Valentin Rousson

Lausanne University Hospital | CHUV · Institut universitaire de médecine sociale et préventive

The concept of (potential) years of life lost is a measure of premature mortality that can be used to compare the impacts of different specific causes of death. However, interpreting a given number of years of life lost at face value is more problematic because of the lack of a sensible reference value. In this paper, we propose three denominators...

Measuring the health impact of an epidemic using appropriate indicators is necessarily complex. Mortality does not sum up all the issues, but at least it seems to be an objective indicator. There are, however, a number of different mortality indicators, which do not all convey the same message. During the Covid-19 epidemic in Switzerland, the morta...

Introduction Human physical growth, biological maturation, and intelligence have been documented as increasing for over 100 years. Comparing the timing of secular trends in these characteristics could provide insight into what underlies them. However, they have not been examined in parallel in the same cohort during different developmental phases....

Objectives Glucagon-like peptide 1 receptor agonists (GLP1-RA) are indicated for the treatment of type 2 diabetes and more recently for weight loss. The aim of this study was to assess the risks associated with GLP1-RA exposure during early pregnancy. Design This multicentre, observational prospective cohort study compared pregnancy outcomes in wo...

Objectives Trace elements (TEs) are ubiquitous. TE concentrations vary among individuals and countries, depending on factors such as living area, workplaces and diet. Deficit or excessive TEs concentrations have consequences on the proper functioning of human organism so their biomonitoring is important. The aim of this project was to provide refer...

The HOPE score (https://www.hypothermiascore.org) is a validated instrument for estimating the survival probability of patients in hypothermic cardiac arrest with ECLS rewarming. It is based on six patient characteristics: sex, age, mechanism of hypothermia, duration of cardiopulmonary resuscitation, serum potassium and temperature. The HOPE score...

Importance Infants with complex congenital heart disease (cCHD) may experience prolonged and severe stress when undergoing open heart surgery. However, little is known about long-term stress and its role in neurodevelopmental impairments in this population. Objective To investigate potential differences between early adolescents aged 10 to 15 year...

Purpose/background: Trazodone is indicated for the treatment of major depressive disorder, but more frequently prescribed off-label at lower doses for insomnia in women of childbearing age. The aim of this study was to assess the risks linked to trazodone exposure during pregnancy for which limited safety data are available. Methods/procedures:...

Building a score from a questionnaire to predict a binary gold standard is a common research question in psychology and health sciences. When building this score, researchers may have to choose between statistical performance and simplicity. A practical question is to what extent it is worth sacrificing the former to improve the latter. We investig...

Objective During the COVID-19 pandemic, excess mortality has generally been estimated comparing overall mortality in a given year with either past mortality levels or past mortality trends, with different results. Our objective was to illustrate and compare the two approaches using mortality data for Switzerland in 2022, the third year of the COVID...

Aims: Our goal was to study hypothermic cardiac arrest (CA) patients who were not rewarmed by Extracorporeal Life Support (ECLS) but were admitted to a hospital equipped for it. The focus was on whether the decisions of non-rewarming, meaning termination of resuscitation, were compliant with international guidelines based on serum potassium at hos...

This study compares the performance of statistical methods for predicting age-standardized cancer incidence, including Poisson generalized linear models, age-period-cohort (APC) and Bayesian age-period-cohort (BAPC) models, autoregressive integrated moving average (ARIMA) time series, and simple linear models. The methods are evaluated via leave-fu...

Introduction Environmental changes, including globalization, urbanization, social and cultural changes in society, and exposure to modern digital technology undoubtedly have an impact on children’s activity and lifestyle behavior. In fact, marked reductions in children’s physical activity levels have been reported over the years and sedentary behav...

The COVID-19 pandemic that reached Europe in 2020 has often been compared to the Spanish flu pandemic of 1918. In this article, we compare the two pandemics in terms of their respective impacts on the loss of life expectancy at birth in six European countries (France, Italy, the Netherlands, Spain, Sweden, Switzerland) by estimating life expectancy...

