Is a picture worth a thousand words: an analysis of the difficulty and discrimination parameters of illustrated vs. text-alone vignettes in histology multiple choice questions.

Background Advances in cognitive load theory have led to greater understanding of how we process verbal and visual material during learning, but the evidence base with regard to the use of images within written assessments is still sparse. This study examines whether the inclusion of images within the stimulus format of multiple choice questions (MCQs) has a predictable or consistent influence on psychometric item properties, such as difficulty or discrimination. Methods Item analysis data from three consecutive years of histology multiple choice examinations were included in this study. All items were reviewed and categorised according to whether their stem, or stimulus format, was purely textual or included an associated image. Results A total of 195 MCQs were identified for inclusion and analysed using classical test theory; 95 used text alone and 100 included an image within the question stem. The number of students per examination ranged from 277 to 347, with a total of 60,850 student-question interactions. We initially examined whether the inclusion of an image within the item stem altered the item difficulty using Mann–Whitney U. The median item difficulty for images with purely textual stems was 0.77, while that for items incorporating an appropriate image was 0.80; this difference was not significant (0.77 vs. 0.80; p = 0.862, Mann–Whitney-U = 4818.5). Mean values showed that the Item Discrimination Index appeared unaffected by the inclusion of an image within the stem, and Item point biserial correlation also showed no difference in means between these two groups (Independent samples t-test; 2-tailed). Conclusion We demonstrate that the addition of illustrations within undergraduate histology Multiple Choice Question stems has no overall influence on item difficulty, or measures of item discrimination. We conclude that the use of images in this context is statistically uncritical, and suggest that their inclusion within item stems should be based upon the principles of constructive alignment. However, further research with respect to the effect of images within item stems on cognitive processing, particularly with regard to image complexity or type, would enable the development of more informed guidelines for their use

Is a picture worth a thousand words?

Background: It has previously been suggested that the use of illustrations in MCQs may have variable effects on individual items. This study examines the effect of illustrated questions, as opposed to pure text, to discern if any overall bias between the two formats is detectable. Summary of work: We reviewed 6 Histology MCQ papers from our Medical Junior Cycle. Classical test theory analysis was performed on all MCQs, which were then divided into two groups, those with associated images and those without. Summary of results: We analysed 195 single best answer MCQs; 100 with associated illustrations, 95 without. The number of students per examination ranged from 277 to 347, with a total of 60,850 student-question interactions. There was no difference in question difficulty between the two groups (0.800 vs. 0.770; p = 0.862, Mann-Whitney-U). The discriminating power of the questions, as measured by point biserial correlation, was also identical (0.315 vs. 0.300; p = 0.939; Independent t-test). Conclusions: We found no overall bias or effect on either item difficulty or discrimination resulting from the addition of illustrations. We suggest that illustrated questions, as with textual vignettes, may test a range of cognitive levels depending on how they are employed

Natural Law Institute Proceedings Vol. 3

https://scholarship.law.nd.edu/naturallaw_proceedings/1003/thumbnail.jp

Identifying gene network patterns and associated cellular immune responses in children with or without nut allergy

Background: Although evidence suggests that the immune system plays a key role in the pathophysiology of nut allergy, the precise immunological mechanisms of nut allergy have not been systematically investigated. The aim of the present study was to identify gene network patterns and associated cellular immune responses in children with or without nut allergy. Methods: Transcriptome profiling of whole blood cells was compared between children with and without nut allergy. Three genes were selected to be validated on a larger cohort of samples (n = 86) by reverse transcription-polymerase chain reactions (RT-qPCR). The composition of immune cells was inferred from the transcriptomic data using the CIBERSORTx algorithm. A co-expression network was constructed employing weighted gene co-expression network analysis (WGCNA) on the top 5000 most variable transcripts. The modules were interrogated with pathway analysis tools (InnateDB) and correlated with clinical phenotypes and cellular immune responses. Results: Proportions of neutrophils were positively correlated and CD4+ T-cells and regulatory T-cells (Tregs) were negatively correlated with modules of nut allergy. We also identified 2 upregulated genes, namely Interferon Induced With Helicase C Domain 1 (IFIH1), DNA damage-regulated autophagy modulator 1 (DRAM1) and a downregulated gene Zinc Finger Protein 512B (ZNF512B) as hub genes for nut allergy. Further pathway analysis showed enrichment of type 1 interferon signalling in nut allergy. Conclusions: Our findings suggest that upregulation of type 1 interferon signalling and neutrophil responses and downregulation of CD4+ T-cells and Tregs are features of the pathogenesis of nut allergy

