Category: Statistics

Arch Argent Pediatr. 2021 Oct;119(5):325-330. doi: 10.5546/aap.2021.eng.325.

ABSTRACT

INTRODUCTION: Infections due to bacteremia in burn patients are a common cause of complications and an extended length of stay. Knowing causative microorganisms and identifying associated risk factors allow to reduce infectious complications, morbidity, mortality, and health care expenditure. This study assesses the extent of the association between risk factors and bacteremia in burn patients and identifies the most common microorganisms found in blood cultures.

POPULATION AND METHODS: Case-control study conducted at the Burn Intensive Care Unit of Hospital de Pediatría S.A.M.I.C. “Prof. Dr. Juan P. Garrahan” between June 1st, 2014 and September 30th, 2019 in patients with bacteremia events and a positive blood culture (cases) and patients with a negative blood culture (controls).

RESULTS: During the study period, 29 cases of bacteremia were identified. The median length of stay at the time of bacteremia was 23 days. The most commonly identified microorganism was Pseudomonas (7 cases). The only risk factor that showed a significant association was the presence of a central venous line for 7 days or more (OR: 3.18; 95 % confidence interval: 1.20- 8.38). The overall mortality rate was 9.1%; 13.8% for cases and 3.4% for controls.

CONCLUSIONS: Central venous lines for more than 7 days are an independent risk factor for bacteremia in critically ill burn children. No statistically significant association was established with other studied risk factors. Pseudomonas, Acinetobacter, and coagulase-negative Staphylococcus were the most common microorganisms found in bacteremia.

PMID:34569740 | DOI:10.5546/aap.2021.eng.325

Arch Argent Pediatr. 2021 Oct;119(5):e435-e440. doi: 10.5546/aap.2021.eng.e435.

ABSTRACT

INTRODUCTION: Hospital readmissions in pediatrics are a severe, potentially avoidable problem of health systems. In our setting, there is little information about this topic.

OBJECTIVE: To estimate the rate of readmissions, the proportion of potentially preventable readmissions, and their associated characteristics.

MATERIAL AND METHODS: Cross-sectional study including hospital readmissions of patients aged 0-18 years, admitted to a tertiary care children’s hospital between January 1st and December 31st, 2018. Readmissions were assessed as potentially preventable based on whether they were or not related to the previous admission.

RESULTS: Out of 8228 hospital admissions recorded in the study period, the rate of readmissions for any cause was 10 % at 30 days and 7.1 % at 15 days. The proportion of readmissions classified as potentially preventable was 47.9 % at 30 days and 47.5 % at 15 days. No statistically significant differences were observed between readmissions at 30 and 15 days in terms of patient age, health insurance, presence of chronic disease or cause of readmission.

CONCLUSION: The rate of hospital readmissions was 10 % at 30 days and 7.1 % at 15 days of discharge; almost half of them were considered potentially preventable.

PMID:34569745 | DOI:10.5546/aap.2021.eng.e435

J Int AIDS Soc. 2021 Sep;24(9):e25815. doi: 10.1002/jia2.25815.

ABSTRACT

INTRODUCTION: In sub-Saharan Africa, less than half of young people know their HIV status. HIV self-testing (HIVST) is a testing strategy with the potential to offer privacy and autonomy. We aimed to understand the uptake and acceptability of different HIV testing options for youth in Harare, Zimbabwe.

METHODS: This study was nested within a cluster randomized trial of a youth-friendly community-based integrated HIV and sexual and reproductive health intervention for youth aged 16-24 years. Three HIV testing options were offered: (1) provider-delivered testing; (2) HIVST on site in a private booth without a provider present; and (3) provision of a test kit to test off site. Descriptive statistics and proportions were used to investigate the uptake of HIV testing in a client sample. A focus group discussion (FGD) with intervention providers alongside in-depth interviews, paired interviews and FGDs with a selected sample of youth clients explored uptake and acceptability of the different HIV testing strategies. Thematic analysis was used to analyse the qualitative data.

