An Exploration of Pathologies of Multilevel Principal Components Analysis in Statistical Models of Shape

3D facial surface imaging is a useful tool in dentistry and in terms of diagnostics and treatment planning. Between-groups PCA (bgPCA) is a method that has been used to analyse shapes in biological morphometrics, although various “pathologies” of bgPCA have recently been proposed. Monte Carlo (MC) simulated datasets were created here in order to explore “pathologies” of multilevel PCA (mPCA), where mPCA with two levels is equivalent to bgPCA. The first set of MC experiments involved 300 uncorrelated normally distributed variables, whereas the second set of MC experiments used correlated multivariate MC data describing 3D facial shape. We confirmed previous results of other researchers that indicated that bgPCA (and so also mPCA) can give a false impression of strong differences in component scores between groups when there is none in reality. These spurious differences in component scores via mPCA reduced strongly as the sample sizes per group were increased. Eigenvalues via mPCA were also found to be strongly effected by imbalances in sample sizes per group, although this problem was removed by using weighted forms of covariance matrices suggested by the maximum likelihood solution of the two-level model. However, this did not solve problems of spurious differences between groups in these simulations, which was driven by very small sample sizes in one group here. As a “rule of thumb” only, all of our experiments indicate that reasonable results are obtained when sample sizes per group in all groups are at least equal to the number of variables. Interestingly, the sum of all eigenvalues over both levels via mPCA scaled approximately linearly with the inverse of the sample size per group in all experiments. Finally, between-group variation was added explicitly to the MC data generation model in two experiments considered here. Results for the sum of all eigenvalues via mPCA predicted the asymptotic amount for the total amount of variance correctly in this case, whereas standard “single-level” PCA underestimated this quantity.

Sociodemographic and Medical Determinants of Quality of Life in Long-Term Childhood Acute Lymphoblastic Leukemia Survivors Enrolled in EORTC CLG Studies

Background: due to increasing survival rates in childhood acute lymphoblastic leukemia (ALL), the number of survivors has been expanding. A significant proportion of these survivors can experience long-term emotional and psychosocial problems. However, the exact risk factors remain inconclusive. We investigated potential risk factors for decreased daily life quality and life challenges in long-term childhood ALL survivors enrolled between 1971 and 1998 in EORTC studies. Methods: self-report questionnaires were collected from 186 survivors (109 females; mean age at diagnosis 5.62 years, range 0.2–14.7; median time since diagnosis of 20.5 years (12.9–41.6)), including the Short-Form Health Survey (SF-12) and Impact of Cancer-Childhood Survivors (IOC-CS). Multivariable linear regression models were used to assess the impact of gender, age at diagnosis, relapse/second neoplasm, National Cancer Institute (NCI) risk group and cranial radiotherapy on 2 subscales of the SF-12 (physical and mental health) and five subscales of the IOC-CS (life challenges, body and health, personal growth, thinking and memory problems and socializing). Results: mental component scores of SF-12 were not significantly associated with any risk factor. Physical component scores were lower in relapsed, irradiated and NCI high-risk patients. Regarding IOC-CS negative impact subscales, life challenges was more negatively impacted by cancer in female, younger (i.e., <6 years) and relapsed patients. Regarding the positive impact scales, personal growth was more positively impacted in relapsed patients, whereas body and health, and socializing, were less positively impacted in these patients, compared to non-relapsed patients. Socializing was more positively impacted in older patients (>6 years). Conclusions: this study demonstrates that long-term outcomes can be both adverse and positive, depending on the patient’s demographic and clinical characteristics. Younger, female, and relapsed patients might encounter more life challenges years after their disease, while physical challenges could occur more often in relapsed and high-risk patients. Finally, the positive effect on socializing in the older patients sheds new light on the importance of peer interactions for this subgroup. Specific individual challenges thus need specialized support for specific subgroups.