The 5A score predicts in-hospital mortality of patients suffering from accidental hypothermia, including those not in cardiac arrest. The HOPE score was specifically developed to predict survival for the subgroup of hypothermic patients in cardiac considered for extracorporeal life support rewarming. The C-statistic in the external validation study...

Objective To quantify the (direct and indirect) impacts of the COVID-19 pandemic on mortality for actual populations of persons living in 12 European countries in 2020. Method Based on demographic and mortality data, as well as remaining life expectancies found in the Human Mortality Database, we calculated a “population life loss” in 2020 for men...

Predicting the short-term evolution of the number of cancers is essential for planning investments and allocating health resources. The objective of this study was to predict the numbers of cancer cases and of the 12 most frequent cancer sites, and their age-standardized incidence rates, for the years 2019–2025 in Switzerland. Projections of the nu...

Importance: In educational settings, children are under pressure to finish their work successfully within required time frames. Existing tools for assessing graphomotor skills measure either quality or speed of performance, and the speed–accuracy trade-off (SAT) in such tools has never been investigated. Objective: We aimed to evaluate a newly deve...

Objective To analyze mortality trends in Switzerland in 2021, the second year of the COVID-19 pandemic. Methods Using data from the Swiss Federal Statistical Office, we compared mortality in Switzerland in 2021 with that of previous years in terms of standardized weekly deaths, standardized (annual) mortality rates (overall and stratified by age a...

To assess the association between postnatal growth and neurodevelopment at the age of 2 years in extremely low gestational age newborns (ELGAN, < 28 weeks’ gestation). Retrospective population-based cohort study including all live born ELGAN in 2006–2012 in Switzerland. Growth parameters (weight, length, head circumference, body mass index) were as...

Several interventions have been used around the world trying to contain the SARS-CoV-2 pandemic, such as quarantine, prohibition of mass demonstrations, isolation of sick people, tracing of virus carriers, semi-containment, promotion of barrier gestures, development of rapid self-tests and vaccines among others. We propose a simple model to evaluat...

Objective To analyze mortality trends in Switzerland in 2021, the second year of the COVID-19 pandemic. Methods Using data from the Swiss Federal Statistical Office, we compared mortality in Switzerland in 2021 with that of previous years in terms of standardized weekly deaths, standardized (annual) mortality rates (overall and stratified by age a...

Objectives Several interventions have been used around the world trying to contain the SARS-Cov-2 pandemic, such as quarantine, prohibition of mass demonstrations, isolation of sick people, tracing of virus carriers, semi-containment, promotion of barrier gestures, development of rapid auto-tests and vaccines among others. We propose a simple model...

Background Most claims-based frailty instruments have been designed for group stratification of older populations according to the risk of adverse health outcomes and not frailty itself. We aimed to develop and validate a tool based on one-year hospital discharge data for stratification on Fried's frailty phenotype (FP). Methods We used a three-st...

Objective The present review is an update of a systematic review that has been published in 2012. Meanwhile, many new clinical trials on resin composites had been published. New materials such as bulk fill resin composites and new glass-ionomer (GIC) based materials had been introduced. The focus of this review was to evaluate the longevity in rela...

In this report, we update previously published results on all-cause mortality in Switzerland in 2020 and extend them to the first half of 2021. Whereas mortality in Switzerland increased by 9.2% in 2020 compared with 2019 as a result of the first two waves of COVID-19, it decreased by about 10.8 % in the first half of 2021 compared with 2020, bring...

Aims: The hypothermia outcome prediction after extracorporeal life support (ECLS) score, or HOPE score, provides an estimate of the survival probability in hypothermic cardiac arrest patients undergoing ECLS rewarming. The aim of this study was to assess the performance of the HOPE score in case reports from the literature. Methods: Cases were iden...

Objective Diagnostic ratios calculated from urinary steroid hormone metabolites are used as a measure for the relative activity of steroidogenic enzymes or pathways in the clinical investigation of steroid metabolism disorders. However, population-based sex- and age-specific reference intervals and day-night differences in adults are lacking. Meth...

