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Aim: This Study Aimed to Assess the Intention to Have a Third Child among Millennial Parents (25–40 years old) with Two Children in a City in Eastern China and to Explore the Influencing Factors Related to Fertility Intention. Design: A cross‐sectional design study. Methods: A convenience sampling method was used to enrol participants of childbearing age who visited two tertiary hospitals in Hang zhou, a city in eastern China, from June 2021 to March 2022. We conducted a face‐to‐face questionnaire survey with 520 participants and calculated the prevalence of intention‐related factors. Multivariate logistic regression was used to analyse the independent influencing factors of fertility intention. Results: In total, 105 (20.2%) participants had the intention to have a third child. The results showed that 'employment status', 'age', 'reasons for wanting a third child', the considered 'biggest barrier to having a third child', 'views on the three‐child policy', 'desired free services', 'supporting work policies' and 'assistance policies' were significant independent influencing factors of intention to have a third child (p‐value < 0.05). The intention of the participants 'over 30 years old' was 2.466 times that of those '30 years old and under', and 'older age/personal health status' was considered the 'biggest barrier to having a third child'. Regarding policy and social reasons, the participants who need 'medical assistance' policy negatively affect the intention to have a third child (OR = 0.453, 95% CI = 0.247–0.830). Implications for Healthcare/Nursing: Nursing plays an important role in health promotion. Nurses can help couples make wise decisions about fertility by providing professional consultation, education, evaluation and support. They can also provide corresponding nursing and guidance to improve couples' health quality and overall reproductive success. Conclusions: The general level of intention to have a third child of Millennial parents with two children is still low. The participants who are 'housewives/househusbands', 'over 30 years old', and satisfied with the state of 'medical assistance' have higher fertility intentions. Patient or Public Contribution: It is particularly meaningful for the policymakers to improve the social support system and raise universal awareness to encourage childbirth. [ABSTRACT FROM AUTHOR]

Aim: To assess the social cognitive elements of the stigma of mental illness (knowledge, attitudes and behaviours) among healthcare professionals (HCPs) in Jordan. Design: A cross‐sectional descriptive design. Methods: A total of 206 HCPs were conveniently recruited from general hospitals in Jordan. The mental attitude, knowledge and intended behaviours scales were used to measure stigma elements. Results: Participants reported a moderate level of knowledge, a moderate negative attitude and a moderate or not greater interest to deal with people with mental health illnesses. The bivariate correlation revealed a negative significant correlation between HCPs' knowledge and attitude, indicating that HCPs with more knowledge significantly have more positive attitude (lower average score) towards those suffering from the illness. A more significant correlation was found between HCPs' knowledge and behaviour. The HCPs who had more knowledge were holding more interest and willingness towards dealing with persons with mental illness. Patient or Public Contribution: Negative attitudes among HCPs demand awareness programmes pertaining to the stigma of mental illness to afford higher standards of practice for patients with mental problems. [ABSTRACT FROM AUTHOR]

Ship present‐weather reports from 1950 to 2019 are used to assess trends in the reporting of precipitation occurrence over the global oceans. Annual reported precipitation frequency shows statistically significant positive trends of up to ∼15% per decade throughout most ocean areas equatorward of 45°. However, latitudes poleward of 45° are dominated by negative trends, some areas of which meet the 95% confidence threshold. Nine smaller regions were subjectively selected for further investigation, revealing that the observed trends, both positive and negative, are often but not always nearly linear, with the amplitude of interannual fluctuations usually being much larger than that expected from random sampling error alone. The annual time series reveal that four comparatively dry areas are associated with the largest overall positive trends, ranging from 8.3% to 12.8% (relative) per decade. Trends were also computed separately for each season, revealing remarkable overall consistency in trends across seasons. Plain Language Summary: Starting with 70 years (1950–2019) of archived ship weather reports from around the world's oceans, we tabulated the frequencies of reports of precipitation as a fraction of the total weather reports on a 1° latitude/longitude grid for each season and year. We then composited these to coarser resolution where necessary to have an adequate sample size. Finally, we computed trends in reported precipitation frequency over the seven‐decade period and tested the trends for statistical significance at the 95% confidence level. We found that statistically significant trends in apparent precipitation frequency affect large areas of the oceans, with positive trends dominating in the warmer and especially drier areas and negative trends dominating at higher latitudes. Key Points: Significant long‐term trends are found in ship reports of precipitation occurrenceTrends are mostly positive equatorward of 45° and negative at higher latitudesReporting biases that could explain the trends cannot be ruled out but have not been identified [ABSTRACT FROM AUTHOR]

Consumption of unhealthy commercial foods and beverages (UCFB) is common among infants and young children living in low- and middle-income countries. Such foods can displace other nutritious foods, however, there is limited evidence on how this consumption tracks across time. This study assessed and tracked UCFB consumption of children living in rural/peri-urban Cambodia during the complementary feeding period, identified UCFB consumption patterns of these children, and explored the association between UCFB consumption and growth. A 6-month longitudinal cohort study was implemented among 567 caregivers of children aged 10-14 months at recruitment. UCFB consumption was estimated each month via a telephone-administered 7-day food frequency questionnaire, and UCFB consumption patterns were identified based on changes in this frequency of consumption over time. The majority of children either maintained (45.7%, n = 246) or developed (43.5%, n = 234) an unhealthy consumption pattern and only 10.8% (n = 58) of children maintained/transitioned into a healthy consumption pattern. High consumers of UCFB at 10-14 months had a 4.7 (CI: 4.7 [3.1-7.2]) times odds of being high consumers of UCFB at 15-19 months (p < 0.001). There was a trend of lower length- for-age z-scores (LAZ) among children maintaining or developing an unhealthy consumption pattern (~-0. SD LAZ) compared to children maintaining/transitioning into a healthy consumption pattern, however, this association was not statistically significant. Findings indicate that high UCFB consumption begins during infancy and tracks into early childhood. National policies and programmes centred on early interventions addressing the use of UCFB for infant and young child feeding are needed. [ABSTRACT FROM AUTHOR]

This paper presents an exact finite-sample statistical procedure for testing hypotheses about the weights of mean-variance efficient portfolios. The estimation and inference procedures on efficient portfolio weights are performed in the same way as for the coefficients in an OLS regression. OLS t- and F-statistics can be used for tests on efficient weights, and when returns are multivariate normal, these statistics have exact t and F distributions in a finite sample. Using 20 years of data on 11 country stock indexes, we find that the sampling error in estimates of the weights of a global efficient portfolio is large. [ABSTRACT FROM AUTHOR]

The article discusses several manifestations of risk within audit sampling procedures, suggesting they are more conceptually significant than commonly theoretically proposed. The implications of risk analysis on sampling methods and the advantages of dollar-unit sampling in particular are described in depth. Several factors of sampling selection are considered, including population characteristic assumptions, the levels of specificity in procedure design, and test objectives. The possibilities of tangible risk within the sampling population, of non-applicability to variable assignment, and error distribution patterns are addressed, providing numerical examples.