The effects of grazing on daily caloric intake and dietary quality

Background The duration and frequency of eating occasions has been identified as a factor contributing to poor dietary quality among U.S. adults. The objective of this study is to examine whether grazing, defined as eating more than three times a day, affects total daily caloric intake and dietary quality measured by the 2015 Healthy Eating Index (HEI-2015). Methods We used a multivariate individual fixed-effects model to compare the caloric intake and dietary quality of individuals who grazed on 1 day but not another. This allowed us to control for differences in individual food intake and diet quality preferences among study participants. We use the National Health and Nutrition Examination Survey (NHANES), 2007-2018, and include data for adults aged 18 years or older who reported 2 days of dietary intake and were not pregnant or lactating (n = 27,775). Results Grazing increased total daily caloric intake by 205 cal and increased the daily HEI score by 0.59 points. Grazing increased HEI component scores for total fruit, whole fruit, and refined grains, and decreased HEI component scores for saturated fats. Morning grazing increased total daily caloric intake by 159 cal and increased the daily HEI score by 0.87 points — primarily by increasing component scores for total fruit, whole fruit, whole grains, total dairy, seafood and plant proteins, and sodium. Evening grazing increased daily caloric intake by 76 cal and decreased the daily HEI score by 0.41 points — primarily by decreasing the component scores for total fruit, whole grains, fatty acids, and saturated fats. Evening grazing increased HEI component scores for sodium and refined grains. Conclusions Grazing increases daily caloric intake and can decrease dietary quality (particularly when grazing in the evening).

Analysis of leaf phenotypic diversity of some Hevea Accessions/clones conserved at the Institute of Agricultural Research for Development (IRAD) Ekona, Cameroon

This study was carried out to estimate leaf morphological diversity of some accessions/clones from IRRDB 1981 Hevea germplasm collection conserved at IRAD Ekona, to determine the importance of leaf morphological descriptors in differentiating accessions/clones. A total of 36 clones/ accessions were characterized using 6 leaf morphological descriptors. Analysis of variance showed that there were significant differences in the leaf morphological parameters for the studied clones. The Principal Component Analysis (PCA) showed that all leaf descriptors were informative and contributed significantly to the variation. The first 2 Principal Component scores (PCs) accounted for 88% of the total variation. The cluster analysis based on significant PCs grouped all accessions and clones in to 6 main clusters at the distance of 1.5. This study permits the characterization of Hevea accessions and clones in to diverse groups using leaf morphological descriptors; hence this will be advantageous for production of diverse genotypes during breeding programs to broaden the Hevea gene pool.

Healthy eating index-2015 and breast cancer: a case-control study

Purpose Recently, evidences have suggested that healthy eating index (HEI), an index-based dietary pattern, may be a predictor for the risk of cancer. This paper aims to examine the association of HEI-2015 and its all components scores with the risk of breast cancer (BC), separately, among Iranian women. Design/methodology/approach In the present hospital-based, case-control study, 150 age-matched of cases (newly diagnosed female) and 150 controls were recruited. Data of dietary habits and anthropometric measures were obtained, and eventually, the HEI-2015 score was calculated. Multivariate odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the relationship between the risk of BC across tertiles (Ts) of total HEI-2015 and its all component scores. Findings The results presented that in adjusted model, there was no significant difference between total HEI-2015 (p = 0.14) and its all component scores (p > 0.09) of healthy subjects and females with BC. Moreover, multivariable logistic regression analyses indicated that HEI-2015 score was not associated with the risk of BC in either crude (p-trend = 0.94) or adjusted (p-trend = 0.73) analyses. In the analyses of HEI-2015 components scores, it was observed that the scores of grains (OR, 0.53; 95% CI, 0.30–0.94) and total protein foods (OR, 0.13; 95% CI, 0.02–0.58) may have a relation with BC risk in crude model but after adjusting for BC risk factors, the mentioned associations changed to non-significant. Originality/value The findings of current study suggested that there was no significant association of total HEI-2015 and its components scores, independently, with BC incidence among Iranian women.

Frequency of Meals Prepared Away from Home and Nutrient Intakes among US Adolescents (NHANES 2011–2018)

Frequency of consuming foods prepared away from home has been associated with lower diet quality among adults and adolescents in several earlier studies. Nutrient and food group intake and Healthy Eating Index (HEI)-2015 scores were compared among a U.S. nationally representative sample of adolescents (12–19 years, n = 3975) by frequency of consuming food prepared away from home ≤2 times/week (n = 2311) versus >2 times/week (n = 1664) using National Health and Nutrition Examination Survey (NHANES) data from 2011–2018. Regression analyses were used to compare intakes among adolescents by frequency of eating meals prepared away from home adjusting for covariates. Older (16–19 years) vs. younger (12–15 years) adolescents and those from homes with higher vs. lower family income to poverty ratios had greater frequency of eating meals prepared away from home. Intakes of nutrients of concern for adolescents including choline, vitamin D, potassium, magnesium, fiber, phosphorus, folate, iron, and total HEI-2015 scores and component scores for total vegetables, and greens and beans were lower among adolescents who consumed meals prepared away from home more vs. less often. However, no differences were noted among food group intakes considered good sources of nutrients of concern such as total fruit, total vegetables, whole grains, and total dairy, except for beans and peas by frequency of eating foods prepared away from home. Greater frequency of eating foods prepared away from home was associated with lower diet quality among adolescents in a nationally representative sample of U.S. adolescents.