[This corrects the article DOI: 10.1371/journal.pone.0214549.].

Objective To quantify excess all-cause mortality in Switzerland in 2020, a key indicator for assessing direct and indirect consequences of the COVID-19 pandemic. Methods Using official data on deaths in Switzerland, all-cause mortality in 2020 was compared with that of previous years using directly standardized mortality rates, age- and sex-specif...

This study assessed the impact of body mass index (BMI) and socioeconomic status (SES) on the Zurich Neuromotor Assessment, second version (ZNA-2), a battery of tests of motor development in typically developing children between 3 and 18 years of age. BMI measurements and international socio-economic index data were taken from the normative sample...

Background The survival of completely buried victims in an avalanche mainly depends on burial duration. Knowledge is limited about survival probability after 60 min of complete burial. Aim We aimed to study the survival probability and prehospital characteristics of avalanche victims with long burial durations. Methods We retrospectively included...

We consider the non‐trivial problem of estimating a health cost repartition among diseases from patients' hospital stays' global costs in the presence of multimorbidity, that is, when the patients may suffer from more than one disease. The problem is even harder in the presence of interactions among the disease costs, that is, when the costs of hav...

Objective To quantify the excess all-cause mortality in Switzerland in 2020, a key indicator for assessing direct and indirect consequences of the COVID-19 pandemic. Methods Using official data on deaths in Switzerland, all-cause mortality in 2020 was compared with that of previous years using directly standardized mortality rates, age- and sex-sp...

Objective: To estimate the basic reproduction number (R0) for COVID-19 in Western Europe. Methods: Data (official statistics) on the cumulative incidence of COVID-19 at the start of the outbreak (before any confinement rules were declared) were retrieved in the 15 largest countries in Western Europe, allowing us to estimate the exponential growth...

Objective To estimate the basic reproduction number (R0) for COVID-19 in Western Europe. Methods Data (official statistics) on the cumulative incidence of COVID-19 at the start of the outbreak (before any confinement rules were declared) were retrieved in the 15 largest countries in Western Europe, allowing us to estimate the exponential growth ra...

Objective: To quantify the excess all-cause mortality in Switzerland in 2020, a key indicator for assessing direct and indirect consequences of the COVID-19 pandemic. Methods: Using official data on deaths in Switzerland, all-cause mortality in 2020 was compared with that of previous years using directly standardized mortality rates, age- and sex-s...

An analysis of excess mortality in Switzerland in 2020 before the 2nd wave of COVID-19 is proposed by comparing the number of deaths observed in 2020 with those of the last five years, while taking into account population growth. Three periods are identified : before, during and after the 1st wave of COVID-19. Over all these periods, a sub-mortalit...

The product‐moment correlation coefficient was introduced 130 years ago by Francis Galton and Karl Pearson as a statistical measure to summarize the association between two (continuous) variables, which is intimately related to regression and the bivariate normal distribution. Since then, many different interpretations from a correlation have been...

Background Most claims-based frailty instruments have been designed for group stratification of older populations according to the risk of adverse health outcomes and not frailty itself. We aimed to develop and validate a tool based on one-year hospital discharge data for stratification on Fried's frailty phenotype (FP). Methods We used a three-sta...

Pasquier, Mathieu, Evelien Cools, Ken Zafren, Pierre-Nicolas Carron, Vincent Frochaux, and Valentin Rousson. Vitals signs in accidental hypothermia. High Alt Med Biol 00:000-000, 2020. Background: Clinical indicators are used to stage hypothermia and to guide management of hypothermic patients. We sought to better characterize the influence of hyp...

This prospective multicentre cohort study investigated pregnancy outcomes after fingolimod use for multiple sclerosis during pregnancy. Pregnancy outcomes of 63 fingolimod and 62 interferon-β-exposed pregnancies were compared. Rates of major congenital anomalies (MCA) were 4.8% (2/42) in the fingolimod group versus 2.3% (1/44) in the interferon-β g...

