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	<title>ordinal regression &#8211; Science</title>
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	<title>ordinal regression &#8211; Science</title>
	<link>https://scienmag.com</link>
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		<title>Pharmacy Students Report Stronger HIV and PrEP Training Than Medical Peers, Survey Finds</title>
		<link>https://scienmag.com/pharmacy-students-report-stronger-hiv-and-prep-training-than-medical-peers-survey-finds/</link>
		
		<dc:creator><![CDATA[Courtney Benton]]></dc:creator>
		<pubDate>Mon, 05 Oct 2026 15:20:53 +0000</pubDate>
				<category><![CDATA[Science Education]]></category>
		<category><![CDATA[cross-sectional study]]></category>
		<category><![CDATA[cross-sectional study on health student HIV education]]></category>
		<category><![CDATA[curriculum]]></category>
		<category><![CDATA[disparities in HIV and PrEP training]]></category>
		<category><![CDATA[gender differences in HIV training]]></category>
		<category><![CDATA[health communication]]></category>
		<category><![CDATA[health professions education]]></category>
		<category><![CDATA[healthcare professional preparedness for HIV prevention]]></category>
		<category><![CDATA[HIV and PrEP curriculum coverage]]></category>
		<category><![CDATA[HIV prevention]]></category>
		<category><![CDATA[HIV prevention training gaps]]></category>
		<category><![CDATA[HIV risk education in health schools]]></category>
		<category><![CDATA[impact of professional track on HIV education]]></category>
		<category><![CDATA[improving HIV training in health professional programs]]></category>
		<category><![CDATA[Medical Education]]></category>
		<category><![CDATA[medical students]]></category>
		<category><![CDATA[New York State]]></category>
		<category><![CDATA[ordinal regression]]></category>
		<category><![CDATA[pharmacy students]]></category>
		<category><![CDATA[pharmacy versus medical student HIV knowledge]]></category>
		<category><![CDATA[pre-exposure prophylaxis]]></category>
		<category><![CDATA[PrEP]]></category>
		<category><![CDATA[PrEP education in health professional curricula]]></category>
		<category><![CDATA[public health implications of HIV training disparities]]></category>
		<guid isPermaLink="false">https://scienmag.com/?p=238552</guid>

					<description><![CDATA[A survey of 385 New York medical and pharmacy students found that pharmacy trainees and senior students reported significantly more HIV and PrEP education than medical students and first-years, while cisgender women reported the least.]]></description>
										<content:encoded><![CDATA[<p>A new cross-sectional study of future health professionals in New York State suggests that the classroom pipeline feeding the next generation of HIV prevention providers may be leakier than public health goals demand. Researchers surveyed 385 medical and pharmacy students between November 2022 and January 2023, asking them how much education about HIV and about pre-exposure prophylaxis, or PrEP, they believed they had received during their academic training. The results, published in BMC Medical Education, reveal a striking pattern: while most students recalled some discussion of HIV risk, a substantial minority reported little or no exposure to PrEP content at all, and the depth of training varied dramatically depending on the student&#8217;s professional track, year of study, and gender.</p>
<p>The headline numbers frame the problem clearly. Overall, 71.95 percent of participants reported that HIV risk had been discussed during their training, and 64.42 percent said the same about PrEP. On the surface, those figures might seem encouraging, given that PrEP is a relatively recent addition to the prevention toolkit compared with decades of HIV education. But the study&#8217;s authors argue that the roughly one in three students who reported no PrEP discussion represents a missed opportunity at scale, because these are precisely the clinicians and pharmacists who will soon be prescribing, dispensing, and counseling patients about the medication that can reduce the risk of acquiring HIV through sex by about 99 percent when taken as directed.</p>
<p>The most eye-catching contrast in the data emerged between the two professional programs. After adjusting for other variables in multivariable ordinal regression models, pharmacy students had roughly twice the odds of medical students of reporting greater perceived HIV education, with an adjusted odds ratio of 2.03 and a 95 percent confidence interval of 1.35 to 3.04. The gap widened further for PrEP: pharmacy students had 3.41 times the odds of their medical counterparts of reporting greater perceived PrEP education, with a confidence interval of 2.23 to 5.22. That pharmacy trainees outpace medical trainees on PrEP awareness is notable, because physicians are often the ones expected to initiate PrEP prescriptions, while pharmacists increasingly serve as accessible touchpoints for medication counseling and, in many jurisdictions, direct pharmacy-based PrEP access.</p>
<p>The researchers also found that perceived education climbed steeply with academic seniority. Compared with first-year students, second-year students had nearly five times the odds of reporting greater perceived HIV education, with an adjusted odds ratio of 4.97, and more than five times the odds for PrEP education, at 5.42. Third-year students showed the strongest HIV signal in the entire analysis, with an adjusted odds ratio of 10.23, and fourth-year and beyond students reported the highest perceived PrEP education of all, with an adjusted odds ratio of 10.87. The trajectory makes intuitive sense: clinical content typically intensifies as students move from foundational coursework into rotations and experiential training. Yet the authors note that the pattern also implies first-year students, a group that includes many trainees who may already be interacting with peers and communities at risk, are largely entering professional school without meaningful PrEP literacy.</p>