RESULTS: Between April and June 2019, 951 eligible clients were tested for HIV: 898 (94.4%) chose option 1, 30 (3.25%) chose option 2 and 23 (2.4%) chose option 3. Option 1 clients cited their trust in the service and a desire for immediate counselling, support and guidance from trusted providers as the reasons for their choice. Young people were not confident in their expertise to conduct HIVST. Concerns about limited privacy, confidentiality and lack of support in the event of an HIV-positive result were barriers for off-site HIVST.

CONCLUSIONS: In the context of supportive, trusted and youth-friendly providers, youth clients overwhelmingly preferred provider-delivered HIV testing over client-initiated HIVST or HIVST off site. This highlights the importance of listening to youth to improve engagement in testing. While young people want autonomy in choosing when, where and how to test, they do not want to necessarily test on their own. They desire quality in-person counselling, guidance and support, alongside privacy and confidentiality. To increase the appeal of HIVST for youth, greater provision of access to private spaces is required, and accessible pre- and post-test counselling and support may improve uptake.

PMID:34569710 | DOI:10.1002/jia2.25815

Catheter Cardiovasc Interv. 2021 Sep 27. doi: 10.1002/ccd.29961. Online ahead of print.

ABSTRACT

OBJECTIVES: To develop a model to predict risk of in-hospital bleeding following endovascular peripheral vascular intervention.

BACKGROUND: Peri-procedural bleeding is a common, potentially preventable complication of catheter-based peripheral vascular procedures and is associated with increased mortality. We used the National Cardiovascular Data Registry (NCDR) Peripheral Vascular Interventions (PVI) Registry to develop a novel risk-prediction model to identify patients who may derive the greatest benefit from application of strategies to prevent bleeding.

METHODS: We examined all patients undergoing lower extremity PVI at 76 NCDR PVI hospitals from 2014 to 2017. Patients with acute limb ischemia (n = 1600) were excluded. Major bleeding was defined as overt bleeding with a hemoglobin (Hb) drop of ≥ 3 g/dl, any Hb decline of ≥ 4 g/dl, or a blood transfusion in patients with pre-procedure Hb ≥ 8 g/dl. Hierarchical multivariable logistic regression was used to develop a risk model to predict major bleeding. Model validation was performed using 1000 bootstrapped replicates of the population after sampling with replacement.

RESULTS: Among 25,382 eligible patients, 1017 (4.0%) developed major bleeding. Predictors of bleeding included age, female sex, critical limb ischemia, non-femoral access, prior heart failure, and pre-procedure hemoglobin. The model demonstrated good discrimination (optimism corrected c-statistic = 0.67), calibration (corrected slope = 0.98, intercept of -0.04) and range of predicted risk (1%-18%).

CONCLUSIONS: Post-procedural PVI bleeding risk can be predicted based upon pre- and peri-procedural patient characteristics. Further studies are needed to determine whether this model can be utilized to improve procedural safety through developing and targeting bleeding avoidance strategies.

PMID:34569709 | DOI:10.1002/ccd.29961

Alzheimers Dement. 2021 Sep 27. doi: 10.1002/alz.12469. Online ahead of print.

ABSTRACT

INTRODUCTION: The determinants of the secular decline in the incidence of dementia are not clear. The aim of this study was to investigate the influences of four factors-education, wealth, cerebrovascular health, and general health-on the secular decline.

METHODS: A cohort study was conducted of all individuals aged ≥65 years in Denmark from 2005 through 2018 (N = 1,757,168). Annual incidence rates of dementia and population attributable risks of the four factors were calculated and birth cohort trends were examined.

RESULTS: The incidence of dementia declined by 22.5% in men and 34.2% in women from 2005 through 2018. Population attributable risks of lower education, lower wealth, and stroke likewise declined. Independent of these improvements, the incidence of dementia fell across successive birth cohorts.

