Category: Statistics

Pain Med. 2021 Feb 23;22(2):444-458. doi: 10.1093/pm/pnaa403.

ABSTRACT

OBJECTIVE: This pilot trial examined the effects of a combined intervention of mindfulness meditation followed by aerobic walking exercise compared with a control condition in chronic low back pain patients. We hypothesized that meditation before exercise would reduce disability, pain, and anxiety by increasing mindfulness prior to physical activity compared with an audiobook control group.

PARTICIPANTS: Thirty-eight adults completed either meditation and exercise treatment (MedExT) (n=18) or an audiobook control condition (n=20).

SETTING: Duquesne University Exercise Physiology Laboratory.

DESIGN: A pilot, assessor-blinded, randomized controlled trial.

METHODS: Over a 4-week period, participants in the MedExT group performed 12-17 minutes of guided meditation followed by 30 minutes of moderate-intensity walking exercise 5 days per week. Measures of disability, pain, mindfulness, and anxiety were taken at baseline and postintervention. Pain perception measurements were taken daily.

RESULTS: Compared with the control group, we observed larger improvements in disability in the MedExT intervention, although the changes were modest and not statistically significant (mean between-group difference, -1.24; 95% confidence interval [CI], -3.1 to 0.6). For secondary outcome measures, MedExT increased mindfulness (within-group) from pre-intervention to postintervention (P=0.0141). Additionally, mean ratings of low back pain intensity and unpleasantness significantly improved with time for the MedExT group compared with that of the control group, respectively (intensity P=0.0008; unpleasantness P=0.0022).

CONCLUSION: . Overall, 4 weeks of MedExT produced suggestive between-group trends for disability, significant between-group differences for measures of pain, and significant within-group increases in mindfulness.

PMID:33621332 | DOI:10.1093/pm/pnaa403

Med Phys. 2021 Feb 23. doi: 10.1002/mp.14795. Online ahead of print.

ABSTRACT

PURPOSE: Statistical process control tools such as control charts were recommended by the American Association of Physicists in Medicine (AAPM) Task Group 218 for radiotherapy quality assurance. However, the tools needed to analyze multivariate, correlated data that is often encountered in treatment plan quality measures, are lacking. In this study, we develop quality control tools that can model multivariate plan quality measures with correlations and account for patient-specific risk-factors, without adding a significant burden to clinical workflow.

METHODS AND MATERIALS: A multivariate, quality control chart is developed that includes a risk-adjustment model, Hotelling’s T² statistic, and principal component analysis (PCA). PCA accounts for correlations among a set of organ-at-risk (OAR) dose-volume histogram (DVH) points that serves as proxies for plan quality. Risk-adjustment models estimate the principal components from PCA using a set of patient- and treatment-specific risk factors. The resulting residuals from the risk-adjustment models are used to compute the Hotelling’s T² statistic; the corresponding multivariate control chart is then plotted based on the beta distribution followed by the statistic. Further, the box-cox transformation is used to account for non-normality in DVH points. We investigate the application of the proposed methodology via three multivariate control charts-a conventional chart that ignores risk-adjustment and PCA, a risk-adjusted chart ignoring PCA, and a PCA-based, risk-adjusted chart. These control charts are evaluated on 69 head-and-neck cases.

RESULTS: The conventional multivariate control chart fails to account for important patient-specific risk factors, including volumes and cross-sectional areas of the tumor and OARs and distances in-between. This failure leads to a larger number of false alarms. While the multivariate risk-adjusted control chart is able to reduce false alarms, it fails to account for correlations in DVH points. The multivariate PCA-based, risk-adjusted control chart can detect unusual plans after accounting for the correlations. By replanning, improvements are shown on an unusual plan identified by both risk-adjusted methods.

CONCLUSIONS: The multivariate risk-adjusted control chart developed here enables quality control of plans prior to delivery. This methodology is generic and can be readily applied for other radiotherapy quality assurance protocols, such as gamma analysis pass-rates.

PMID:33621381 | DOI:10.1002/mp.14795

Clin Physiol Funct Imaging. 2021 Feb 23. doi: 10.1111/cpf.12696. Online ahead of print.