Abstract: Maternal undernutrition and mortality remain high in several African countries. Key nutrition and health interventions improve maternal and birth outcomes. Evidence is scarce on how to strengthen health systems to ensure pregnant women and newborns are reached with these interventions. We conducted three quasi‐experimental nonrandomized Community Based Maternal and Neonatal Health and Nutrition projects in regions of Ethiopia, Senegal, and Kenya to demonstrate how proven nutrition interventions could be integrated into health programs to improve knowledge and practices during pregnancy, birth, and postpartum. We evaluated impact on knowledge and practices related to maternal and neonatal care using logistic regression and repeated‐measures models with districts as a fixed variable and adjusted for covariates. Combined country analyses show significant positive effects of the intervention on women receiving first antenatal care visit (ANC) during first trimester (OR = 1.44; p < .001), those consuming any iron and folic acid supplement during their latest pregnancy (OR = 1.60; p = .005), those whose <6 months infants were exclusively breastfed (OR = 2.01; p=.003), those whose delivery was facility based (OR = 1.48; p=.031), and those whose postnatal care was facility based (OR = 2.15; p<.001). There was no significant differences between intervention and control groups regarding one or more and four or more ANC visits, women consuming iron and folic acid for ≥90 days, and early initiation of breastfeeding. We conclude that integrating proven nutrition interventions into health programs at community level improved components of access to and use of ANC, delivery services, and postnatal care by women in three African countries. [ABSTRACT FROM AUTHOR]

Vitamin B6 is important in fetal development, but little is known of the vitamin B6 status of pregnant women and newborns in North America and potential modifying factors. This prospective study determined maternal and cord plasma concentrations of pyridoxal 5′ phosphate (PLP; an indicator of vitamin B6 status) in a convenience sample of 368 Canadian pregnant women and their newborns. The association of maternal intake of vitamin B6 and fetal genetic variants with cord plasma PLP and homocysteine concentrations was also examined. Dietary and supplemental intakes of vitamin B6 were assessed in early and mid to late pregnancy. PLP concentrations were measured in maternal plasma in early pregnancy and at delivery, and in cord plasma. Six fetal variants of the MTHFR and CβS genes were assessed for their association with cord plasma PLP and homocysteine concentrations. Geometric mean (95% CI) PLP concentrations were 107 (98, 116) nmol/L in early pregnancy and 58 (53, 62) nmol/L at delivery, respectively, and 296 (275, 319) nmol/L in cord blood ( p < .0001). During early pregnancy and at delivery, 3.6% and 5.5% of women had plasma PLP concentrations <20 nmol/L, respectively. Ninety eight percent of the women with supplemental B6 intake of at least the recommended dietary allowance had PLP concentrations >20 nmol/L. Fetal genetic variants were not associated with cord PLP and homocysteine concentrations. Vitamin B6 deficiency is uncommon in a cohort of Canadian pregnant women due largely to prevalent vitamin B6 supplement use. [ABSTRACT FROM AUTHOR]

Objective Articular erosions correlate with disability in rheumatoid arthritis (RA). Biologic agents reduce erosion progression in RA, but erosion healing occurs infrequently. This study was undertaken to assess the effects of the anabolic agent teriparatide on joint erosion volume in RA patients treated with a tumor necrosis factor inhibitor (TNFi). Methods We conducted a randomized controlled trial in 24 patients with erosive RA, osteopenia, and disease activity controlled by TNFi treatment for at least 3 months. Half were randomized to receive teriparatide for 1 year and the others constituted a wait-list control group. Subjects and primary rheumatologists were not blinded with regard to treatment assignment, but all outcomes were assessed in a blinded manner. The primary outcome measure was change in erosion volume determined by computed tomography at 6 anatomic sites. Significance within each hand and anatomic site was based on a 2-tailed test, with P values less than 0.05 considered significant. Results Baseline characteristics of the treatment groups were well balanced. After 52 weeks, the median change in erosion volume in the teriparatide group was −0.4 mm3 (interquartile range [IQR] −34.5, 29.6) and did not differ significantly from that in controls (median change +9.1 mm3 [IQR −29.6, 26.4]) ( P = 0.28). No significant difference in change in erosion volume was noted at the radius, ulna, or metacarpophalangeal joints. Bone mineral density improved at the femoral neck and lumbar spine in the teriparatide group. Conclusion Our findings indicate that teriparatide treatment for 1 year does not significantly reduce erosion volume in the hands or wrists of patients with established RA with disease activity controlled by TNFi treatment. [ABSTRACT FROM AUTHOR]