DISCUSSION: Most of the observed plasticity in late-onset dementia is associated with a risk decline across successive birth cohorts that is independent of improvements in traditional risk factors.

PMID:34569688 | DOI:10.1002/alz.12469

Orthod Craniofac Res. 2021 Sep 27. doi: 10.1111/ocr.12537. Online ahead of print.

ABSTRACT

OBJECTIVE: Aim of this study was to compare the mechanical properties of orthodontic aligners among different commercially available 3D printing devices.

MATERIALS AND METHODS: Five 3D printers (Ka:rv LP 550, Swinwon; “KAR”), (L120, Dazz 3D; “L12”), (MiiCraft 125, Miicraft Jena; “MIC”), (Slash 2, Uniz; “SLS”) and (Pro 95, SprintRay; “PRO”) were used to prepare orthodontic aligners with dental resin (Tera Harz TC-85DAW, Graphy). The central incisors of each aligner were cut, prepared, and evaluated in terms of Martens-Hardness (HM), indentation-modulus (E_IT ), and elastic-index (η_IT ) as per ISO14577-1:2002. Force-indentation curves were recorded and differences among printers were checked with generalized linear regressions (alpha=5%).

RESULTS: Statistically significant differences were seen for all mechanical properties (P<0.05), which were in descending order: HM (N/mm² ) as median (Interquartile Range [IQR]): SLS 108.5 (106.0-112.0), L12 103.0 (102.0-107.0), KAR 101.5 (97.5-103.0), MIC 100.0 (97.5-101.5), and PRO 94.0 (93.0-96.0); E_IT (MPa) as mean (Standard Deviation [SD]): SLS 2696.3 (124.7), L12 2627.8 (73.5), MIC 2566.2 (125.1), KAR 2565.0 (130.2), PRO 2491.2 (53.3); η_IT (%) as median (IQR): SLS 32.8 (32.3-33.1), L12 31.6 (30.8-32.3), KAR 31.3 (30.9-31.9), MIC 30.5 (29.9-31.2), PRO 29.5 (29.1-30.0). Additionally, significant differences existed between Liquid Crystal Display (LCD) and Digital Light Processing (DLP) printers for HM (P<0.001), E_IT (P=0.002), and η_IT (P<0.001), with aligners from the former having higher values than aligners from the latter printer.

CONCLUSION: Under the limitations of this study it may be concluded that the mechanical properties of 3D-printed orthodontic aligners are dependent on the 3D printer used and thus differences in their clinical efficacy are anticipated.

PMID:34569692 | DOI:10.1111/ocr.12537

Int J Geriatr Psychiatry. 2021 Sep 27. doi: 10.1002/gps.5624. Online ahead of print.

ABSTRACT

OBJECTIVES: Cognitive training exercises (CTE) are promising and effective interventions to enhance cognitive reserve and slowdown cognitive deterioration in people with subjective memory impairment (SCI) and mild cognitive impairment (MCI). In this pilot study, we aimed to assess the feasibility of CTE among Egyptian adults.

METHODS: Eighteen participants above forty years-old were recruited. They underwent baseline neuropsychological assessment and functional assessment. However, after receiving a 6 weeks’ cognitive training, eight participants (seven with MCI and one was cognitively intact) dropped out from the study. Finally, ten participants (eight participants with MCI, one with SCI and one was cognitively intact) completed twelve weeks of CTE and undergone the post assessment afterwards. CTE included visual, verbal, memory, executive function, visuospatial, attention and psychokinetic exercises through onsite and home-based sessions RESULTS: For the ten participants who completed twelve weeks of CTE, the Wilcoxon signed-rank test showed a statistically significant change in the scores of MMSE (Z= -2.546, p=.011), semantic fluency test (Z= -2.913, p=.004), SMCQ (Z= -2.913, p=.004), CERAD Word List (1st trial: Z = -2.641, p=.008;Word list recall: Z= -2.825, p=.005), construction abilities (immediate: Z= -2.121, p=.034; delayed recall: Z= -2.414, p=.016), and Digit span test (forward: Z= -2.724, p=.006; backward: Z= -2.724, p=.006).

