Category: Statistics

Respiration. 2021 Apr 13:1-9. doi: 10.1159/000515335. Online ahead of print.

ABSTRACT

BACKGROUND: In idiopathic pulmonary fibrosis (IPF), some physiological parameters measured during a 6-min walk test (6-MWT) impart reliable prognostic information. Sit-to-stand tests (STSTs) are field exercise tests that are easier to implement than the 6-MWT in daily practice.

OBJECTIVES: The aims of the study were to test the reproducibility and compare 2 STSTs (the 1-min STST [1-STST] and the semi-paced 3-min chair rise test [3-CRT]) in IPF, and to determine if selected physiological parameters (speed of displacement and changes in pulse oxygen saturation [SpO2]) are interchangeable between the STSTs and the 6-MWT.

METHODS: Thirty-three patients with stable IPF were studied in 3 French expert centers. To test reproducibility, intra-class correlations (ICCs) of parameters measured during tests performed 7-14 days apart were calculated. To test interchangeability, the agreement and correlation of physiological responses measured during STSTs and during 6-MWT were studied.

RESULTS: Vertical displacements and changes in SpO2 during both STSTs were reproducible, with ICCs ranging from 0.78 [0.63-0.87] to 0.95 [0.92-0.97]. Vertical displacements during 1-STST and 3-CRT were correlated with 6-MWT distance (correlation coefficients (r) of 0.72 and 0.77, respectively; p < 0.001). Similarly, correlations were found between changes in SpO2 measured during the 2 STSTs and the 6-MWT, with coefficients ranging from 0.73 to 0.91 (p < 0.001). Distance walked and SpO2 during 6-MWT were well estimated from vertical displacement and SpO2 during the 2 STSTs, respectively.

CONCLUSION: The correlations found between the 2 STSTs and the 6-MWT suggest that STSTs may be of interest to assess displacement and exercise-induced changes in SpO2 in IPF patients.

PMID:33849043 | DOI:10.1159/000515335

J Bone Joint Surg Am. 2021 Apr 21;103(8):668-680. doi: 10.2106/JBJS.20.01139.

ABSTRACT

BACKGROUND: The prevalence of nonunion after a proximal humeral fracture (PHF) and the risk factors for its occurrence are poorly defined. We aimed to estimate the rate of nonunion in nonoperatively treated patients and to produce a clinical model for its prediction.

METHODS: Two thousand two hundred and thirty adult patients (median age, 72 years [range, 18 to 103 years]; 75.5% were female) with a PHF underwent assessment of fracture union using standard clinical evaluation and conventional radiographs. We assessed the prevalence of nonunion and measured the effect of 19 parameters on healing. Best statistical practices were used to construct a multivariate logistic regression model. The PHF assessment of risk of nonunion model (PHARON) was externally validated in a subsequent prospectively collected population of 735 patients, treated by the same protocol in our institution.

RESULTS: Overall, 231 (10.4%) of 2,230 patients developed nonunion. Only 3 (0.8%) of 395 patients with a head-shaft angle (HSA) of >140° developed nonunion; in this cohort, none of the measured candidate variables were independently predictive of nonunion on multivariate logistic regression analysis. In the larger cohort of 1,835 patients with an HSA of ≤140°, 228 (12.4%) developed nonunion. Decreasing HSA, increasing head-shaft translation (HST), and smoking were independently predictive of nonunion on multivariate analysis. The prevalence of nonunion was very low (1%) in the majority with both an HSA of >90° and HST of <50%, whereas the risk was much higher (83.7%) in the 8.3% with an HSA of ≤90° and HST of ≥50%. In both groups, the prevalence of nonunion was much higher in smokers.

CONCLUSIONS: The prevalence of nonunion after PHF is higher than previously reported. Most patients have favorable risk-factor estimates and a very low risk of this complication, but a smaller subgroup is at much higher risk. The risk can be accurately estimated with PHARON, using standard clinical assessment tools.

LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

PMID:33849049 | DOI:10.2106/JBJS.20.01139

Gerontology. 2021 Apr 13:1-9. doi: 10.1159/000515161. Online ahead of print.

ABSTRACT

INTRODUCTION: The Multidimensional Prognostic Index (MPI) is a validated tool for assessing mortality risk in hospitalised patients. We aimed to evaluate whether the MPI predicted mortality and the risk of developing diverticular disease (DD) complications in older patients.

METHODS: This is a multicentre study conducted in January 2016-March 2018. All patients with DD aged 65 years and older were included. Patients were stratified into three groups according to MPI groups (1, low risk; 2, moderate risk; 3, high risk). Risk of developing DD complications and mortality rate were assessed. Bivariate models were fitted.