We consider the nontrivial problem of estimating the health cost repartition among different diseases in the common case where the patients may have multiple diseases. To tackle this problem, we propose to use an iterative proportional repartition (IPR) algorithm, a nonparametric method which is simple to understand and to implement, allowing (amon...

Background and aims: Short screenings for alcohol use disorder (AUD) are crucial for public health purposes, but current self-reported measures have several pitfalls and may be unreliable. The main aim of our study was to provide empirical evidence on the psychometric performance of self-reports currently used. Our research questions were: compare...

Objective: To assess cohort and individual neurodevelopmental stability in children with congenital heart disease across childhood. Study design: The Reachout Study is a cohort study at the University Children's Hospital Zurich. Data from 148 children with congenital heart disease who underwent cardiopulmonary bypass surgery and 1-, 4-, and 6-ye...

Aim: We investigated the association between early amplitude-integrated electroencephalography (aEEG) and cognitive outcome in very preterm infants at early school-age. Methods: This prospective cohort study, conducted in the Department of Neonatology, University Hospital Zurich, Switzerland, from 2009-2012, comprised infants born at less than 3...

Aims: The HOPE score, based on covariates available at hospital admission, predicts the probability of in-hospital survival after extracorporeal life support (ECLS) rewarming of a given hypothermic cardiac arrest patient with accidental hypothermia. Our goal was to externally validate the HOPE score. Methods: We included consecutive hypothermic...

There is a need for a quick, qualitative, reliable, and easy tool to assess gross motor development for practitioners. The aim of this cross-sectional study is to present the Zurich Neuromotor Assessment-Q (ZNA-Q), which assesses static and dynamic balance in children between 3 and 6 years of age in less than 5 min. A total of 216 children (103 boy...

Objective Urinary steroid metabolomics by GC-MS is an established method in both clinical and research settings to describe steroidogenic disorders. However, population-based reference intervals for adults do not exist. Methods We measured daytime and night time urinary excretion of 40 steroid metabolites by GC-MS in 1128 adult participants of Eur...

Calibration curves. Calibration curves are shown for all analytes injected on column in the range from 39 to 20000 fmol. Crosses indicate data points, the solid line represents the linear regression curve and the dotted lines the 95% confidence interval. Axes are plotted in logarithmic scale (base 10). (PDF)

Descriptive analyses of steroid compounds. A descriptive analysis of the 40 steroid compounds measured in urine is shown including one steroid compound per page. Panel (a): boxplots, steroid (log-scale) by sex; Panel (b): Gasser-Müller nonparametric fits and scatter plots, steroid (log-scale) by age and by sex; Panels (c) and (d): boxplots, transfo...

Correlation between day and nighttime urinary excretion (μg/hour) of steroid hormone metabolites in men and in women. The available number of participants is indicated for each metabolite stratified for sex. The correlation between day and nighttime excretion values was assessed by Spearman’s rank correlation coefficient ρ (rho). Rho values were ra...

Statistical methods. The statistical methods applied are described in detail. (PDF)

Example of a selected-ion monitoring chromatogram. A plot of the sum of ion abundances for the selected compound-specific ions on the vertical axis versus the retention time of each characteristic ion on the horizontal axis simultaneously obtained by a GC-MS analysis of urinary steroid derivatives is shown. Multiple chromatographic peaks indicate t...

Published urinary steroid excretion reference values. Quantitative urinary steroid excretion values measured by GC-MS and published since 1986 in adults are shown. Abbreviations: GC: gas chromatography, MS: mass spectrometry, F: female, M: male, d: days, y: years. (PDF)

Baseline characteristics of the reference sample group. The number of participants is indicated for each characteristic and sex group. Categorical variables are described by % and continuous variables by their mean±standard deviation or by their median;25th-75th percentiles. Sex-specific differences were determined by chi squared test or Mann–Whitn...

Sex specific differences in 24 hours urinary excretion of steroid hormone metabolites. The available number of participants is indicated for each metabolite stratified for sex. Metabolites in the unit μg/24 hours are described by their median;25th-75th percentile. Between-group differences were determined by Mann–Whitney U test, and the correspondi...

