both response and covariates may have high correlation with a second group of influential regressors, that can be considered as background variables. An important challenge is to perform variable selection and importance assessment among the covariates in the presence of these variables. A clinical example is the prediction of the lean body mass (response) from bioimpedance (covariates), where anthropometric measures play the role of background variables. We introduce a reduced dataset in which the variables are defined as the residuals with respect to the background, and perform variable selection and importance assessment both in linear and random forest models. Using a clinical dataset of multi-frequency bioimpedance, we show the effectiveness of this method to select the most relevant predictors of the lean body mass beyond anthropometry.

Factor structure and psychometric properties of the Italian version of the Gambling Related Cognitions Scale (GRCS-I).

The past decade has witnessed an expanded accessibility and popularity of gambling worldwide, and in Italy the phenomenon significantly increased. Nevertheless, little is known about the role of gambling cognitions among Italian individuals, and few scales assessing problem gambling have been validated. The purpose of the present study was to examine and validate the Gambling Related Cognitions Scale-Italian version (GRCS-I), based on the 23-item Gambling Related Cognitions Scale (GRCS). Two-tailed t tests, ANOVA, MANOVA, Pearson's correlation, and multiple regression analyses were used for continuous variables, while χ(2) tests with Yates's correction for categorical variables. Cronbach's α was utilized to determine the internal consistency, and logistic regression analysis and the receiver operating characteristic curve analysis to determine discriminant validity. Principal axis factoring with Oblimin rotation was applied, and then confirmatory factor analysis was used to cross-validate the factor structures. We extracted a five-factor solution that accounted for 60 % of variance. All 23 items had communalities and factor loadings were satisfactory, and the factor structures were similar to the original version of the measure. The Cronbach's α coefficients were adequate, and concurrent and discriminant validities of the GRCS were also confirmed. GRCS-I presented good psychometric properties and it demonstrated good validity and reliability, providing a valid and suitable tool for the assessment of gambling related cognitions among Italian individuals.

Progressive loss in circulating volume during haemodialysis can be monitored by time voltage integral area of QRS complex: pilot study.

INTRODUCTION: Time voltage area of QRS is a parameter that showed a close association with modifications in endoventricular volume. The aim of the study was to investigate the efficacy of this parameter in identifying progressive reduction in circulating blood volume (BV) during haemodialytic treatment (HT). MATERIAL AND METHODS: Thirteen uraemic patients were studied. XYX like leads were monitored before, during and after HT. Summation of areas of each QRS complex was named QRS total area (TA). RESULTS: Increase in QRS TA and decrease in BV were found after vs. before HT. Progressive increase in QRS TA is strongly linked to a progressive reduction of BV during HT. CONCLUSIONS: THESE FINDINGS ENCOURAGE USE OF ECG MONITORING DURING HT WITH A DUAL PURPOSE: rhythm and haemodynamic control. In fact, excessive or insufficient subtractions of water, with consequent hypotensive or cardiorespiratory crisis, are the most frequent complications in these patients.

Parathyroidectomy eliminates arrhythmic risk in primary hyperparathyroidism, as evaluated by exercise test.

OBJECTIVE: To investigate whether parathyroidectomy (PTx) reverses risk factors for arrhythmias related to the QT dynamic changes evaluated during bicycle ergometry exercise test (ET). METHODS: Twenty-four postmenopausal women with primary hyperparathyroidism (PHPT) (mean age 60.08.4 years) and 30 sex- and age-matched controls underwent ET, echocardiography, and biochemical evaluation. The following stages were considered during ET: rest, peak exercise, and recovery. The patients were randomized to two groups: 12 underwent PTx (group A) and 12 were followed-up conservatively (group B). After 6 months, the patients were studied again. RESULTS: Groups A and B showed no differences in mean baseline biochemical values, echocardiographic parameters, and QTC interval. PHPT patients showed an increased occurrence of ventricular premature beats (VPBS) during ET compared with controls (37.0 vs 6.6%, P=0.03). Serum calcium level was a predictor of VPBS (P=0.05). Mean value of QTC was in the normal range at baseline (Group A: 401±16.9; group B: 402.25±13.5 ms) but significantly lower than controls (417.8±25.1 ms, P<0.01). A negative correlation was found between QTc and calcium values (P=0.03). Physiological reduction of QTc interval from rest to peak exercise was not observed in PHPT patients before surgery. After PTx, group A had a significant reduction in VPBs compared with baseline (at baseline, 5 of 12 vs none of 12 patients after PTx, P=0.03) and a restored normal QT adaptation during ET. Group B showed no significant changes after a 6-month period. CONCLUSIONS: PTx reduces the occurrence of VPBs and restored the QTc adaptation during ET.

Analysis of extrema of heartbeat time series in exercise test.

The heartbeat time series of the electrocardiogram recorded during exercise test clearly reflects the physiological control mechanism of the autonomic nervous system on heart rate. This series shows both decreasing and increasing trends and variability of the variance. We analyse the series of intervals between two consecutive extrema, i.e. the durations of accelerations or decelerations of heart rate. We compute the distribution of the length of these intervals and their mean in a model of stationary independent variables, where they are independent of the variables' distribution. We use the mean length as discriminant statistics to compare stress and recovery phases. Data analysis performed over the heartbeat series of 14 healthy subjects shows significant difference between stress and recovery.

The loss of entropy circadian rhythm in sinusal R-R intervals of type 1 diabetic pregnant women suggests an indeterministic chaos in cardiac pacing (minimum delirium cordis syndrome). A newly identifiable type of silent cardiac dysautonomia?

OBJECTIVE: The scope of this study is to detect whether or not the entropy (E) circadian rhythm (CR) is maintained preserved in sinusal R-R intervals (SRRI), its loss being the expression of a transition to an indeterministic chaos in heart rate variability (HRV). METHODS: The E of SRRI was estimated in 14 type I diabetic pregnant women (DPW) in the first trimester of an apparently uncomplicated gestation (7 patients - mean age = 30.3 +/- 4.1 y - without clinical and laboratory evidence of cardiac autonomic neuropathy, and 7 patients - mean age = 30.7 +/- 3.6 y - with positive tests for a cardiac dysautonomia). The E CR was studied via the single cosinor method, and summarized via the population-mean cosinor method. RESULTS: The E CR was found not to be preserved in both the investigated type I DPW, despite the occurrence of the SRRI CR. CONCLUSIONS: The loss of the E CR confirms that in type I DPW there is a transition to an indeterministic disorder in HRV due to the lack of an autocorrelated periodic chaos in cardiac pacing. Such an unphysiological neurovegetative regulation suggests a new silent cardiac dysautonomic syndrome, that we intend to call "minimum delirium cordis syndrome" (MDCS). Can the MDCS be regarded as a condition of cardiovascular risk? To answer this question, it seems justified to suggest that the study of the E CR should be added to the routine tests that are presently applied to clinical analysis of the Holter ECG, being the classic tests of linear analysis not methodologically suitable for detecting the indeterministic chaos of the MDCS.

Spectral and symbolic analysis of heart rate data during the tilt test.

Spectral analysis of heart rate sequences is commonly used to investigate neuroauthonomic control of heart rate by means of two indexes, the low and the high frequency power. For tilt test data of normal subjects we compare the spectral indexes with new indexes defined within the framework of symbolic analysis. We define two classes of binary words of length 4: the first class is related to "acceleration" of heart rate and the second class to "stationary behavior." The new indexes measure the change in frequency of the two classes before and after the tilt. Data analysis of 13 normal subjects shows that the behavior of the new indexes is in agreement with that of spectral ones.