Objective To assess the efficacy and safety of anifrolumab, a type I interferon (IFN) receptor antagonist, in a phase IIb, randomized, double-blind, placebo-controlled study of adults with moderate-to-severe systemic lupus erythematosus (SLE). Methods Patients (n = 305) were randomized to receive intravenous anifrolumab (300 mg or 1,000 mg) or placebo, in addition to standard therapy, every 4 weeks for 48 weeks. Randomization was stratified by SLE Disease Activity Index 2000 score (<10 or ≥10), oral corticosteroid dosage (<10 or ≥10 mg/day), and type I IFN gene signature test status (high or low) based on a 4-gene expression assay. The primary end point was the percentage of patients achieving an SLE Responder Index (SRI[4]) response at week 24 with sustained reduction of oral corticosteroids (<10 mg/day and less than or equal to the dose at week 1 from week 12 through 24). Other end points (including SRI[4], British Isles Lupus Assessment Group [BILAG]-based Composite Lupus Assessment [BICLA], modified SRI[6], and major clinical response) were assessed at week 52. The primary end point was analyzed in the modified intent-to-treat (ITT) population and type I IFN-high subpopulation. The study result was considered positive if the primary end point was met in either of the 2 study populations. The Type I error rate was controlled at 0.10 (2-sided), within each of the 2 study populations for the primary end point analysis. Results The primary end point was met by more patients treated with anifrolumab (34.3% of 99 for 300 mg and 28.8% of 104 for 1,000 mg) than placebo (17.6% of 102) ( P = 0.014 for 300 mg and P = 0.063 for 1,000 mg, versus placebo), with greater effect size in patients with a high IFN signature at baseline (13.2% in placebo-treated patients versus 36.0% [ P = 0.004] and 28.2% [ P = 0.029]) in patients treated with anifrolumab 300 mg and 1,000 mg, respectively. At week 52, patients treated with anifrolumab achieved greater responses in SRI(4) (40.2% versus 62.6% [ P < 0.001] and 53.8% [ P = 0.043] with placebo, anifrolumab 300 mg, and anifrolumab 1,000 mg, respectively), BICLA (25.7% versus 53.5% [ P < 0.001] and 41.2% [ P = 0.018], respectively), modified SRI(6) (28.4% versus 49.5% [ P = 0.002] and 44.7% [ P = 0.015], respectively), major clinical response (BILAG 2004 C or better in all organ domains from week 24 through week 52) (6.9% versus 19.2% [ P = 0.012] and 17.3% [ P = 0.025], respectively), and several other global and organ-specific end points. Herpes zoster was more frequent in the anifrolumab-treated patients (2.0% with placebo treatment versus 5.1% and 9.5% with anifrolumab 300 mg and 1,000 mg, respectively), as were cases reported as influenza (2.0% versus 6.1% and 7.6%, respectively), in the anifrolumab treatment groups. Incidence of serious adverse events was similar between groups (18.8% versus 16.2% and 17.1%, respectively). Conclusion Anifrolumab substantially reduced disease activity compared with placebo across multiple clinical end points in the patients with moderate-to-severe SLE. [ABSTRACT FROM AUTHOR]

Integrating the perspectives of psychological contract and sex differences, this study examines how organizational decision to reduce labour costs influences employees' perceived psychological contract breach and their commitment to their organizations. Using two experiments, we found three-way interaction effects among the decision to reduce labour costs, employee sex, and the managerial control over the decision. The decision of labour costs reduction leads to stronger feelings of psychological contract breach for females when the decision is in low than in high levels of managerial control, but the same decision leads to stronger psychological contract breach for males when the decision is in high than in low levels of managerial control. Furthermore, the indirect effect of labour costs reduction on employees' organizational commitment through psychological contract breach is also contingent upon the interaction between employee sex and managerial control. Our findings expand the literature of psychological contract and shed light on timely practical issues of management's decisions regarding labour costs reduction. Practitioner points Labour costs reductions in economic downturns lead to different responses from employees, and managers are advised to plan their actions bearing in mind such differences., Management in crisis or difficulties calls for more delicate considerations of employees' psychological feelings towards the organization., Nuanced empirical evidence informs us about the different needs and responses of a diverse group of employees and how their responses contradict. [ABSTRACT FROM AUTHOR]

Background: Personal and family data forms, completed by women referred to breast cancer genetics clinics, are valuable tools for verification and extension of family history, crucial steps in accurate risk evaluation. A significant minority of women do not complete and return these forms, despite reminders, even when completion is a pre‐requisite for a clinic appointment. Objective: To facilitate access of women at increased familial risk of breast cancer to screening and counselling services by investigating reasons for non‐return of the forms. Participants and Design: Based on a single regional ‘breast cancer family’ service in the UK, Analysis of quantitative data comparing women who did not return forms (n = 55) with those who had done so (n = 59), together with qualitative evaluation of potential barriers to form‐completion through semi‐structured telephone interviews with a random subset of ‘non‐returners’ (n = 23). Results: Non‐returners have higher proportions of the very young (below the age at which surveillance could be offered) and of women from lower social deprivation categories. Interviews revealed that the majority of non‐returners are anxious, rather than unconcerned about their breast cancer risk and circumstances and attitudes contributed to non‐compliance. Twenty‐one participants confirmed that they would welcome an appointment at a ‘breast cancer family’ clinic, but nine did not attend for the appointment. They were significantly younger than those who attend, but were not at lower familial risk. Discussion and Conclusions: Many women who fail to complete and return a family history form would benefit from risk assessment and genetic counselling. Several steps are suggested that might help them access the relevant services. [ABSTRACT FROM AUTHOR]

Although playing a crucial role for the prevention of long-term health impairment, interventions aiming at the improvement of employees' recovery processes are still scarce. In this study, we therefore investigated the effectiveness of a low-dose mindfulness intervention for recovery from work. In addition, differential responding to the treatment in terms of treatment-by-baseline interactions was studied. A sample of 140 employees participated in a randomized field experiment with a self-training and a wait-list control group. Three central recovery processes (psychological detachment, sleep quality, and sleep duration) were assessed with event-sampling methodology involving daily measurements over 10 workdays. Growth curve analyses revealed intervention effects on sleep quality and sleep duration. No effects were found for psychological detachment after work and for the proposed treatment-by-baseline interactions. Our findings are discussed in the context of occupational health promotion in general and mindfulness-based interventions in specific. Practitioner points Although daily recovery from the demands of work has been shown to be vital for employee well-being and performance, research on how workplace interventions can help improve recovery is still scarce., This study investigated the effectiveness of a brief, economic mindfulness intervention on processes that are vital for recovery - psychological detachment, sleep quality, and sleep duration., Findings revealed positive effects of the intervention on sleep quality and duration, but not on psychological detachment. [ABSTRACT FROM AUTHOR]