Day and nighttime specific differences in urinary excretion of steroid hormone metabolites in men and women. The available number of participants is indicated for each metabolite stratified for sex. Metabolites in the unit μg/hour are described by their median;25th-75th percentile. Within-sex differences were determined by Wilcoxon signed-rank test...

Reference curves of steroid compounds. Reference curves of the 40 steroid compounds measured in urine are shown including one steroid compound per page. The percentiles 2.5, 10, 25, 50, 75, 90 and 97.5 of the steroid compounds in function of age and sex are shown on a log-scale. To improve comparison the same scale has been used for men and women....

Background: Human skeletal muscle is composed of a functional and metabolic continuum of slow (Type I) and fast fibers (IIa and IIx). Hybrid fibers co-expressing different myosin heavy chains are also present and seem to be more prominent in aging muscle. Their role is debated; hybrid fibers were reported either in a transitional state, between sl...

Introduction La fragilité est fréquente et constitue un prédicteur important de mortalité et de morbidité dans la population âgée. Elle est également associée à une augmentation de la consommation de soins hospitaliers et ambulatoires. Il apparaît donc primordial de monitorer la population fragile ou à risque de fragilité dans un objectif de planif...

Aim: To analyse the association between early aEEG and cognitive outcome at early school-age in very preterm infants. Methods: Prospective cohort study including infants with gestational age (GA) <32.0 weeks, undergoing continuous aEEG recording during first 4 days of life. Semiquantitative and quantitative (maximum/minimum amplitude) measures were...

Objective To determine growth and its relationship to IQ in children with congenital heart disease (CHD) undergoing cardiopulmonary bypass surgery within the first year of life. Study design Prospective single-center cohort study on 143 children (91 males) with different types of CHD (29 univentricular). Children with recognized genetic disorders...

Introduction Frailty is strongly associated with adverse health outcomes and health care costs in elders. However, we have almost no idea of the prevalence of frail older inpatients in Swiss hospitals. Hospital discharge data could contribute to predicting frailty in these patients, and eventually improving SwissDRGs system or casemix-adjustment....

A pregnancy may end up with (at least) three possible events: live birth, spontaneous abortion, or elective termination, yielding a competing risks issue when studying an association between a risk factor and a pregnancy outcome. Cumulative incidences (probabilities to end up with the different outcomes depending on gestational age) can be estimate...

Aims: Currently, the decision to initiate extracorporeal life support for patients who suffer cardiac arrest due to accidental hypothermia is essentially based on serum potassium level. Our goal was to build a prediction score in order to determine the probability of survival following rewarming of hypothermic arrested patients based on several co...

Objective: To estimate the fatigue resistance of a new translucent zirconia material in comparison to lithium disilicate for 3-unit fixed partial dentures (FPDs). Methods: Eighteen 3-unit FPDs (replacement of first upper molar) with a connector size of 4mm×4mm were dry milled with a five-axis milling machine (Zenotec Select, Wieland, Germany) us...

Background: Metformin is used to treat type 2 diabetes, polycystic ovary syndrome associated infertility, and gestational diabetes. Human studies evaluating the safety of metformin in early pregnancy are scarce. Method: We evaluated the risk of major birth defects and pregnancy losses in a cohort of pregnant women exposed to metformin during fir...

A statistical test can be seen as a procedure to produce a decision based on observed data, where some decisions consist of rejecting a hypothesis (yielding a significant result) and some do not, and where one controls the probability to make a wrong rejection at some pre-specified significance level. Whereas traditional hypothesis testing involves...

A statistical test can be seen as a procedure to produce a decision based on observed data, where some decisions consist of rejecting a hypothesis (yielding a significant result) and some do not, and where one controls the probability to make a wrong rejection at some pre-specified significance level. Whereas traditional hypothesis testing involves...

Analyzing count data is frequent in addiction studies but may be cumbersome, time-consuming, and cause misleading inference if models are not correctly specified. We compared different statistical models in a simulation study to provide simple, yet valid, recommendations when analyzing count data.We used 2 simulation studies to test the performance...