Asymmetry models based on ordered score and separations of symmetry model for square contingency tables

Summary This study proposes two original asymmetry models based on ordered scores for square contingency tables with the same row and column ordinal classifications. The proposed models can be applied to cases in which the scores of all categories are known or unknown. In the proposed models, the log odds for an observation falling in the (i, j)th cell instead of the (j, i)th cell are inversely proportional to the difference of the ordered scores corresponding to categories i and j. The asymmetry parameter of the proposed model can be useful for inferring whether the row variable is stochastically greater than the column variable or vice versa. The proposed models constantly hold when the symmetry model holds, but the converse is not necessarily true. This study also examines what is necessary for a model, in addition to the proposed models, to satisfy the symmetry model, and gives separations of the symmetry model using the proposed and marginal mean equality models. We apply real data to show the utility of the proposed models. The proposed models provide a better fit than that of the existing models.

Distal radius fractures – A volar plate is not just a volar plate

Introduction Increasingly complex distal radius plate designs are available for treating distal radius fractures. As a result, many fractures are being ‘over-treated’ with more complex volar plate designs than necessary. We hypothesise that significant cost savings could be made by rationalising the use of complex locking plate designs. Methods Over a two-year period, radiographs of 250 consecutive distal radius fractures fixed with volar locking plates were reviewed and the type of plate, and type and number of screws used for fixation were noted. Preoperative radiographs were independently reviewed to ascertain if it would have been possible to stabilise the fracture with a simpler, extra-articular plate design. Potential cost savings were then calculated. Results It was deemed that 89 (36.5%) of the 250 cases originally treated with a more complex 2 column variable angle plate could have been treated with an extra-articular construct, leading to potential savings of £19,224. Conclusion It is clear from our data that many distal radius fracture patterns are being ‘over-treated’ with complex locking plate designs with multiple rows of screws and that substantial cost savings could be made by selecting an appropriate construct to suit the fracture pattern.

pISA-tree: standard directory tree as a support for reproducible research

Basic idea of science is reproducibility of phenomena and experiments. Reproducibility of data analyses and reports is becoming more and more important. It requires structured organization of data, augmented with enought metadata for future re-use of data. Our aim is to provide a system to store data in a way that can be used for small and moderate size projects and fulfill minimal requirements of ISA-tab and FAIR paradigm. Standard directory trees are applicable to research data storage. The main condition is that information is organized in files and we are not interested in the system that enables access to individual line/record or column/variable in a tabular data structure in the file. The tree structure is generated on the fly by use of batch files (on Windows platform) that generate necessary folders and meta-data template files. We implemented the system of standard directory trees for support of the research in our research unit. Most often, our research projects can be hierarchically structured into, what can be called, Investigation which is composed of several Studies. Each individual study can have one or more Assays. To reflect this hierarchy, we named such directory tree the pISA-tree. To make new levels we provide three batch files: makeInvestigation, makeStudy, and makeAssay. Special attention is given to Description files that contain meta-information about research, protocols, samples, features et cetera. They are in line with the standards accepted for particular assays (e.g. MIQE, MIAMI, MIRIAM,...) which allow exchange of data with other data management services. In particular, we have in mind FAIRdom platform and some digital notebooks (e.g. SciNote). pISA-tree structure rely on directories that are readily available on any computer platform and familiar to use by the researchers. Since the translation of meta-data into ISA-tab standard format is not too complex, pISA-tree is a step towards the FAIR paradigm.

pISA-tree: standard directory tree as a support for reproducible research

Basic idea of science is reproducibility of phenomena and experiments. Reproducibility of data analyses and reports is becoming more and more important. It requires structured organization of data, augmented with enought metadata for future re-use of data. Our aim is to provide a system to store data in a way that can be used for small and moderate size projects and fulfill minimal requirements of ISA-tab and FAIR paradigm. Standard directory trees are applicable to research data storage. The main condition is that information is organized in files and we are not interested in the system that enables access to individual line/record or column/variable in a tabular data structure in the file. The tree structure is generated on the fly by use of batch files (on Windows platform) that generate necessary folders and meta-data template files. We implemented the system of standard directory trees for support of the research in our research unit. Most often, our research projects can be hierarchically structured into, what can be called, Investigation which is composed of several Studies. Each individual study can have one or more Assays. To reflect this hierarchy, we named such directory tree the pISA-tree. To make new levels we provide three batch files: makeInvestigation, makeStudy, and makeAssay. Special attention is given to Description files that contain meta-information about research, protocols, samples, features et cetera. They are in line with the standards accepted for particular assays (e.g. MIQE, MIAMI, MIRIAM,...) which allow exchange of data with other data management services. In particular, we have in mind FAIRdom platform and some digital notebooks (e.g. SciNote). pISA-tree structure rely on directories that are readily available on any computer platform and familiar to use by the researchers. Since the translation of meta-data into ISA-tab standard format is not too complex, pISA-tree is a step towards the FAIR paradigm.