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Background Itraconazole is commonly used to treat systemic fungal infections in dogs, but problems exist with absorption and cost. Objective To determine oral bioequivalence of generic and compounded itraconazole compared to original innovator (brand name) itraconazole in healthy dogs. Animals Nine healthy, adult research Beagle dogs. Methods A randomized, 3-way, 3-period, crossover design with an 8-day washout period. After a 12-hour fast, each dog received 100 mg (average: 10.5 mg/kg) of either innovator itraconazole, an approved human generic capsule, or compounded itraconazole (compounded using a commercially available compounding vehicle) with a small meal. Plasma was collected at predetermined intervals for high pressure liquid chromatography analysis. Concentration data were analyzed using noncompartmental pharmacokinetics to determine area under the curve ( AUC), peak concentration ( CMAX), and terminal half-life. Bioequivalence tests compared generic and compounded itraconazole to the reference formulation. Results Average ratios of compounded and generic formulations to the reference formulation of itraconazole for AUC were 5.52% and 104.2%, respectively, and for CMAX were 4.14% and 86.34%, respectively. A test of bioequivalence using 2 one-sided tests and 90% confidence intervals did not meet bioequivalence criteria for either formulation. Conclusion and Clinical Importance Neither generic nor compounded itraconazole is bioequivalent to the reference formulation in dogs. However, pharmacokinetic data for generic formulation were similar enough that therapeutic concentrations could be achieved. Compounded itraconazole produced such low plasma concentrations, it is unlikely to be effective; therefore, compounded itraconazole should not be used in dogs. [ABSTRACT FROM AUTHOR]

The range of resources that a species uses (i.e. its niche breadth) might determine the geographical area it can occupy, but consensus on whether a niche breadth-range size relationship generally exists among species has been slow to emerge. The validity of this hypothesis is a key question in ecology in that it proposes a mechanism for commonness and rarity, and if true, may help predict species' vulnerability to extinction. We identified 64 studies that measured niche breadth and range size, and we used a meta-analytic approach to test for the presence of a niche breadth-range size relationship. We found a significant positive relationship between range size and environmental tolerance breadth ( z = 0.49), habitat breadth ( z = 0.45), and diet breadth ( z = 0.28). The overall positive effect persisted even when incorporating sampling effects. Despite significant variability in the strength of the relationship among studies, the general positive relationship suggests that specialist species might be disproportionately vulnerable to habitat loss and climate change due to synergistic effects of a narrow niche and small range size. An understanding of the ecological and evolutionary mechanisms that drive and cause deviations from this niche breadth-range size pattern is an important future research goal. [ABSTRACT FROM AUTHOR]

A common situation in biology is where we have count data and wish to explore whether there is an association between two categorical variables, each with two levels (a 2 × 2 contingency table). The size of the association can be measured using the odds ratio, with a confidence interval for this measure enclosing unity suggesting no evidence of an association. However, there is no universally agreed method for calculating such a confidence interval., Here, we provide a review of some commonly used and recently suggested methods., Of all of the methods currently available, the unconditional approach based on the score statistic was consistently closest to the nominal type I error level in our investigations, and this is the method we generally recommend. This method also offers good agreement with P-values from null hypothesis testing using the method of Fisher-Boschloo., However, some scientists may prefer the recently developed minlike or Blaker methods, which offered better agreement with P-values calculated using Fisher's Exact test or Blaker's Exact test, respectively., Lastly, where calculation without use of a computer is required, we recommend the Woolf method with Haldane- Anscombe correction. [ABSTRACT FROM AUTHOR]

Context and objective Shared decision making is especially advocated for preference-sensitive decisions. We investigated whether physicians' recommendations pull patients away from their preferred treatment option when making a preference-sensitive decision. Design, participants and methods Inpatients ( N = 102 with schizophrenia, N = 101 with multiple sclerosis) were presented with a hypothetical scenario (the choice between two drugs). They were first asked about their preferences concerning the two drugs and then they received a (fictitious) clinician's recommendation that was contrary to their preferences. Subsequently they made a final choice between the two drugs. Main outcome measures The main outcome measure was whether the patient followed the physician's advice in the hypothetical scenario. Thereby patient's (pre-recommendation) preferences served as a baseline. Results In the decision scenario, about 48% of the patients with schizophrenia and 26% of the patients with multiple sclerosis followed the advice of their physician and thus chose the treatment option that went against their initial preferences. Patients who followed their physician's advice were less satisfied with their decision than patients not following their physician's advice (schizophrenia: t = 2.61, P = 0.01; multiple sclerosis: t = 2.67, P = 0.009). Discussion and conclusions When sharing decisions with patients, physicians should be aware that their advice might influence patients' decisions away from their preferred treatment option. They should encourage their patients to identify their own preferences and help to find the treatment option most consistent with them. [ABSTRACT FROM AUTHOR]

In this article, we develop regression models with cross-classified responses. Conditional independence structures can be explored/exploited through the selective inclusion/exclusion of terms in a certain functional ANOVA decomposition, and the estimation is done nonparametrically via the penalized likelihood method. A cohort of computational and data analytical tools are presented, which include cross-validation for smoothing parameter selection, Kullback-Leibler projection for model selection, and Bayesian confidence intervals for odds ratios. Random effects are introduced to model possible correlations such as those found in longitudinal and clustered data. Empirical performances of the methods are explored in simulation studies of limited scales, and a real data example is presented using some eyetracking data from linguistic studies. The techniques are implemented in a suite of R functions, whose usage is briefly described in the appendix. The Canadian Journal of Statistics 39: 591-609; 2011. © 2011 Statistical Society of Canada [ABSTRACT FROM AUTHOR]

This study was designed to assess brain-derived neurotrophic factor (BDNF) as a possible candidate for enhanced cognition in breastfed infants. The study was conducted on 42 infants, 4-6 months old, who were classified according to their feeding pattern into breastfed group, formula-fed group and mixed-feeding group. Each infant was subjected to history taking, clinical examination, estimation of the level of BDNF by Enzyme-Linked Immunosorbent Assay (ELISA) technique and assessment by Bayley scale of infant development-second edition (BSID-II). The current study revealed that breastfed group had higher BSID-II scores followed by mixed-fed group then formula-fed one, yet these results reached statistical significance only in total behaviour rating scale (TBRS) and Motor Quality Percentile rank values. Additionally, breastfed infants had significantly higher values of BDNF when compared to those receiving formula milk. Negative correlations between BDNF and both weight for age and weight for length scores were detected. Furthermore, significant positive correlation was detected between BDNF and TBRS. Regression analysis studies revealed that breastfeeding is the most determinant factor for BDNF, TBRS and Motor Quality Percentile rank values. Serum BDNF levels are significantly higher in breastfed infants and shows positive correlations with the results of BSID-II. Given that simultaneous increase in brain BDNF occurs due to onsite production, transport from the periphery or both, it is prudent to hypothesize that BDNF could be one of the factors responsible for the enhanced cognition detected in breastfed infants. [ABSTRACT FROM AUTHOR]