ABSTRACT

Flow-mediated vasodilatation (FMD) has become one of the most widely assessed parameters to analyze endothelial and vascular function in cardiovascular medicine. The degree of contribution of nitric oxide (NO) to FMD is inconclusive and varies widely depending on the device used. In this study we used a semi-automatic ultrasound device to analyze to what extent basal NO activity contributes to FMD of the brachial artery. FMD was assessed with the UNEX EF device in a cross-over single blinded randomized study at baseline and then during infusion of either a NO-synthase-inhibitor (NG-monomethyl-L-arginine (L-NMMA)) or saline. The analysis was repeated after 1 week with the alternative infusion of L-NMMA or saline. All measurements were analyzed both automatically and by a technician manually. In total 25 healthy men subjects completed the study. Diastolic blood pressure and heart rate significantly changed during infusion of L-NMMA. Infusion of L-NMMA reduced FMD significantly (-37%, p=0.002). Saline solution had no effect on FMD (+14%, p=0.392). Change in FMD was significantly different between the groups (ΔFMD_L-NMMA vs. ΔFMD_saline , p=0.032). There was a statistically significant correlation between automatically analyzed results and those obtained by an experienced technician (FMD_saline : r=0.822, p<0.001; FMD_L-NMMA : r=0.645, p=0.007). The influence of NO on FMD is approximately 40% if assessed using the UNEX EF. Prior to use FMD as a marker of endothelial dysfunction we should explore different methods including various duration of forearm ischaemia to increase NO dependency of FMD.

PMID:33621423 | DOI:10.1111/cpf.12696

PLoS Comput Biol. 2021 Feb 23;17(2):e1008734. doi: 10.1371/journal.pcbi.1008734. eCollection 2021 Feb.

ABSTRACT

The collective behaviour of animal and human groups emerges from the individual decisions and actions of their constituent members. Recent research has revealed many ways in which the behaviour of groups can be influenced by differences amongst their constituent individuals. The existence of individual differences that have implications for collective behaviour raises important questions. How are these differences generated and maintained? Are individual differences driven by exogenous factors, or are they a response to the social dilemmas these groups face? Here I consider the classic case of patch selection by foraging agents under conditions of social competition. I introduce a multilevel model wherein the perceptual sensitivities of agents evolve in response to their foraging success or failure over repeated patch selections. This model reveals a bifurcation in the population, creating a class of agents with no perceptual sensitivity. These agents exploit the social environment to avoid the costs of accurate perception, relying on other agents to make fitness rewards insensitive to the choice of foraging patch. This provides a individual-based evolutionary basis for models incorporating perceptual limits that have been proposed to explain observed deviations from the Ideal Free Distribution (IFD) in empirical studies, while showing that the common assumption in such models that agents share identical sensory limits is likely false. Further analysis of the model shows how agents develop perceptual strategic niches in response to environmental variability. The emergence of agents insensitive to reward differences also has implications for societal resource allocation problems, including the use of financial and prediction markets as mechanisms for aggregating collective wisdom.

PMID:33621223 | DOI:10.1371/journal.pcbi.1008734

PLoS One. 2021 Feb 23;16(2):e0242257. doi: 10.1371/journal.pone.0242257. eCollection 2021.

ABSTRACT

AIM OF THE WORK: This study aimed at assessing the dominance of risk practices associated with HCV endemicity in Egypt and detecting the behavioral development level concerning different aspects of HCV risk behaviors with respect to age and gender. The survey highlights the most cost-effective strategies that could accelerate HCV elimination in Egypt.

SUBJECTS AND METHODS: A national household survey targeted 3780 individuals (age range: 10-85 years). The sample was a systematic probability proportionate to size from 6 governorates representing the six major subdivisions of Egypt. The indicators used for assessing the behavioral development level towards HCV included six domains: awareness (7 indicators), perceived risk (5 indicators), motivation with the intention to change (4 and 5 indicators for males and females respectively), trial, rejection or adoption (6 and 5 indicators for males and females respectively).