<p>One of the more unexpected findings concerned gender. Cisgender women had lower odds than cisgender men of reporting greater perceived HIV education, with an adjusted odds ratio of 0.62, and lower odds of reporting greater perceived PrEP education, with an adjusted odds ratio of 0.51. In other words, even after accounting for program type and year of study, women in these cohorts consistently perceived less HIV and PrEP content in their training. The study did not test explanations for this disparity, but the finding raises questions about whether curricula, case materials, or classroom dynamics differ in ways that shape how students absorb and recall prevention content, and it flags a potential equity issue within the training environment itself.</p>
<p>Methodologically, the study relied on a cross-sectional survey design, which captures a snapshot of perceptions at a single point in time rather than tracking students longitudinally. The outcome measure was perceived education, meaning students&#8217; own recollection and assessment of how much HIV and PrEP content they had encountered, not an objective audit of curriculum hours or a test of knowledge. Perception-based measures are valuable because they reflect what students feel prepared to act on, which influences whether future clinicians will raise prevention topics with patients. At the same time, the authors acknowledge that perception may not perfectly mirror actual curricular content, and the single-state sample of 385 students limits generalizability to other regions or professional programs.</p>
<p>The statistical approach deserves attention for readers who follow epidemiological methods. The team first used bivariate analyses to examine group differences in perceived education, then built multivariable ordinal regression models to estimate adjusted odds ratios with 95 percent confidence intervals. Ordinal regression is appropriate here because the perceived education outcome is ordered rather than binary, allowing the models to estimate how each predictor shifts a student&#8217;s position along a graded scale of reported educational exposure. The confidence intervals reported throughout the results exclude the null value of one, indicating that the associations between program type, academic year, gender, and perceived education were statistically reliable in this sample.</p>
<p>Why does this matter for public health? PrEP has been available in the United States since 2012, and federal initiatives have set ambitious targets for expanding its uptake, particularly among communities most likely to benefit, including gay and bisexual men, Black and Latino communities, people who inject drugs, and individuals in the American South and other high-burden regions. Yet uptake has lagged far behind eligibility, and a frequently cited barrier is that potential prescribers themselves feel unprepared to discuss or initiate PrEP. Studies like this one point to the upstream end of that pipeline: if a third of medical and pharmacy students report never discussing PrEP during training, the shortfall in confident prescribers and counselors is being manufactured years before those graduates see their first patients.</p>
<p>The pharmacy finding cuts both ways. On one hand, it suggests pharmacy curricula have integrated HIV prevention content relatively well, perhaps reflecting the profession&#8217;s central role in medication management and the growth of pharmacist-delivered preventive services. On the other hand, it highlights an asymmetry in which the professionals most likely to write initial PrEP prescriptions report less preparation than those most likely to fill and monitor them. Expanding pharmacy-based PrEP access, which several states now permit, could partially compensate, but the study&#8217;s authors argue that medical education also needs strengthening so that the two professions can function as a coordinated prevention workforce rather than an unevenly trained one.</p>
<p>The research team, led by Jacob Bleasdale and Emily Carter of the University of Central Florida, with colleagues at the University at Buffalo including Amy Hequembourg, Gene D. Morse, and Sarahmona Przybyla, framed their conclusions as an invitation to curriculum designers rather than an indictment of any single program. Their stated goal is to address the variability in educational experiences they documented and to better prepare future health professionals to care for the communities most likely to benefit from PrEP. The work was supported by the National Center for Advancing Translational Sciences of the National Institutes of Health, with additional support to the lead author from the National Institute on Alcohol Abuse and Alcoholism. As PrEP formulations expand from daily oral tablets to longer-acting injectables, the educational demands on trainees will only grow, making the gaps identified here a moving target that curricula will need to chase deliberately rather than assume will close on its own.</p>
<p><strong>Subject of Research:</strong> Perceived HIV and PrEP education among medical and pharmacy students</p>
<p><strong>Article Title:</strong> Perceived HIV and PrEP education among medical and pharmacy students: a cross-sectional study</p>