Objectives: Hypoxia has been observed when infants undergo lumbar puncture in a tight flexed lateral recumbent position. This study used sonographic measurements of lumbar interspinous spaces to investigate the anatomic necessity and advantage derived from this tight flexed positioning in infants. Methods: This was a brief, prospective, observational study of a convenience sample of patients. Twenty-one healthy infants under 1 month of age were scanned in two positions: prone in a spine- neutral position and lateral recumbent with their knees bent into their chest and their neck flexed. In each position, a 5- to 10-MHz linear array transducer was used to scan midline along the lumbar spinous processes in the sagittal plane. The distances between the spinous processes were measured near the ligamentum flavum using the ultrasound machine's calipers. Pulse oximetry was monitored on all infants during flexed positioning. Results: In the spine-neutral position, all studied interspinous spaces were much wider than a 22-gauge spinal needle (diameter 0.072 cm). The mean (±SD) interspinous spaces for L3-4, L4-5, and L5-S1 in a spine-neutral position were 0.42 (±0.07), 0.37 (±0.06), and 0.36 (±0.11) cm, respectively. Flexing the infants increased the mean lumbar interspinous spaces at L3-4, L4-5, and L5-S1 by 31, 51, and 44%, respectively. Conclusions: This study verified that tight, lateral flexed positioning substantially enhances the space between the lumbar spinous processes and that a spine-neutral position also allows for a large enough anatomic interspinous space to perform lumbar puncture. However, further clinical research is required to establish the feasibility of lumbar puncture in a spine-neutral position. [ABSTRACT FROM AUTHOR]

Objectives: This study examined selected effects of the proper use of nonparametric inferential statistical methods for analysis of nonnormally distributed data, as exemplified by emergency department length of stay (ED LOS). The hypothesis was that parametric methods have been used inappropriately for evaluation of ED LOS in most recent studies in leading emergency medicine (EM) journals. To illustrate why such a methodologic flaw should be avoided, a demonstration, using data from the National Hospital Ambulatory Medical Care Survey (NHAMCS), is presented. The demonstration shows how inappropriate analysis of ED LOS increases the probability of type II errors. Methods: Five major EM journals were reviewed, January 1, 2004, through December 31, 2007, and all studies with ED LOS as one of the reported outcomes were reviewed. The authors determined whether ED LOS was analyzed correctly by ascertaining whether nonparametric tests were used when indicated. An illustrative analysis of ED LOS was constructed using 2006 NHAMCS data, to demonstrate how inferential testing for statistical significance can deliver differing conclusions, depending on whether nonparametric methods are used when indicated. Results: Forty-nine articles were identified that studied ED LOS; 80% did not perform a test of normality on the ED LOS data. Data were not normally distributed in all 10 of the studies that did perform such tests. Overall, 43% failed to use appropriate nonparametric methods. Analysis of NHAMCS data confirmed that failure to use nonparametric bivariate tests results in type II statistical error and in multivariate models with less explanatory power (a smaller R 2 value). Conclusions: ED LOS, a key ED operational metric, is frequently analyzed incorrectly in the EM literature. Applying parametric statistical tests to such nonnormally distributed data reduces power and increases the probability of a type II error, which is the failure to find true associations. Appropriate use of nonparametric statistics should be a core component of statistical literacy because such use increases the validity of ED research and quality improvement projects. ACADEMIC EMERGENCY MEDICINE 2010; 17:1113-1121 © 2010 by the Society for Academic Emergency Medicine [ABSTRACT FROM AUTHOR]

The study of differences among groups is an interesting statistical topic in many applied fields. It is very common in this context to have data that are subject to mechanisms of loss of information, such as censoring and truncation. In the setting of a two-sample problem with data subject to left truncation and right censoring, we develop an empirical likelihood method to do inference for the relative distribution. We obtain a nonparametric generalization of Wilks' theorem and construct nonparametric pointwise confidence intervals for the relative distribution. Finally, we analyse the coverage probability and length of these confidence intervals through a simulation study and illustrate their use with a real data set on gastric cancer. [ABSTRACT FROM AUTHOR]

ACADEMIC EMERGENCY MEDICINE 2010; 17:940–950 © 2010 by the Society for Academic Emergency Medicine Objectives: The objectives of this study were to determine concordance of emergency department (ED) management of acute myocardial infarction (AMI) with guideline recommendations and to identify ED and patient characteristics predictive of higher guideline concordance. Methods: The authors conducted a chart review study of ED AMI care as part of the National Emergency Department Safety Study (NEDSS). Using a primary hospital discharge diagnosis of AMI (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM], codes 410.XX), a random sample of ED visits for AMI in 58 urban EDs across 20 U.S. states between 2003 and 2006 were identified. Concordance with American College of Cardiology/American Heart Association (ACC/AHA) guideline recommendations was evaluated using five individual quality measures and a composite concordance score. Concordance scores were calculated as the percentage of eligible patients who received guidelines-recommended care. These percentage scores were rescaled from 0 to 100, with 100 indicating perfect concordance. Results: The cohort consisted of 3,819 subjects; their median age was 65 years, and 62% were men. The mean (± standard deviation [SD]) ED composite concordance score was 61 ± 8), with a broad range of values (42 to 84). Except for aspirin use (mean concordance, 82), ED concordance scores were low (beta-blocker use, 56; timely electrocardiogram [ECG], 41; timely fibrinolytic therapy, 26; timely ED disposition for primary percutaneous coronary intervention [PCI] candidates, 43). In multivariable analyses, older age (beta-coefficient per 10-year increase, −1.5; 95% confidence interval [CI] = −2.4 to −0.5) and southern EDs (beta-coefficient, −5.2; 95% CI = −9.6 to −0.9) were associated with lower guideline concordance, whereas ST-segment elevation on initial ED ECG was associated with higher guideline concordance (beta-coefficient, 3.6; 95% CI = 1.5 to 5.7). Conclusions: Overall ED concordance with guideline-recommended processes of care was low to moderate. Emergency physicians should continue to work with other stakeholders in AMI care, such as emergency medical services (EMS) and cardiologists, to develop strategies to improve care processes. [ABSTRACT FROM AUTHOR]