CONCLUSIONS: The results of this study suggested that CTE are feasible among Egyptian adults, especially those with MCI, and potentially effective in enhancing global cognition and after twelve weeks of training. Future research should shed light on the efficacy of longitudinal CTE implementation in Arab adults’ populations. This article is protected by copyright. All rights reserved.

PMID:34569644 | DOI:10.1002/gps.5624

J Clin Lab Anal. 2021 Sep 27:e24025. doi: 10.1002/jcla.24025. Online ahead of print.

ABSTRACT

OBJECTIVES: To identify the SPINK1 or SPINK1-based model as a more reliable biomarker for the diagnosis of hepatocellular carcinoma (HCC).

METHODS: Serum samples and related laboratory parameters were collected from 540 subjects (119 healthy donors, 113 patients with chronic hepatitis B, 122 patients with liver cirrhosis, and 186 patients with HCC). SPINK1 was determined by ELISA assay. Differences in each variable were compared by one-way ANOVA or Kruskal-Wallis test. ROC (receiver operating characteristic) curve analysis was conducted to compare the diagnostic efficiency of alpha-fetoprotein (AFP), SPINK1, and a SPINK1-based combine model constructed by binary Logistic regression.

RESULTS: In detecting HCC using the other three groups as control, ROC curve analysis revealed that SPINK1 alone reached AUC of 0.899 (0.866-0.933), with the sensitivity of 0.812 of and specificity of 0.953. The combined model increased the AUC to 0.945 (0.926-0.964) with the sensitivity and specificity of 0.860 and 0.910, respectively. For AFP, significantly lower AUC (p < 0.0001) was shown, which was 0.695 (0.645-0.745) with the sensitivity and specificity of 0.634 and 0.718, respectively. In discriminating HCC from liver disease control, AUC of SPINK1 was 0.863(0.826-0.894), the sensitivity and specificity were 0.823 and 0.906, respectively. For combined model, the AUC, sensitivity, and specificity were 0.915 (0.884-0.940), 0.863, and 0.916, respectively. For detecting early-stage HCC, SPINK1 and combined model achieved the sensitivity of 0.788 and 0.818, respectively, much higher than AFP of 0.485 (p < 0.05); however, the difference between SPINK1 and combined model was not statistically significant (p = 1).

CONCLUSION: We provided solid evidence for SPINK1 as a robust serological tool for HCC diagnosis.

PMID:34569662 | DOI:10.1002/jcla.24025

Phys Chem Chem Phys. 2021 Sep 27. doi: 10.1039/d1cp03116c. Online ahead of print.