RESULTS: The study revealed that along the continuum of behavior development, the percentage of the participants who acquired half of the scores was as follows: 73.1% aware, 69.8% developed perceived risk, 80.6% motivated with only 28.9% adopting the recommended behaviors, 32% rejected them, 2.3% were in the trial stage versus 35.8% who did not try any. Adolescents had significantly lower levels of development for almost all domains when compared to adults. Statistical higher significance was detected in favor of adults, employees, married, Lower Egypt governorates, and university-educated participants (p<0.001) regarding awareness, perceived risk, and motivation scores. More than half of the participants incorrectly believed that contaminated food, sharing food utilities, contaminated water, mosquitoes, and schistosomiasis would lead to HCV transmission.

CONCLUSION: Egypt would be closer to HCV elimination when cost-effective strategies are directed not towards creating awareness, perceived risk or motivation to change- (at an acceptable level)- but towards motivating adopting risk-reduction behaviors for HCV, tackling misconceptions and reinforcement of social support.

PMID:33621232 | DOI:10.1371/journal.pone.0242257

PLoS One. 2021 Feb 23;16(2):e0247601. doi: 10.1371/journal.pone.0247601. eCollection 2021.

ABSTRACT

CT-based quantitative analysis of any ossification center in the cranium has not previously been carried out due to the limited availability of human fetal material. Detailed morphometric data on the development of ossification centers in the human fetus may be useful in the early detection of congenital defects. Ossification disorders in the cranium are associated with either a delayed development of ossification centers or their mineralization. These aberrations may result in the formation of accessory skull bones that differ in shape and size, and the incidence of which may be misdiagnosed as, e.g., skull fractures. The study material comprised 37 human fetuses of both sexes (16♂, 21♀) aged 18-30 weeks. Using CT, digital image analysis software, 3D reconstruction and statistical methods, the linear, planar and spatial dimensions of the occipital squama ossification center were measured. The morphometric characteristics of the fused ossification center of the occipital squama show no right-left differences. In relation to gestational age, the ossification center of the occipital squama grows linearly in its right and left vertical diameters, logarithmically in its transverse diameters of both the interparietal and supraoccipital parts and projection surface area, and according to a quadratic function in its volume. The obtained numerical findings of the occipital squama ossification center may be considered age-specific references of relevance in both the estimation of gestational age and the diagnostic process of congenital defects.

PMID:33621236 | DOI:10.1371/journal.pone.0247601

PLoS One. 2021 Feb 23;16(2):e0247336. doi: 10.1371/journal.pone.0247336. eCollection 2021.

ABSTRACT

BACKGROUND: Epilepsy is thought to be caused by witchcraft, evil spirit, and God’s punishment for sins in many developing countries. As a result, people with epilepsy and their families usually suffer from stigma, discrimination, depression, and other psychiatric problems. Thus, this study aimed to assess the quality of life and its associated factors among epileptic patients attending public hospitals in North Wollo Zone, Northeast Ethiopia.

METHODS: An institution-based cross-sectional study design was employed in this study. A simple random sampling technique was utilized. Health-related quality of life was measured based on the total score of the Quality of Life in Epilepsy Inventory (QOLIE-31) instrument. Data were entered into Epi-data 3.1 statistical package and exported to SPSS Version 20 for further analysis. Linear regression models were used to assess the relationship between quality of life and the independent variables. Statistically significant values were declared at a P-value of < 0.05.

RESULTS: A total of 395 patients participated in the study making the response rate 98.5%. The mean age of the participants was 32.39 ±10.71 years. More than half, 199 (50.4%) of epileptic patients had an overall weighted average health related quality of life score of mean and above. Male sex (B = 4.34, 95%CI, 0.41, 8.27, P = 0.03), higher educational status (B = 7.18, 95%CI, 1.39, 13.00, P = 0.015) and age at onset of epilepsy (B = 0.237, 95%CI, 0.02, 0.45, P = 0.035) were associated with increased health related quality of life score. On the other hand, family history of epilepsy (B = -4.78, 95%CI,-9.24,-0.33, P = 0.035), uncontrolled seizure (B = -11.08, 95%CI,-15.11,-7.05, P < 0.001), more than 5 pre-treatment number of seizures (B = -4.86, 95%CI,-8.91,-0.81, P = 0.019), poor drug adherence (B = -11.65, 95%CI,-16.06,-7.23, P < 0.001), having moderate (B = -4.526, 95%CI,-8.59,-0.46, P = 0.029) to sever (B = -12.84, 95%CI,-18.30,-7.37, P < 0.001) anxiety and depression, believing that epilepsy is caused by evil spirit (B = -7.04, 95%CI,-11.46,-2.61, P = 0.002), drinking alcohol (B = -5.42, 95%CI,-10.72,-0.13, P = 0.045), and having other co-morbidities (B = -9.35, 95%CI,-14.35,-4.36, P < 0.001) were significantly negatively associated with the health related quality of life score among epileptic patients.