Health Conditions, Substance Use, Physical Activity, and Quality of Life in Current and Former Baseball Players

Background: A comprehensive understanding of lifestyle (health conditions and substance use), health-related quality of life (HRQoL), flourishing (holistic representation of health), and physical activity can inform stakeholders (players, coaches, and clinicians) and help improve long-term health across the life span. Purpose: To describe health conditions (comorbidities or diagnoses), substance use, physical activity, HRQoL, and flourishing in current and former collegiate and professional baseball players and to assess the relationship between playing position and HRQoL/flourishing in former baseball players. Study Design: Descriptive epidemiology study. Methods: Eligible participants were those ≥18 years old with ≥1 season of collegiate or professional baseball experience. Participants completed a survey on health conditions (asthma, diabetes, hypertension, hypercholesterolemia, and depression), substance use (tobacco, alcohol, and energy drinks), physical activity (International Physical Activity Questionnaire–Short Form), HRQoL (Veterans Rand 12-Item Health Survey [VR-12] physical and mental component scores), and flourishing (Flourishing Scale). Adjusted multivariable regressions were performed for HRQoL and flourishing. Results: Overall, 260 baseball players opened the survey, and 214 (current players, 97; former players, 117) participated for an 82% response rate. Of the former players, 32% had hypertension or hypercholesterolemia. In addition, 26% of current players had used smokeless tobacco (median, 3 years; interquartile range [IQR], 1-5 years) as compared with 34% of former players (median, 15 years; IQR, 5-25 years). In addition, 14% of current players had used electronic cigarettes (median, 2 years; IQR, 0-4 years) as opposed to 3% of former (median, 3 years; IQR, 2-4 years). Energy drinks were consumed by 31% and 14%, respectively, of current and former players on at least a weekly basis. Current baseball players performed 8667 metabolic equivalents per week of physical activity as opposed to 3931 in former players. Pitching was associated with worse VR-12 Mental Component Scores (–5.0; 95% confidence interval, –9.0 to –1.0). Playing position was not related to VR-12 Physical Component Scores or flourishing in former baseball players. Conclusion: The similar smokeless tobacco prevalence between current and former baseball players suggests that they may start using tobacco products during baseball participation and continue after retirement. Similar reported HRQoL as compared with the general US population and high flourishing and physical activity levels suggest that baseball players may present with good musculoskeletal and psychological health.

Differences in finished case quality between Invisalign and traditional fixed appliances:

ABSTRACT Objectives To compare the treatment and posttreatment effects of Invisalign aligners that incorporated SmartForce features and attachments to traditional fixed appliances. Materials and Methods This randomized controlled trial included 66 patients, 32 aligners, and 34 fixed-appliance patients. The median ages of the aligner and braces patients were 26.7 (interquartile range [IQR]: 9.8) and 25.9 (IQR: 16.6) years, respectively. Pretreatment occlusion was assessed using the ABO Discrepancy Index. Posttreatment (T1) and 6-month retention (T2) occlusions were quantified using the ABO Objective Grading System (OGS) scores. Results The braces group finished treatment significantly (P &lt; .001) earlier (0.4 years) than the aligner group. The median DI scores for the aligner and braces groups were 4.5 and 7.0, respectively, which was a statistically significant (P = .015), but clinically insignificant, difference. There were no statistically significant between-group differences for the total OGS scores or any of the individual component scores at debond (T1) or after 6 months of retention (T2). During the posttreatment period, alignment and overjet worsened significantly in the aligner group, while buccolingual inclinations and occlusal relations improved. Over the same period, alignment worsened in the braces group and buccolingual inclinations improved. There was no statistically significant between-group difference in posttreatment changes of the total OGS scores. Conclusions While patients with simple malocclusions require 4.8 months longer treatment times with aligners than traditional braces, the treatment and 6-month posttreatment occlusal outcomes are similar.