This paper extends Imbens and Manski's (2004) analysis of confidence intervals for interval identified parameters. The extension is motivated by the discovery that for their final result, Imbens and Manski implicitly assumed locally superefficient estimation of a nuisance parameter. I reanalyze the problem both with assumptions that merely weaken this superefficiency condition and with assumptions that remove it altogether. Imbens and Manski's confidence region is valid under weaker assumptions than theirs, yet superefficiency is required. I also provide a confidence interval that is valid under superefficiency, but can be adapted to the general case. A methodological contribution is to observe that the difficulty of inference comes from a preestimation problem regarding a nuisance parameter, clarifying the connection to other work on partial identification. [ABSTRACT FROM AUTHOR]

This paper considers inference in a broad class of nonregular models. The models considered are nonregular in the sense that standard test statistics have asymptotic distributions that are discontinuous in some parameters. It is shown in Andrews and Guggenberger (2009a) that standard fixed critical value, subsampling, and m out of n bootstrap methods often have incorrect asymptotic size in such models. This paper introduces general methods of constructing tests and confidence intervals that have correct asymptotic size. In particular, we consider a hybrid subsampling/fixed-criticalvalue method and size-correction methods. The paper discusses two examples in detail. They are (i) confidence intervals in an autoregressive model with a root that may be close to unity and conditional heteroskedasticity of unknown form and (ii) tests and confidence intervals based on a post-conservative model selection estimator. [ABSTRACT FROM AUTHOR]

Hierarchical statistical models are increasingly being used to describe complex ecological processes. The data cloning (DC) method is a new general technique that uses Markov chain Monte Carlo (MCMC) algorithms to compute maximum likelihood (ML) estimates along with their asymptotic variance estimates for hierarchical models. Despite its generality, the method has two inferential limitations. First, it only provides Wald-type confidence intervals, known to be inaccurate in small samples. Second, it only yields ML parameter estimates, but not the maximized likelihood values used for profile likelihood intervals, likelihood ratio hypothesis tests, and information-theoretic model selection. Here we describe how to overcome these inferential limitations with a computationally efficient method for calculating likelihood ratios via data cloning. The ability to calculate likelihood ratios allows one to dó hypothesis tests, construct accurate confidence intervals and undertake information-based model selection with hierarchical models in a frequentist context. To demonstrate the use of these tools with complex ecological models, we reanalyze part of Gause's classic Paramecium data with state-space population models containing both environmental noise and sampling error. The analysis results include improved confidence intervals for parameters, a hypothesis test of laboratory replication, and a comparison of the Beverton-Holt and the Ricker growth forms based on a model selection index. [ABSTRACT FROM AUTHOR]

Inférence pour des données d'échantrillonnage en présence d'erreurs de classement L'auteur propose une approche inférentielle pour des données d'échantrillonnage en présence d'erreurs de classement. Il appuie son analyse sur les modèles de Bohn & Wolfe (1994) et de Frey (2007a, b), dont il estime les paramètres en minimisant une mesure de distance. Il se sert ensuite des modèles ajustés pour calibrer des intervalles de confiance et des tests. Il montre la validité de son approche à l'aide de simulations et en illustre l'application en construisant des intervalles de confiance non paramétriques pour la surface médiane des feuilles de pommier couvertes par un aérosol. [ABSTRACT FROM AUTHOR]

Conventional bootstrap- t intervals for density functions based on kernel density estimators exhibit poor coverages due to failure of the bootstrap to estimate the bias correctly. The problem can be resolved by either estimating the bias explicitly or undersmoothing the kernel density estimate to undermine its bias asymptotically. The resulting bias-corrected intervals have an optimal coverage error of order arbitrarily close to second order for a sufficiently smooth density function. We investigated the effects on coverage error of both bias-corrected intervals when the nominal coverage level is calibrated by the iterated bootstrap. In either case, an asymptotic reduction of coverage error is possible provided that the bias terms are handled using an extra round of smoothed bootstrapping. Under appropriate smoothness conditions, the optimal coverage error of the iterated bootstrap- t intervals has order arbitrarily close to third order. Examples of both simulated and real data are reported to illustrate the iterated bootstrap procedures. [ABSTRACT FROM AUTHOR]

Comparison of two samples can sometimes be conducted on the basis of analysis of receiver operating characteristic (ROC) curves. A variety of methods of point estimation and confidence intervals for ROC curves have been proposed and well studied. We develop smoothed empirical likelihood-based confidence intervals for ROC curves when the samples are censored and generated from semiparametric models. The resulting empirical log-likelihood function is shown to be asymptotically chi-squared. Simulation studies illustrate that the proposed empirical likelihood confidence interval is advantageous over the normal approximation-based confidence interval. A real data set is analysed using the proposed method. [ABSTRACT FROM AUTHOR]

The two-stage design is popular in epidemiology studies and clinical trials due to its cost effectiveness. Typically, the first stage sample contains cheaper and possibly biased information, while the second stage validation sample consists of a subset of subjects with accurate and complete information. In this paper, we study estimation of a survival function with right-censored survival data from a two-stage design. A non-parametric estimator is derived by combining data from both stages. We also study its large sample properties and derive pointwise and simultaneous confidence intervals for the survival function. The proposed estimator effectively reduces the variance and finite-sample bias of the Kaplan–Meier estimator solely based on the second stage validation sample. Finally, we apply our method to a real data set from a medical device postmarketing surveillance study. [ABSTRACT FROM AUTHOR]

The Regression of Offspring on Mid-Parent (ROMP) method is a test of association between a quantitative trait and a candidate locus. ROMP estimates the trait heritability and the heritability attributable to a locus and requires genotyping the offspring only. In this study, the theory underlying ROMP was revised (ROMPrev) and extended. Computer simulations were used to determine the type I error and power of the test of association, and the accuracy of the locus-specific heritability estimate. The ROMPrev test had good power at the 5% significance level with properly controlled type I error. Locus-specific heritability estimates were, on average, close to simulated values. For non-zero locus-specific heritability, the proposed standard error was downwardly biased, yielding reduced coverage of 95% confidence intervals. A bootstrap approach with proper coverage is suggested as a second step for loci of interest. ROMPrev was applied to a study of cardiovascular-related traits to illustrate its use. An association between polymorphisms within the fibrinogen gene cluster and plasma fibrinogen was detected (p < 0.005) that accounted for 29% of the estimated fibrinogen heritability. The ROMPrev method provides a computationally fast and simple way of testing for association and obtaining accurate estimates of locus-specific heritability while minimizing the genotyping required. [ABSTRACT FROM AUTHOR]