<p><strong>Article References:</strong> Bleasdale, J., Carter, E., Hequembourg, A., Morse, G. D., &amp; Przybyla, S. (2026). Perceived HIV and PrEP education among medical and pharmacy students: a cross-sectional study. <em>BMC Medical Education</em>. <a href="https://doi.org/10.1186/s12909-026-10526-x" rel="noopener noreferrer">https://doi.org/10.1186/s12909-026-10526-x</a></p>
<p><strong>Image Credits:</strong> AI Generated</p>
<p><strong>DOI:</strong> <a href="https://doi.org/10.1186/s12909-026-10526-x" rel="noopener noreferrer">10.1186/s12909-026-10526-x</a></p>
<p><strong>Keywords:</strong> HIV prevention, PrEP, medical education, pharmacy students, medical students, cross-sectional study, health professions education, pre-exposure prophylaxis, curriculum, New York State, ordinal regression, health communication</p>
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		<post-id xmlns="com-wordpress:feed-additions:1">238552</post-id>	</item>
		<item>
		<title>New Decision Framework Peers Inside the Classes Machines Already Sort</title>
		<link>https://scienmag.com/new-decision-framework-peers-inside-the-classes-machines-already-sort/</link>
		
		<dc:creator><![CDATA[Denise Maddox]]></dc:creator>
		<pubDate>Fri, 02 Oct 2026 22:16:07 +0000</pubDate>
				<category><![CDATA[Technology and Engineering]]></category>
		<category><![CDATA[advancements in machine learning research]]></category>
		<category><![CDATA[applications in healthcare and finance]]></category>
		<category><![CDATA[attribute reduction]]></category>
		<category><![CDATA[classification]]></category>
		<category><![CDATA[decision frameworks for classification]]></category>
		<category><![CDATA[decision-making]]></category>
		<category><![CDATA[decision-making under class heterogeneity]]></category>
		<category><![CDATA[feature selection]]></category>
		<category><![CDATA[future state prediction in machine learning]]></category>
		<category><![CDATA[granular computing]]></category>
		<category><![CDATA[importance of within-class differences]]></category>
		<category><![CDATA[improvements in classification accuracy]]></category>
		<category><![CDATA[intra-class heterogeneity]]></category>
		<category><![CDATA[Intra-class heterogeneity in machine learning]]></category>
		<category><![CDATA[limitations of binary classifiers]]></category>
		<category><![CDATA[Machine learning]]></category>
		<category><![CDATA[multi-level decision analysis]]></category>
		<category><![CDATA[ordinal regression]]></category>
		<category><![CDATA[risk assessment in classification]]></category>
		<category><![CDATA[risk stratification]]></category>
		<category><![CDATA[rough sets]]></category>
		<category><![CDATA[structural proximity]]></category>
		<category><![CDATA[structure-enhanced ordered decision models]]></category>
		<category><![CDATA[weighted neighborhood rough sets]]></category>
		<guid isPermaLink="false">https://scienmag.com/?p=229307</guid>

					<description><![CDATA[Researchers in China have developed a decision framework that combines weighted neighborhood rough sets with ordinal regression to reveal hidden structural differences among objects that conventional classifiers place in the same ordered category.]]></description>
										<content:encoded><![CDATA[<p>Every day, algorithms quietly sort the world into categories. A patient is flagged as low or high risk, a loan application is approved or denied, a piece of equipment is classified as healthy or failing. But a growing body of research argues that these binary and ordered verdicts hide something important: the fact that two objects placed in the same category can still be profoundly different from each other. A new study published in the International Journal of Machine Learning and Cybernetics tackles exactly this blind spot, proposing a decision framework that looks inside the classes that conventional classifiers treat as uniform.</p>
<p>The work, led by Qiang Bao and Bingzhen Sun of Xidian University in Xi&#8217;an, together with Lun Guo and Jin Ye of Anhui Polytechnic University, introduces what the authors call a structure-enhanced ordered decision framework. Its central premise is deceptively simple: even when a fixed feature space and a given decision structure assign two objects to the same discrete class, real differences remain between them. Those differences, known as intra-class heterogeneity, may not change an object&#8217;s category membership today, but they can shape the probability of future state transitions, the evolution of risk, or the priority a decision-maker should give to one case over another.</p>
<p>What makes the approach notable is that it extracts this finer-grained structure without demanding anything new from the data. No additional variables are collected, and no higher-resolution measurements are required. Instead, the framework re-examines information that is already present, using it to sharpen the granularity and effectiveness of classification. In settings such as medical risk stratification, where collecting more data is expensive and sometimes impossible, that constraint matters. The study positions itself as a way of moving from a limited information space toward an ordered picture of system states, squeezing more insight out of the same measurements.</p>
<p>The mathematical backbone of the framework is a pair of techniques that are combined in an unusual way. The first is the weighted neighborhood rough set, or WNRS, an extension of the rough set theory first developed by the Polish computer scientist Zdzisław Pawlak in the 1980s. Classical rough sets deal with indiscernibility: objects that cannot be distinguished by the available attributes are lumped together into equivalence classes. Neighborhood rough sets relax this idea for real-world data, grouping objects that lie within a defined distance of one another rather than requiring exact matches. This makes the machinery suitable for continuous and mixed-attribute spaces, where measurements rarely coincide exactly.</p>