CONCLUSIONS: Only around half of the epileptic patients have a good health-related quality of life. In addition, multiple variables including family history, uncontrolled seizure, and poor drug adherence were associated with quality of life among epileptic patients. Hence, targeting these variables in epilepsy management is recommended.

PMID:33621251 | DOI:10.1371/journal.pone.0247336

Disabil Rehabil. 2021 Feb 23:1-11. doi: 10.1080/09638288.2021.1878394. Online ahead of print.

ABSTRACT

PURPOSE: To describe the extent of participation and engagement in family activities and explore variables potentially impacting on these factors in family activities among girls and young women with Rett syndrome (RTT) under the age of 21.

MATERIALS AND METHODS: The Child Participation in Family Activities (Child-PFA) questionnaire was sent to parents in the target group (n = 42). Additionally, age, number of siblings at home, ambulation level, clinical severity and level of hand function were recorded to explore possible impact. Data were analyzed using descriptive statistics, Fishers exact test and cross-tables.

RESULTS: 23 families participated. Highest degrees of participation and engagement were seen in social and stationary family activities. Indoor activities were frequent and showed high levels of participation and engagement, Outdoor activities were infrequent and showed low levels of participation despite a high degree of engagement. Routine activities were frequent but showed moderate to low participation and engagement. A negative association was found between participation in watching a movie and number of siblings living at home, and positive associations between engagement and age in three family activities.

CONCLUSION: Therapists working with this target group may benefit from focusing on engagement in routine activities and modification of family activities.IMPLICATIONS FOR REHABILITATIONTherapists may benefit from focusing on engagement in routine activities in the goal setting process and intervention as they occur on a daily basis, giving the opportunity for development of new skills.Therapists may benefit from focusing on assistive devices or other compensatory strategies for outdoor activities and activities that require a certain amount of hand function.Therapists may benefit from modifying the family’s activities so that they require more social and mental participation and focus on experiencing different types of sensory input e.g., sound, tactile, visual or vestibular input rather than taking part in the activity by using their hands.

PMID:33621156 | DOI:10.1080/09638288.2021.1878394

J Med Internet Res. 2021 Feb 22. doi: 10.2196/24925. Online ahead of print.

ABSTRACT

BACKGROUND: Forecasting methods rely on trends and averages of prior observations to forecast coronavirus disease 2019 (COVID-19) case counts. COVID-19 forecasts have received much media attention and numerous platforms have been created to inform the public. However, forecasting effectiveness varies by geographic scope and are affected by changing assumptions in behaviors and preventative measures in response to the pandemic. Due to time requirements for developing a COVID-19 vaccine, evidence is needed to inform short-term forecasting method selection at county, health district, and state levels.

OBJECTIVE: COVID-19 forecasts keep the public informed and contribute to public policy. As such, proper understanding of forecasting purposes and outcomes is needed to advance knowledge of health statistics for policy makers and the public. Using publicly available real-time data provided online, we evaluate the performance of seven forecasting methods utilized to forecast cumulative COVID-19 case counts. Forecasts are evaluated based on how well they forecast one-. three-, and seven-days forward when utilizing one-, three-, seven-, or all-prior days’ cumulative case counts during early onset. This study provides an objective evaluation of the forecasting methods to identify forecasting model assumptions that contribute to lower error in forecasting COVID-19 cumulative case growth. This information benefits professionals, decision makers, and the public relying on the data provided by short-term case count estimates at varied geographic levels.