Intervalles statistiques libres obtenus par échantrillonnage L'auteur montre comment construire des intervalles statistiques libres à partir d'un échantrillon. Il traite des cas des intervalles de confiance, de tolérance et de prévision. Il montre comment calculer leur probabilité de couverture et il compare leur performance à celle des intervalles fondés sur l'échantillonnage aléatoire simple. Il conclut que les intervalles déduits d'un échantrillon sont au moins aussi bons que leur pendant classique dans la plupart des cas d'intérět, quoique la nature des gains qu'ils procurent dépende du type d'intervalle considéré. [ABSTRACT FROM AUTHOR]

Forecasting population decline to a certain critical threshold (the quasi-extinction risk) is one of the central objectives of population viability analysis (PVA), and such predictions figure prominently in the decisions of major conservation organizations. In this paper, we argue that accurate forecasting of a population's quasi-extinction risk does not necessarily require knowledge of the underlying biological mechanisms. Because of the stochastic and multiplicative nature of population growth, the ensemble behaviour of population trajectories converges to common statistical forms across a wide variety of stochastic population processes. This paper provides a theoretical basis for this argument. We show that the quasi-extinction surfaces of a variety of complex stochastic population processes (including age-structured, density-dependent and spatially structured populations) can be modelled by a simple stochastic approximation: the stochastic exponential growth process overlaid with Gaussian errors. Using simulated and real data, we show that this model can be estimated with 20–30 years of data and can provide relatively unbiased quasi-extinction risk with confidence intervals considerably smaller than (0,1). This was found to be true even for simulated data derived from some of the noisiest population processes (density-dependent feedback, species interactions and strong age-structure cycling). A key advantage of statistical models is that their parameters and the uncertainty of those parameters can be estimated from time series data using standard statistical methods. In contrast for most species of conservation concern, biologically realistic models must often be specified rather than estimated because of the limited data available for all the various parameters. Biologically realistic models will always have a prominent place in PVA for evaluating specific management options which affect a single segment of a population, a single demographic rate, or different geographic areas. However, for forecasting quasi-extinction risk, statistical models that are based on the convergent statistical properties of population processes offer many advantages over biologically realistic models. [ABSTRACT FROM AUTHOR]

This article gives conditions under which the nonparametric instrumental variables estimator of Hall and Horowitz ( Annals of Statistics 33 (December 2005), 2904–2929) is asymptotically normally distributed. With sufficiently large samples, the asymptotic normality result can be used to form confidence intervals for the unknown function that is estimated by the Hall–Horowitz procedure. The article reports the results of a Monte Carlo investigation of the finite-sample coverage probabilities of the confidence intervals. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to provide theoretical justification for some existing methods for constructing confidence intervals for the sum of coefficients in autoregressive models. We show that the methods of Stock (1991), Andrews (1993), and Hansen (1999) provide asymptotically valid confidence intervals, whereas the subsampling method of Romano and Wolf (2001) does not. In addition, we generalize the three valid methods to a larger class of statistics. We also clarify the difference between uniform and pointwise asymptotic approximations, and show that a pointwise convergence of coverage probabilities for all values of the parameter does not guarantee the validity of the confidence set. [ABSTRACT FROM AUTHOR]

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The large deviation modified likelihood ratio statistic is studied for testing a variance component equal to a specified value. Formulas are presented in the general balanced case, whereas in the unbalanced case only the one-way random effects model is studied. Simulation studies are presented, showing that the normal approximation to the large deviation modified likelihood ratio statistic gives confidence intervals for variance components with coverage probabilities very close to the nominal confidence coefficient. [ABSTRACT FROM AUTHOR]

Procédure de tests multiples utilisant les probabilités des contre-hypothèses unilatérales, avec application aux études génomiques Cet article vise à faire le lien entre l'analyse bayésienne et la théorie fréquentiste dans le contexte des comparaisons multiples. Les auteurs montrent que lorsque l'on teste l'égalité de deux moyennes, la probabilité a posteriori de la contre-hypothèse unilatérale, définie comme un demi-espace, partage avec le seuil observé la propriété d'uniformité sous l'hypothèse nulle. Ultimement, la probabilité a posteriori peut donc être utilisée dans le même esprit qu'un seuil observé dans le cadre de la procédure de Benjamini-Hochberg et dans chacune de ses généralisations. [ABSTRACT FROM AUTHOR]

A U-statistic is not easy to apply or cannot be applied in hypothesis testing when it is degenerate or has an indeterminate degeneracy under the null hypothesis. A class of two-stage U-statistics (TU-statistics) is proposed to remedy these drawbacks. Both the asymptotic distributions under the null and the alternative of TU-statistics are shown to have simple forms. When the degeneracy is indeterminate, the Pitman asymptotic relative efficiency of a TU-statistic dominates that of the incomplete U-statistics. If the kernel is degenerate under the null hypothesis but non-degenerate under the alternative, a TU-statistic is proved to be more powerful than its corresponding U-statistic. Applications to testing independence of paired angles in ecology and marine biology are given. Finally, a simulation study shows that a TU-statistic is more powerful than its corresponding incomplete U-statistic in almost all cases under two settings. [ABSTRACT FROM AUTHOR]

This paper is concerned with inference about a function g that is identified by a conditional moment restriction involving instrumental variables. The paper presents a test of the hypothesis that g belongs to a finite-dimensional parametric family against a nonparametric alternative. The test does not require nonparametric estimation of g and is not subject to the ill-posed inverse problem of nonparametric instrumental variables estimation. Under mild conditions, the test is consistent against any alternative model. In large samples, its power is arbitrarily close to 1 uniformly over a class of alternatives whose distance from the null hypothesis is O(n~'/2), where n is the sample size. In Monte Carlo simulations, the finite-sample power of the new test exceeds that of existing tests. [ABSTRACT FROM AUTHOR]