RESULTS: One hundred hospitalised patients with DD (mean age 77.9 ± 10.6 years, 53 female patients) were included. Patients with higher MPI groups were more likely to develop DD complications. In particular, 12 (46.2%), 21 (52.5%), and 28 (82.4%) patients with complicated DD were distributed to the MPI 1, MPI 2, and MPI 3 groups (p = 0.0063), respectively. Two patients died in the MPI 1, 4 in the MPI 2, and 29 in the MPI 3 group, with mortality rates of 4.0 per 100 person-year (95% confidence interval [CI] 1.0-15.9), 5.6 (95% CI 2.1-15.0), and 89.2 (95% CI 62-130), respectively (log-rank test p < 0.001). In bivariate analysis, after adjustment for age >80 years, Charlson Comorbidity Index >4, DD complications, and the presence of thromboembolism, higher MPI group was independently associated with higher mortality. Those in the MPI 3 group experienced a greater risk of 1-year hospital readmission (p < 0.001).

CONCLUSION: MPI predicted mortality in patients with DD and also correlated with the risk of developing DD complications. Studies focussing on possible pathophysiological mechanisms between DD complications and MPI are needed.

PMID:33849017 | DOI:10.1159/000515161

Dermatology. 2021 Apr 13:1-8. doi: 10.1159/000515158. Online ahead of print.

ABSTRACT

BACKGROUND: Mobile teledermoscopy is an emerging technology that involves imaging and digitally sending dermoscopic images of skin lesions to a clinician for assessment. High-quality, consistent images are required for accurate telediagnoses when monitoring lesions over time. To date there are no tools to assess the quality of sequential images taken by consumers using mobile teledermoscopy. The purpose of this study was to develop a tool to assess the quality of images acquired by consumers.

METHODS: Participants imaged skin lesions that they felt were concerning at baseline, 1-, and 2-months. A checklist to assess the quality of consumer sequential imaging of skin lesions was developed based on the International Skin Imaging Collaboration guidelines. A scale was implemented to grade the quality of the images: 0 (low) to 18 (very high). Intra- and inter-reliability of the checklist was assessed using Bland-Altman analysis. Using this checklist, the consistency with which 85 sets of images were scored by 2 evaluators were compared using Kappa statistics. Items with a low Kappa value <0.4 were removed.

RESULTS: After reliability testing, 5 of the items were removed due to low Kappa values (<0.4) and the final checklist included 13 items surveying: lesion selection; image orientation; lighting; field of view; focus and depth of view. Participants had a mean age of 41 years (range 19-73), and 67% were female. Most participants (84%, n = 71/85) were able to select and image the correct lesion over time for both the dermoscopic and overview images. Younger participants (<40 years old) scored significantly higher (8.1 ± 2.1) on the imaging checklist compared to older participants (7.1 ± 2.4; p = 0.037). Participants had most difficulty with consistent image orientation.

CONCLUSIONS: This checklist could be used as a triage tool to filter images acquired by consumers prior to telediagnosis evaluation, which would improve the efficiency and accuracy of teledermatology and teledermoscopy processes. It may also be used to provide feedback to the consumers to improve image acquisition over time.

PMID:33849022 | DOI:10.1159/000515158

Child Abuse Negl. 2021 Apr 10;117:105069. doi: 10.1016/j.chiabu.2021.105069. Online ahead of print.

ABSTRACT

BACKGROUND: Adult substance use contributes to high rates of child maltreatment, adverse parenting, and poor child well-being outcomes. The Children’s Bureau in the Administration for Children and Families, U.S. Department of Health and Human Services funded the Regional Partnership Grant (RPG) program to improve safety, well-being, and permanency outcomes for children at risk of or in out-of-home placements because of caregivers’ substance use.

OBJECTIVE: This study estimates the effect of the RPG program on adult parenting and recovery outcomes, as well as child safety, permanency, and well-being outcomes.

PARTICIPANTS AND SETTING: This study included samples from three RPG projects funded in 2014. A total of 437 families were included in the evaluation: 198 enrolled in RPG and 239 in the comparison group.

METHODS: Outcomes included both administrative data and standardized instruments collected at program entry and exit. Impacts were calculated by comparing regression-adjusted differences between RPG participants and a well-matched comparison group.

RESULTS: The RPG program showed two favorable and statistically significant impacts on adult outcomes: reduced trauma symptoms (ES = -0.25, p = 0.02), and depressive symptoms (ES = -0.25, p = 0.03). In addition, children enrolled in RPG had reduced behavior problems (ES = -0.31, p = 0.02) and reduced executive functioning deficits (ES = -0.31, p = 0.04). There were no significant impacts observed for child safety and permanency outcomes.

