Simple Excel and ICD-10 based dataset calculator for the Charlson and Elixhauser comorbidity indices

Background The Charlson and Elixhauser Comorbidity Indices are the most widely used comorbidity assessment methods in medical research. Both methods are adapted for use with the International Classification of Diseases, which 10th revision (ICD-10) is used by over a hundred countries in the world. Available Charlson and Elixhauser Comorbidity Index calculating methods are limited to a few applications with command-line user interfaces, all requiring specific programming language skills. This study aims to use Microsoft Excel to develop a non-programming and ICD-10 based dataset calculator for Charlson and Elixhauser Comorbidity Index and to validate its results with R- and SAS-based methods. Methods The Excel-based dataset calculator was developed using the program’s formulae, ICD-10 coding algorithms, and different weights of the Charlson and Elixhauser Comorbidity Index. Real, population-wide, nine-year spanning, index hip fracture data from the Estonian Health Insurance Fund was used for validating the calculator. The Excel-based calculator’s output values and processing speed were compared to R- and SAS-based methods. Results A total of 11,491 hip fracture patients’ comorbidities were used for validating the Excel-based calculator. The Excel-based calculator’s results were consistent, revealing no discrepancies, with R- and SAS-based methods while comparing 192,690 and 353,265 output values of Charlson and Elixhauser Comorbidity Index, respectively. The Excel-based calculator’s processing speed was slower but differing only from a few seconds up to four minutes with datasets including 6250–200,000 patients. Conclusions This study proposes a novel, validated, and non-programming-based method for calculating Charlson and Elixhauser Comorbidity Index scores. As the comorbidity calculations can be conducted in Microsoft Excel’s simple graphical point-and-click interface, the new method lowers the threshold for calculating these two widely used indices. Trial registration retrospectively registered.

Connecting Mathematics and Science in Primary School STEM Education: Modeling the Population Growth of Species

In this research, we explored the potential of using a research-based teaching and learning sequence to promote pupils’ engagement in practices that are coherent with those of real world mathematical and scientific activity. This STEM (Science, Technology, Engineering and Mathematis) sequence was designed and implemented by pre-service teachers and science and mathematics education researchers with the aim of modeling the growth of a real population of rabbits. Results show explicit evidence of pupils’ engagement in relevant mathematical and scientific practices, as well as detailed descriptions of mathematical connections that emerged from those practices. We discuss how these practices and connections allowed the progressive construction of models, and the implications that this proposal may have for STEM task design and for the analysis of extra-mathematical connections.

Results from Canton Grisons of Switzerland Suggest Repetitive Testing Reduces SARS-CoV-2 Incidence (February-March 2021)

In February 2021, in response to emergence of more transmissible SARS-CoV-2 virus variants, the Canton Grisons launched a unique RNA mass testing program targeting the labour force in local businesses. Employees were offered weekly tests free of charge and on a voluntary basis. If tested positive, they were required to self-isolate for ten days and their contacts were subjected to daily testing at work. Thereby, the quarantine of contact persons could be waved. Here, we evaluate the effects of the testing program on the tested cohorts. We examined 121'364 test results from 27'514 participants during February-March 2021. By distinguishing different cohorts of employees, we observe a noticeable decrease in the test positivity rate and a statistically significant reduction in the associated incidence rate over the considered period. The reduction in the latter ranges between 18\%-50\%. The variability is partly explained by different exposures to exogenous infection sources (e.g., contacts with visiting tourists or cross-border commuters). Our analysis provides the first empirical evidence that applying repetitive mass testing to a real population over an extended period of time can prevent spread of COVID-19 pandemic. However, to overcome logistic, uptake, and adherence challenges it is important that the program is carefully designed and that disease incursion from the population outside of the program is considered and controlled.

A population-based controlled experiment assessing the epidemiological impact of digital contact tracing

While Digital contact tracing (DCT) has been argued to be a valuable complement to manual tracing in the containment of COVID-19, no empirical evidence of its effectiveness is available to date. Here, we report the results of a 4-week population-based controlled experiment that took place in La Gomera (Canary Islands, Spain) between June and July 2020, where we assessed the epidemiological impact of the Spanish DCT app Radar Covid. After a substantial communication campaign, we estimate that at least 33% of the population adopted the technology and further showed relatively high adherence and compliance as well as a quick turnaround time. The app detects about 6.3 close-contacts per primary simulated infection, a significant percentage being contacts with strangers, although the spontaneous follow-up rate of these notified cases is low. Overall, these results provide experimental evidence of the potential usefulness of DCT during an epidemic outbreak in a real population.

Simulation of pandemics in real cities: enhanced and accurate digital laboratories

This study develops a modelling framework for simulating the spread of infectious diseases within real cities. Digital copies of Birmingham (UK) and Bogotá (Colombia) are generated, reproducing their urban environment, infrastructure and population. The digital inhabitants have the same statistical features of the real population. Their motion is a combination of predictable trips (commute to work, school, etc.) and random walks (shopping, leisure, etc.). Millions of individuals, their encounters and the spread of the disease are simulated by means of high-performance computing and massively parallel algorithms for several months and a time resolution of 1 minute. Simulations accurately reproduce the COVID-19 data for Birmingham and Bogotá both before and during the lockdown. The model has only one adjustable parameter calculable in the early stages of the pandemic. Policymakers can use our digital cities as virtual laboratories for testing, predicting and comparing the effects of policies aimed at containing epidemics.