The likelihood ratio statistic for testing pointwise hypotheses about the survival time distribution in the current status model can be inverted to yield confidence intervals (CIs). One advantage of this procedure is that CIs can be formed without estimating the unknown parameters that figure in the asymptotic distribution of the maximum likelihood estimator (MLE) of the distribution function. We discuss the likelihood ratio-based CIs for the distribution function and the quantile function and compare these intervals to several different intervals based on the MLE. The quantiles of the limiting distribution of the MLE are estimated using various methods including parametric fitting, kernel smoothing and subsampling techniques. Comparisons are carried out both for simulated data and on a data set involving time to immunization against rubella. The comparisons indicate that the likelihood ratio-based intervals are preferable from several perspectives. [ABSTRACT FROM AUTHOR]

We simulated the effects of missing information on statistical distributions of animal response that covaried with measured predictors of habitat to evaluate the utility and performance of quantile regression for providing more useful intervals of uncertainty in habitat relationships. These procedures were evaluated for conditions in which heterogeneity and hidden bias were induced by confounding with missing variables associated with other important processes, a problem common in statistical modeling of ecological phenomena. Simulations for a large (N = 10000) finite population representing grid lo- cations on a landscape demonstrated various forms of hidden bias that might occur when the effect of a measured habitat variable on some animal was confounded with the effect of another unmeasured variable. Quantile (0 ≤ τ ≤ 1) regression parameters for linear models that excluded the important, unmeasured variable revealed bias relative to parameters from the generating model. Depending on whether interactions of the measured and unmeasured variables were negative (interference interactions) or positive (facilitation interactions) in simulations without spatial structuring, either upper (τ > 0.5) or lower (τ < 0.5) quantile regression parameters were less biased than mean rate parameters. Heterogeneous, nonlinear response patterns occurred with correlations between the measured and unmeasured variables. When the unmeasured variable was spatially structured, variation in parameters across quantiles associated with heterogeneous effects of the habitat variable was reduced by modeling the spatial trend surface as a cubic polynomial of location co- ordinates, but substantial hidden bias remained. Sampling (n 20-300) simulations demonstrated that regression quantile estimates and confidence intervals constructed by inverting weighted rank score tests provided valid coverage of these parameters. Local forms of quantile weighting were required for obtaining correct Type I error rates and confidence interval coverage. Quantile regression was used to estimate effects of physical habitat resources on a bivalve (Macomona liliana) in the spatially structured landscape on a sandflat in a New Zealand harbor. Confidence intervals around predicted 0.10 and 0.90 quantiles were used to estimate sampling intervals containing 80% of the variation in densities in relation to bed elevation. Spatially structured variation in bivalve counts estimated by a cubic polynomial trend surface remained after accounting for the nonlinear effects of bed elevation, indicating the existence of important spatially structured processes that were not adequately represented by the measured habitat variables. [ABSTRACT FROM AUTHOR]

This article extends recent results [Scand. J. Statist. 28 (2001) 699] about exact non-parametric inferences based on order statistics with progressive type-II censoring. The extension lies in that non-parametric inferences are now covered where the dependence between involved order statistics cannot be circumvented. These inferences include: (a) tolerance intervals containing at least a specified proportion of the parent distribution, (b) prediction intervals containing at least a specified number of observations in a future sample, and (c) outer and/or inner confidence intervals for a quantile interval of the parent distribution. The inferences are valid for any parent distribution with continuous distribution function. The key result shows how the probability of an event involving k dependent order statistics that are observable/uncensored with progressive type-II censoring can be represented as a mixture with known weights of corresponding probabilities involving k dependent ordinary order statistics. Further applications/developments concerning exact Kolmogorov-type confidence regions are indicated. [ABSTRACT FROM AUTHOR]

Fieller's confidence set C [ABSTRACT FROM AUTHOR]

II existe plusieurs méthodes pour tester l'égalité de plusieurs traitements versus l'hypothése que tous les traitements sont meilleurs qu'un traitement témoin. Mentionnons le test de Dunnett, le test du rapport des vraisemblances de Bartholomew, le test du contraste optimal de Abelson-Tukey et Schaafsma-Smid, ainsi que le test des contrastes multiples de Mukerjee, Robertson et Wright. On propose un nouveau test basé sur une approximation du test du rapport des vraisemblances de Bartholomew. Ce lest utilise un cône circulate à la place du cône correspondant à l'hypothése alternative. Le test basé sur un cône circulaire a, comme le test de Bartholomew, d'excellentes propriétés relativement à la puissance. De plus, il a l'avantage d'être plus facile à calculer et peut être utilisé avec des tailles échantillonnales inégales. [ABSTRACT FROM AUTHOR]

Des tests sans biais sont obtenus dans plusieurs situations. Le premier modele considéré est celui où l'on teste l'homogénéité de k+ 1 populations indépendantes caractérisées par une famille exponentielle dépendant d'un paramètre, contre une alternative stipulant un ordre de la forme d'une cime (θ [ABSTRACT FROM AUTHOR]

Dans cet article on considère le probleme de comparer et de tester des relations d'ordre entre des fonctions de percentiles liées aux durées de vie résiduelles. On introduit des représentations du type R-R et on développe une approche générate pour ce problème. [ABSTRACT FROM AUTHOR]

Considérons un modèle ďanalyse de la variance multidimensionnelle généralisée et supposons que la distribution de la matrice des résidus soit invariante par rapport à toute transformation orthogonale. Dans cet article, nous déterminons des régions de confiance pour une matrice de moyennes de ce modèle; les régions obtenues sont invariantes et leur volume normalisé est aussi petit que possible en moyenne. Nous considérons deux groupes ďinvariance différents: le groupe complet habituel et un sous-groupe moyennable satisfaisant la condition de Hunt- Stein. Un choix particulier de la constante de normalisation nous permet de déterminer des régions de confiance conditionnellement optimales. Nous présentons les résultats de calculs numériques permettant de comparer une région de confiance conditionnellement minimax à la region de confiance conditionnellement optimale et complètement invariante correspondant au test du rapport de vraisemblance. [ABSTRACT FROM AUTHOR]

Cet article s'applique à ľanalyse de données de dénombrement résultant de phénomènes de jumelage. Les paires formées par le jumelage ďé1éments 'semblables' sont cependant exclues. Plusieurs modèles sont proposés et analysés. On s'attache surtout à développer des méthodes aptes à déceler les paires qui se manifestent plus (ou moins) souvent que ne le voudrait le hasard. [ABSTRACT FROM AUTHOR]