Effect of mechanical insufflation-exsufflation for ineffective cough on weaning duration in diseases of the peripheral or central nervous system (MEDINE): study protocol for a randomised controlled trial in a neurological weaning centre.

INTRODUCTION: Patients with neurological or neurosurgical disease can suffer from impaired cough, which may result in life-threatening retention of tracheobronchial secretions, atelectasis, pneumonia and finally death. Due to a lack of alternatives and pathophysiological plausibility, the application of mechanical insufflation-exsufflation (MI-E) has already become international standard care in neuromuscular disease and spinal cord injury although a lack of evidence for efficacy. High-quality studies to support the use of MI-E in neurological and neurosurgical patients during weaning from mechanical ventilation are missing. The goal of this exploratory study is to display the effect size of MI-E intervention on the duration of mechanical ventilation and additional outcomes. METHODS AND ANALYSIS: One hundred adult patients with a cough deficiency or retention of secretion admitted to a neurological intensive care unit (ICU) are planned to be recruited for this randomised controlled trial. Patients are randomised 1:1 to receive either MI-E or best standard care. Observation will take place until discharge from the hospital, death or end of the study period. The primary endpoint of this trial is the duration of mechanical ventilation from randomisation until successful weaning. The outcome will be analysed with Kaplan-Meier estimation and competing risks analyses. Secondary endpoint is the proportion of patients with successful weaning. Further outcomes will include the incidence of hospital-acquired pneumonia, mortality, decannulation rate, length of stay on the ICU and the total score of the Glasgow Coma Scale. ETHICS AND DISSEMINATION: The study was approved by the Medical Ethics Committee of the University of Oldenburg. The findings of this study will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: DRKS00020981.

Flexible semiparametric mode regression for time-to-event data.

The distribution of time-to-event outcomes is usually right-skewed. While for symmetric and moderately skewed data the mean and median are appropriate location measures, the mode is preferable for heavily skewed data as it better represents the center of the distribution. Mode regression has been introduced for uncensored data to model the relationship between covariates and the mode of the outcome. Starting from nonparametric kernel density based mode regression, we examine the use of inverse probability of censoring weights to extend mode regression to handle right-censored data. We add a semiparametric predictor to add further flexibility to the model and we construct a pseudo Akaike's information criterion to select the bandwidth and smoothing parameters. We use simulations to evaluate the performance of our proposed approach. We demonstrate the benefit of adding mode regression to one's toolbox for analyzing survival data on a pancreatic cancer data set from a prospectively maintained cancer registry.

Weighted expectile regression for right-censored data.

Expectile regression can be used to analyze the entire conditional distribution of a response, omitting all distributional assumptions. Among its benefits are computational simplicity, efficiency, and the possibility to incorporate a semiparametric predictor. Due to its advantages in full data settings, we propose an extension to right-censored data situations, where conventional methods typically focus only on mean effects. We propose to extend expectile regression with inverse probability weights. Estimates are easy to implement and computationally simple. Expectiles can be converted to more easily interpreted tail expectations, that is, the expected residual life. It provides a meaningful effect measure, similar to the hazard rate. The results from an extensive simulation study are presented, evaluating consistency and sensitivity to violations of assumptions. We use the proposed method to analyze survival times of colorectal cancer patients from a regional certified high volume cancer center.

School-related experience and performance with inflammatory bowel disease: results from a cross-sectional survey in 675 children and their parents.

OBJECTIVE: We describe school performance and experience in children with inflammatory bowel disease (IBD) across Germany and Austria. Predictors of compromised performance and satisfaction were evaluated to identify subgroups of increased risk. DESIGN: This cross-sectional analysis was based on a postal survey in children aged 10-15 with Crohn's disease, ulcerative colitis or unclassified IBD and their families. Multivariate regression analysis was used to assess influential factors on parental satisfaction with school, attending advanced secondary education (ASE), having good marks and having to repeat a class. Satisfaction was assessed based on the Child Healthcare-Satisfaction, Utilisation and Needs instrument (possible range 1.00-5.00). RESULTS: Of 1367 families contacted, 675 participated in the study (49.4%). Sixty-eight participants (10.2%) had repeated a year, 312 (46.2%) attended ASE. The median school satisfaction score was 2.67 (IQR 2.00-3.33). High socioeconomic status (SES) and region within Germany were predictive for ASE (OR high SES 8.2, 95% CI 4.7 to 14.2). SES, female sex and region of residence predicted good marks. Grade retention was associated with an active disease course (OR 2.7, 95% CI 1.4 to 5.3) and prolonged periods off school due to IBD (OR 3.9, 95% CI 1.8 to 8.6). CONCLUSIONS: A severe disease course impacted on the risk of grade retention, but not on type of school attended and school marks. Low satisfaction of parents of chronically ill children with the school situation underlines the need for a more interdisciplinary approach in health services and health services research in young people.