ABSTRACT

The energy dependence of the rates of the reactions between He⁺ and ammonia (NY₃, Y = {H,D}), forming NY₂⁺, Y and He as well as NY⁺, Y₂ and He, and the corresponding product branching ratios have been measured at low collision energies E_coll between 0 and k_B·40 K using a recently developed merged-beam technique [Allmendinger et al., ChemPhysChem, 2016, 17, 3596]. To avoid heating of the ions by stray electric fields, the reactions are observed within the large orbit of a highly excited Rydberg electron. A beam of He Rydberg atoms was merged with a supersonic beam of ammonia using a curved surface-electrode Rydberg-Stark deflector, which is also used for adjusting the final velocity of the He Rydberg atoms, and thus the collision energy. A collision-energy resolution of about 200 mK was reached at the lowest E_coll values. The reaction rate coefficients exhibit a sharp increase at collision energies below ∼k_B·5 K and pronounced deviations from Langevin-capture behaviour. The experimental results are interpreted in terms of an adiabatic capture model describing the rotational-state-dependent orientation of the ammonia molecules by the electric field of the He⁺ atom. The model faithfully describes the experimental observations and enables the identification of three classes of |JKMp〉 rotational states of the ammonia molecules showing different low-energy capture behaviour: (A) high-field-seeking states with |KM| ≥ 1 correlating to the lower component of the umbrella-motion tunnelling doublet at low fields. These states undergo a negative linear Stark shift, which leads to strongly enhanced rate coefficients; (B) high-field-seeking states subject to a quadratic Stark shift at low fields and which exhibit only weak rate enhancements; and (C) low-field-seeking states with |KM| ≥ 1. These states exhibit a positive Stark shift at low fields, which completely suppresses the reactions at low collision energies. Marked differences in the low-energy reactivity of NH₃ and ND₃-the rate enhancements in ND₃ are more pronounced than in NH₃-are quantitatively explained by the model. They result from the reduced magnitudes of the tunnelling splitting and rotational intervals in ND₃ and the different occupations of the rotational levels in the supersonic beam caused by the different nuclear-spin statistical weights. Thermal capture rate constants are derived from the model for the temperature range between 0 and 10 K relevant for astrochemistry. Comparison of the calculated thermal capture rate coefficients with the absolute reaction rates measured above 27 K by Marquette et al. (Chem. Phys. Lett., 1985, 122, 431) suggests that only 40% of the close collisions are reactive.

PMID:34569565 | DOI:10.1039/d1cp03116c

Phys Chem Chem Phys. 2021 Sep 27. doi: 10.1039/d1cp00783a. Online ahead of print.

ABSTRACT

This paper offers an expedient, efficient, and unique treatment of multimode quantum subsystems (polyatomic molecules) interacting with a classical environment in which the time evolution of the coupling term is governed by the algebraic rules of statistical mechanics in mixed quantum-classical systems developed by Kapral and Nielsen [S. Nielsen, R. Kapral, and G. Ciccotti, J. Chem. Phys., 2001, 115, 5805]. This unique time evolution of the coupling term is neither quantal nor classical but rather something different that relies heavily on Wigner transform, thereby leading to non-Newtonian mechanics. As such, an argument is presented that the approach provided herein for treating polyatomic molecular systems in a mixed quantum-classical environment is new and different as opposed to the many other schemes of semiclassical dynamics that are normally employed to study such systems. The merits of expediency and efficiency of the herein mixed quantum-classical dynamics calculations emanate from avoiding using integrals for time evolutions, and, instead, employing matrix mechanics whereby LU decomposition and singular value decomposition (SVD) numerical techniques are utilized for diagonalization. An electronic 2-level subsystem interacting with a classical bath through the spin-boson model to render accurate pure electronic dephasing in multimode molecular systems by eliminating the unphysical asymmetry in the line shape of the zero-phonon line (ZPL) exhibited by other models is exploited. This work has a superior advantage over the single-mode spin-boson model, published previously, whereby a multitude of types of vibrational modes (slow, fast, or both) of the quantum subsystem may readily be handled using different spectral densities. The spin-boson model used here is a composite system made up of a quantum subsystem, i.e., a subsystem bilinearly coupled to a multidimensional harmonic oscillator (representing the intermediate quantum vibrational modes between the electronic subsystem and the bath), interacting with a classical bath, where the coupling term is governed by the mixed quantum-classical Liouville equation. A multidimensional coherent-state approach is employed to deal with the time evolution of the quantum subsystem. A closed-form expression of linear and nonlinear optical electronic transition dipole moment time correlation functions in mixed quantum-classical dissipative media is derived. Pure electronic dephasing is probed using the aforementioned approach. Linear absorption spectra and 4-wave mixing signals (e.g., photon echo and pump-probe) are calculated showing a reasonable thermal broadening, temporal decay, and accurate pure dephasing.

PMID:34569571 | DOI:10.1039/d1cp00783a