Assessing the Significance of Model Selection in Ecology

Model Selection is a key part of many ecological studies, with Akaike’s Information Criterion (AIC) being by far the most commonly used technique for this purpose. Typically, a number of candidate models are defined a priori and ranked according to their expected out-of-sample performance. Model selection, however, only assesses the relative performance of the models and, as pointed out in a recent paper, a large proportion of ecology papers that use model selection do not assess the absolute fit of the ‘best’ model. In this paper, it is argued that assessing the absolute fit of the ‘best’ model alone does not go far enough. This is because a model that appears to perform well under model selection is also likely to appear to perform well under measures of absolute fit, even when there is no predictive value. A model selection permutation test is proposed that assesses the probability that the model selection statistic of the ‘best’ model could have occurred by chance alone, whilst taking account of dependencies between the models. It is argued that this test should always be performed as a part of formal model selection. The test is demonstrated on two real population modelling examples of ibex in northern Italy and wild reindeer in Norway.

Current state of nesting settlements and study of great snipe Gallinago media in western Ukraine

In the paper, we describe the state of knowledge of the Great Snipe population in Western Ukraine since 19 century. Almost to the middle of the XX century, the state of knowledge about this species and the size of the surveyed territory, especially within the borders of Western Polissia, were considered as insufficient. This was caused by the cryptic behavior of the species, its nocturnal activity, and generally by low population size and ra­rity. We analyzed a significant amount of ornithological resources devoted to observations of Great Snipe in Western Ukraine, which indicate historically low population size and scarcity of distribution of the species in the study area. According to the literature sources, studies of Great snipe were somewhat intensified in the XX century. At the same time, different authors pointed out drainage works in the Polissia area, as a negative factor that drives the decrease in Great Snipe numbers in the area. or even caused complete extinction in some regions. The main range of the species in the area was still localized in the Polissian part of Volyn and Rivne regions, especially in valleys of Prypiat, Turia, Tsyr and Lva rivers. At the end of XX and the beginning of XXI intensive studies of Great Snipe were conducted on the territory of Shatsk National Nature Park, where during 10 years of studies, seasons with an increase of local population were reported, but in general negative tendency was detected and the proposal to include the species into the national red list was published. Our recent studies focused on the species, allowed us to discover new lekking places of Great Snipe. Therefore, the actual information on current numbers and distribution of the species in the region of Western Ukraine is presented. Besides leks, places of occasional observations are also mentioned, which increases the information load of the paper regar­ding the current distribution of the species in the western part of the country. The current population size is estimated as 100 lekking males, based on the total sum from all known leks. We suppose, that the real population size in the region of Western Ukraine can reach 150–200 lekking males.

Implementation and validation of a pooling strategy for a sustainable screening campaign for the presence of SARS-CoV-2.

Mass screening aimed at detecting, in asymptomatic subjects, the presence of SARS-CoV-2 is considered a strategic measure for the control of the present pandemic. It allows virus carriers to be identified and quarantined, thus preventing local spread and protecting vulnerable individuals. Although the screening strategy should be determined by the epidemiological situation, the size of the population that can be screened is indeed limited by the availability of resources. Here we present the implementation of an 8-sample pool strategy that relies on protocols, reagents and equipment currently used in clinical diagnostics. The method permitted to identify, with 100% sensitivity, specificity and accuracy, samples with low viral load, being the limit of detection of 11 viral copies extracted from the equivalent of 133ul of nasopharyngeal sample-pool. When the protocol has been applied, as a proof of principle, in a real population of 3592 consecutive nasopharyngeal swabs collected by healthcare providers in asymptomatic subjects, 20 positive pools were detected and in 100% of cases the positive specimens identified. Considering these performances, the 8-sample pool will allow, in populations with an expected positive rate of less than 1%, reducing costs by at least 80%, being a suitable method for a sustainable mass screening strategy in a population of asymptomatic subjects.

World crisis: paradoxes of analysis and scenario options for development

During the period of global crises, economists often form the belief that the current shocks are unique and after them “the world economy will no longer be the same”. At first glance, the current crisis gives every reason for similar generalizations. However, the analysis shows that both the crisis deployment mechanisms and the factors of its exacerbation demonstrate a high degree of continuity with previous episodes of crisis dynamics. This means that getting out of crisis will also be not a unique challenge, but a task closely linked to previous global experience of anti-crisis policy. Calculations show that the depth of the economic recession in the Russian Federation can be about one and a half times higher than the expected rate of decline in the global economy, and real population income in 2020 under a negative scenario can decrease by more than 10%. This means that the income support should become one of the top priorities of the anti-crisis policy in Russia. Ignoring it can not only make the crisis deeper but also bring give to problems in the socio-political sphere.

Hemophilia B — Mutation Rates and Incidence — A Simulation Study

The dynamics of rare X-linked recessive traits is explored by simulation. The model follows the prevalence of affected males and carrier females as separate but correlated variables. Different mutation rates and selection coefficients are introduced for males and females. A virtual population based on a published study of hemophilia B in the west of Scotland is followed at weekly intervals over many years. Speculative values of critical parameters to mimic the real population are proposed.