METHODS: One-, three-, and seven-days forecasts are created at the county, health district, and state levels using: (1) a naïve approach; (2) Holt-Winters exponential smoothing (HW); (3) growth rate (Growth); (4) moving average (MA); (5) autoregressive (AR); (6) autoregressive moving average (ARMA); and (7) autoregressive integrated moving average (ARIMA). Forecasts rely on Virginia’s 3,463 historical county-level cumulative case counts from March 7 – April 22, 2020, as reported by The New York Times. Statistically significant results are identified using 95% confidence intervals of Median Absolute Error (MdAE) and Median Absolute Percentage Error (MdAPE) error metrics of the resulting 216,698 forecasts.

RESULTS: Next-day MA forecast with three-day lookback obtained the lowest MdAE (0.67, 0.49-0.84, P < .001) and statistically significantly differs from 39 (66.1%) to 53 (89.8%) of alternatives at each geographic level at a significance level of 0.01. For short-range forecasting, methods assuming stationary means of prior days’ counts outperform methods with assumptions of weak- or non-stationarity means. MdAPE results reveal statistically significant differences across geographic levels.

CONCLUSIONS: For short-range COVID-19 cumulative case count forecasting at the county, health district, and state levels during early onset: (1) MA is effective for forecasting one-, three-, and seven-days’ cumulative case counts; (2) exponential growth is not the best representation of case growth during early onset when the public is aware of the virus; and (3) geographic resolution is a factor in forecasting method selection. (This work received no external funding.).

PMID:33621186 | DOI:10.2196/24925

JMIR Hum Factors. 2021 Feb 22. doi: 10.2196/25724. Online ahead of print.

ABSTRACT

BACKGROUND: Few ICU staffing studies examine collaboration structures among healthcare workers. Knowledge about how healthcare workers (HWs) are connected to care for critically ill COVID-19 (C19) patients provides evidence for characterizing the relationship between team structures, care quality, and patient safety.

OBJECTIVE: To discover the distinctions of teamwork structures in C19 critical care by comparing HW collaboration associated with the management of critically ill patients with and without C19.

METHODS: In this retrospective study, we apply network analysis to the utilization of electronic health records (EHRs) of 76 critically ill patients (38 with and 38 without C19) admitted to a large academic medical center to learn HW collaboration. We use the EHRs for adult patients admitted to the C19 ICU at Vanderbilt University Medical Center (Nashville, Tennessee, USA) between March 17, 2020 and May 31, 2020. We matched each C19 patient on age, gender, and length of stay, with NC19 patients admitted to the Medical ICU (MICU) between December 1, 2019 and February 29, 2020. Then we use two sociometric measurements, including eigencentrality and betweenness, to quantify HWs’ status in the networks. Eigencentrality characterizes the degree to which an HW is likely to be a core person in the collaboration. Betweenness centrality refers to whether an HW lies on the path of others who are not directly connected, which is leveraged to characterize the broad skillsets of an HW. We further measure patient staffing intensity in terms of the number of HWs interacting with the EHR of a patient. We assess the extent to which the core and betweenness status of HWs, as well as patient staffing intensity, in C19 and Non-C19 (NC19) critical care are statistically different using Mann-Whitney U tests at the 95% confidence level.

RESULTS: HWs are likely to more frequently work with each other in C19 than NC19 critical care (median eigencentrality values of 0.096 vs. 0.057, respectively; p = 1.5×10e-9). Internal medicine physicians exhibit a higher core status in the C19 critical care than NC19 (p = 1.2 ×10e-3). Nurse practitioners exhibit a more betweenness status in the C19 than NC19 care (p = 3.10 ×10e-4). In comparison to the NC19 setting, the EHRs of C19 critically ill patients were utilized by a larger number of internal medicine nurse practitioners (p = 1.27 ×10e-5), cardiovascular nurses (p = 8.48 ×10e-6) and surgical ICU nurses (p = 1.62 ×10e-3), as well as a smaller number of resident physicians (p = 5.96 ×10e-4).

CONCLUSIONS: Network analysis methodologies and EHR utilization data provide a novel way to learn distinctions of collaboration structures in C19 critical care, which can be leveraged by healthcare organizations to understand the novel additions the C19 brings to the collaboration structure in urgent care.

PMID:33621187 | DOI:10.2196/25724