CONCLUSIONS: The RPG approach has produced several favorable impacts on key mental health needs of caregivers and children, establishing foundational evidence of program effectiveness. Additional evaluation research is necessary to understand the effectiveness on additional outcomes with a larger, more generalizable sample.

PMID:33848956 | DOI:10.1016/j.chiabu.2021.105069

J Neural Eng. 2021 Apr 13. doi: 10.1088/1741-2552/abf772. Online ahead of print.

ABSTRACT

OBJECTIVE: To explore the viability of developing a computer-aided diagnostic system for Parkinsonian syndromes using dynamic [11C]raclopride PET and T1-weighted MRI data.

APPROACH: The biological heterogeneity of Parkinsonian syndromes renders their statistical classification a challenge. The unique combination of structural and molecular imaging data allowed different classifier designs to be tested. Datasets from dynamic [11C]raclopride PET and T1-weighted MRI scans were acquired from six groups of participants: healthy controls (CTRL n=15), patients with Parkinson’s disease (PD n=27), multiple system atrophy (MSA n=8), corticobasal degeneration (CBD n=6), and dementia with Lewy bodies (DLB n=5). MSA, CBD, and DLB patients were classified into one category designated as atypical parkinsonism (AP). The distribution volume ratio (DVR) kinetic parameters obtained from PET data were used to quantify the reversible tracer binding to D2/D3 receptors in the subcortical regions of interest (ROI). Grey matter (GM) volumes obtained from the MRI data were used to quantify GM atrophy across cortical, subcortical, and cerebellar ROI.

RESULTS: The classifiers CTRL vs PD and CTRL vs AP achieved the highest balanced accuracy combining DVR and GM (DVR-GM) features (96.7%, 92.1%, respectively), followed by the classifiers designed with DVR features (93.3%, 88.8%, respectively), and GM features (69.6%, 86.1%, respectively). In contrast, the classifier PD vs AP showed the highest balanced accuracy (78.9%) using DVR features only. The integration of DVR-GM (77.9%) and GM features (72.7%) produced inferior performances. The classifier CTRL vs PD vs AP showed high weighted balanced accuracy when DVR (80.5%) or DVR-GM features (79.9%) were integrated. GM features revealed poorer performance (59.5%).

SIGNIFICANCE: This work was unique in its combination of structural and molecular imaging features in binary and triple category classifications. We were able to demonstrate improved binary classification of healthy/diseased status (concerning both PD and AP) and equate performance to DVR features in multiclass classifications.

PMID:33848996 | DOI:10.1088/1741-2552/abf772

Acta Haematol. 2021 Apr 13:1-9. doi: 10.1159/000514907. Online ahead of print.

ABSTRACT

OBJECTIVE: The objective of this study was to determine the expression of G protein-coupled receptors (GPCRs) in platelets from adult patients with chronic immune thrombocytopenic purpura (ITP).

METHODS: Peripheral blood samples were collected from 40 patients with chronic ITP in the Second Affiliated Hospital of Shantou University Medical College, and 40 peripheral blood samples from healthy volunteers were collected; expressions of the adenosine diphosphate receptors (P2Y1 and P2Y12), alpha-2A adrenergic receptor (α2A-AR), and thromboxane A2 receptor (TP) in platelets were detected by flow cytometry. Gα protein, protease-activated receptor 1 (PAR1), and protease-activated receptor 4 (PAR4) were analyzed by Western blot and analyzed statistically.

RESULTS: Flow cytometry measurements of mean fluorescence intensities showed platelets from patients with chronic ITP, compared to healthy individuals, had significantly higher levels of P2Y1 (31.4 ± 2.2 vs. 7.8 ± 0.8), P2Y12 (29.6 ± 2.1 vs. 7.2 ± 1.3), α2A-AR (25.8 ± 2.9 vs. 9.8 ± 0.9), and TP (39.8 ± 3.1 vs. 4.7 ± 0.6) (all p < 0.01). Similarly, integrated optical density analysis of Western blots showed that platelets from patients with chronic ITP had significantly higher levels of Gα (1046.3 ± 159.96 vs. 254.49 ± 39.51), PAR1 (832.98 ± 98.81 vs. 203.92 ± 27.47), and PAR4 (1518.80 ± 272.45 vs. 431.27 ± 41.86) (all p < 0.01).

CONCLUSION: Expression of GPCRs is increased in platelets from patients with chronic ITP, suggesting that platelets of chronic ITP may participate in the complicated biological process by means of GPCR-mediated signaling pathways.