Guidelines for implementation of cystic fibrosis newborn screening programs: Cystic Fibrosis Foundation workshop report

Newborn screening for cystic fibrosis offers the opportunity for early intervention and improved outcomes. This summary, resulting from a workshop sponsored by the Cystic Fibrosis Foundation to facilitate implementation of widespread high quality cystic fibrosis newborn screening, outlines the steps necessary for success based on the experience of existing programs. Planning should begin with a workgroup composed of those who will be responsible for the success of the local program, typically including the state newborn screening program director and cystic fibrosis care center directors. The workgroup must develop a screening algorithm based on program resources and goals including mechanisms available for sample collection, regional demographics, the spectrum of cystic fibrosis disease to be detected, and acceptable failure rates of the screen. The workgroup must also ensure that all necessary guidelines and resources for screening, diagnosis, and care be in place prior to cystic fibrosis newborn screening implementation. These include educational materials for parents and primary care providers; systems for screening and for providing diagnostic testing and counseling for screen-positive infants and their families; and protocols for care of this unique population. This summary explores the benefits and risks of various screening algorithms, including complex situations that can occur involving unclear diagnostic results, and provides guidelines and sample materials for state newborn screening programs to develop and implement high quality screening for cystic fibrosis

Global Carbon Budget 2022

Accurate assessment of anthropogenic carbon dioxide (CO$_2$) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate is critical to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe and synthesize data sets and methodologies to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO$_2$ emissions (E$_{FOS}$) are based on energy statistics and cement production data, while emissions from land-use change (E$_{LUC}$), mainly deforestation, are based on land use and land-use change data and bookkeeping models. Atmospheric CO$_2$ concentration is measured directly, and its growth rate (G$_{ATM}$) is computed from the annual changes in concentration. The ocean CO$_2$ sink (S$_{OCEAN}$) is estimated with global ocean biogeochemistry models and observation-based data products. The terrestrial CO$_2$ sink (S$_{LAND}$) is estimated with dynamic global vegetation models. The resulting carbon budget imbalance (B$_{IM}$), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as ±1σ. For the year 2021, E$_{FOS}$ increased by 5.1 % relative to 2020, with fossil emissions at 10.1 ± 0.5 GtC yr$^{−1}$ (9.9 ± 0.5 GtC yr$^{−1}$ when the cement carbonation sink is included), and E$_{LUC}$ was 1.1 ± 0.7 GtC yr$^{−1}$, for a total anthropogenic CO$_2$ emission (including the cement carbonation sink) of 10.9 ± 0.8 GtC yr$^{−1}$ (40.0 ± 2.9 GtCO$_2$). Also, for 2021, G$_{ATM}$ was 5.2 ± 0.2 GtC yr$^{−1}$ (2.5 ± 0.1 ppm yr$^{−1}$), S$_{OCEAN}$ was 2.9  ± 0.4 GtC yr$^{−1}$, and S$_{LAND}$ was 3.5 ± 0.9 GtC yr$^{−1}$, with a B$_{IM}$ of −0.6 GtC yr$^{−1}$ (i.e. the total estimated sources were too low or sinks were too high). The global atmospheric CO$_2$ concentration averaged over 2021 reached 414.71 ± 0.1 ppm. Preliminary data for 2022 suggest an increase in E$_{FOS}$ relative to 2021 of +1.0 % (0.1 % to 1.9 %) globally and atmospheric CO$_2$ concentration reaching 417.2 ppm, more than 50 % above pre-industrial levels (around 278 ppm). Overall, the mean and trend in the components of the global carbon budget are consistently estimated over the period 1959–2021, but discrepancies of up to 1 GtC yr$^{−1}$ persist for the representation of annual to semi-decadal variability in CO$_2$ fluxes. Comparison of estimates from multiple approaches and observations shows (1) a persistent large uncertainty in the estimate of land-use change emissions, (2) a low agreement between the different methods on the magnitude of the land CO$_2$ flux in the northern extratropics, and (3) a discrepancy between the different methods on the strength of the ocean sink over the last decade. This living data update documents changes in the methods and data sets used in this new global carbon budget and the progress in understanding of the global carbon cycle compared with previous publications of this data set. The data presented in this work are available at https://doi.org/10.18160/GCP-2022 (Friedlingstein et al., 2022b)