PMID:33849009 | DOI:10.1159/000514907

J Environ Manage. 2021 Apr 10;289:112522. doi: 10.1016/j.jenvman.2021.112522. Online ahead of print.

ABSTRACT

COVID-19 pandemic has caused profound impacts on human life and the environment including freshwater ecosystems globally. Despite the various impacts, the pandemic has improved the quality of the environment and thereby creating an opportunity to restore the degraded ecosystems. This study presents the imprints of COVID-19 lockdown on the surface water quality and chemical characteristics of the urban-based Bagmati River Basin (BRB), Nepal. A total of 50 water samples were collected from 25 sites of BRB during the monsoon season, in 2019 and 2020. The water temperature, pH, electrical conductivity, total dissolved solids, dissolved oxygen (DO), and turbidity were measured in-situ, while the major ions, total hardness, biological oxygen demand (BOD), and chemical oxygen demand (COD) were analyzed in the laboratory. The results revealed neutral to mildly alkaline waters with relatively moderate mineralization and dissolved chemical constituents in the BRB. The average ionic abundance followed the order of Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ > NH₄⁺ for cations and HCO₃^–> Cl^– > SO₄^2- > NO₃^– > PO₄^3- for anions. Comparing to the pre-lockdown, the level of DO was increased by 1.5 times, whereas the BOD and COD were decreased by 1.5 and 1.9 times, respectively during the post-lockdown indicating the improvement of the quality water which was also supported by the results of multivariate statistical analyses. This study confirms that the remarkable recovery of degraded aquatic ecosystems is possible with limiting anthropic activities.

PMID:33848878 | DOI:10.1016/j.jenvman.2021.112522

J Biomech. 2021 Apr 5;121:110417. doi: 10.1016/j.jbiomech.2021.110417. Online ahead of print.

ABSTRACT

A frog can jump several times higher than its own height and then land smoothly on the ground. During the buffering phase, both forelimbs touch the ground and compact quickly to absorb most of the impact energy. However, the adjustment of the joint angles of the forelimb and the induced cushioning effect during the landing process have not been thoroughly investigated. In this study, we statistically summarized the angular displacements of forelimb joints with respect to landing velocities by using a high-speed motion capture system. It is found many joint angles were linearly influenced by landing velocity at both ground touching moment and maximum compression moment. Moreover, the double-peak pattern of ground reactive force was measured, which attributes to the forelimb landing and the followed abdomen/hindlimb landing. Before the appearance of the first peak, the compression of the forelimb and the reactive force revealed a linear relationship regardless of velocity, implying that the forelimbs act as a constant stiffness spring in landing. Accordingly, a simple spring-mass model was proposed and verified by simulation for forelimb cushioning of the frog. We anticipate our achievements to inspire the design of future landing mechanisms.

PMID:33848828 | DOI:10.1016/j.jbiomech.2021.110417

J Surg Res. 2021 Apr 10;264:462-468. doi: 10.1016/j.jss.2021.02.044. Online ahead of print.

ABSTRACT

BACKGROUND: Using the platform of morbidity and mortality conference, we developed and executed a combined faculty-resident intervention called “Education M&M” to discuss challenges faced by both parties in the operating room (OR), identify realistic solutions, and implement action plans. This study aimed to investigate the impact of this intervention on resident OR training.

MATERIALS AND METHODS: Two resident case presentations were followed by audience discussion and recommendations regarding actionable solutions aimed at improving resident OR training from an expert faculty panel. Postintervention surveys were completed by participants immediately and 2 mo later to assess perceived short and long-term impact on OR teaching and/or learning and the execution of two recommended solutions. Descriptive statistical analysis was applied.

RESULTS: Immediate post-intervention surveys (n = 44) indicated that 81.8% of participants enjoyed the M&M “a lot”; 90.1% said they would use some or a lot of the ideas presented. Awareness of OR teaching/learning challenges before and after the M&M improved from 3.0 to 3.7 (P = 0.00001) for faculty and 3.0 to 3.9 for trainees (P = 0.00004). Understanding of OR teaching and/or learning approaches improved from 3.1 to 3.7 for faculty (P = 0.00004) and 2.7 to 3.9 for trainees (P = 0.00001). In 2-mo post-intervention surveys, most residents had experienced two recommended solutions (71% and 88%) in the OR, but self-reported changes to faculty behavior did not reach statistical significance.

CONCLUSIONS: A department-wide education M&M could be an effective approach to enhance mutual communication between faculty members and residents around OR teaching/learning by identifying program-specific challenges and potential actionable solutions.

PMID:33848846 | DOI:10.1016/j.jss.2021.02.044