<p>The weighting added in this study gives the neighborhood structure a further layer of sophistication. By assigning different importance to different attributes, the method performs dependency analysis that supports attribute reduction, the task of discarding redundant or irrelevant features while preserving the decision-relevant structure of the data. The result of this stage is not merely a trimmed feature set. According to the authors, the weighted neighborhood relations induce a structured metric space, a geometric picture of the data in which distances between objects carry meaning for the decision problem at hand. That geometry becomes the raw material for everything that follows.</p>
<p>The second pillar of the framework is threshold-based ordinal logistic regression, a statistical method designed for outcomes that have a natural order but no meaningful numerical spacing. Disease severity grades, credit ratings, and damage scales all share this character: category two is worse than category one, but not necessarily by a fixed amount. Ordinal regression models the probability that an object falls at or above each threshold separating adjacent categories, respecting the order while avoiding the false precision of treating ranks as numbers. In the new framework, this regression supplies what the authors call individual proximity, a measure of how close each object sits to the decision boundaries that separate the ordered classes.</p>
<p>The genuine innovation lies in fusing these two views. The researchers introduce a novel structural proximity operator that integrates the individual proximity from the ordinal regression with the neighborhood relationships derived from the weighted neighborhood rough sets. The combined operator serves two purposes. First, it analyzes the sensitivity of individuals near the decision boundary, the cases for which a small change in measurement could flip the assigned category. Second, it quantifies the classification ability of individuals within the same ordered classes, revealing which members of a category are securely anchored and which are structurally marginal. Objects that are close in the metric space and share similar boundary proximity are treated as structurally related, even though the classifier has already placed them in the same box.</p>
<p>This dual consideration of proximity and neighborhood allows the framework to refine existing decision outcomes while preserving their ordered character. In practical terms, the method does not overturn the original classification; it layers a second, finer decision structure on top of it. A group of patients all labeled moderate risk, for example, could be differentiated into those whose profiles resemble the severe boundary and those who sit comfortably in the middle of the moderate range, informing which cases deserve earlier follow-up. The authors emphasize that this refinement is achieved within the existing information space, which is precisely the point: structure, not new data, is the resource being exploited.</p>
<p>To test the framework, the team conducted an empirical application on real-world data, reporting that the approach achieved further refinement of decision outcomes while maintaining the ordered structure of the results. The study arrives amid a broader surge of interest in granular computing, the research community that studies how knowledge can be represented at multiple levels of coarseness, and in rough-set-based feature selection, which has been applied to problems ranging from landslide susceptibility mapping to heterogeneous data analysis. It also connects to a parallel conversation in machine learning about classifiers with a reject option, systems that deliberately flag ambiguous cases rather than forcing them into a category. Sensitivity analysis near decision boundaries sits at the heart of both agendas.</p>
<p>The potential applications span domains where ordered outcomes dominate. Medical research has increasingly adopted ordinal models for disease grading and risk scoring, and systematic reviews of clinical prediction models highlight how sensitive conclusions can be to the treatment of ordered categories. Financial risk assessment, industrial maintenance scheduling, and environmental hazard rating all present the same structural challenge: the category is only the first question, and the second question, which cases within the category deserve attention first, is often the one with real consequences. A framework that answers both questions from the same data, without extra measurement cost, offers a pragmatic path for decision-makers working under information constraints.</p>
<p>The research also carries a conceptual message for the field of machine learning more broadly. Classification accuracy, long the headline metric of the discipline, says nothing about the internal structure of the classes it produces. As machine learning systems are entrusted with higher-stakes decisions in medicine, finance, and public policy, the demand is shifting from coarse labels toward ranked, risk-aware, and interpretable outputs. Frameworks like the one proposed by Bao and his colleagues suggest that the next gains may come not from bigger models or more data, but from smarter use of the geometry already latent in the feature space, turning the space between the categories into a source of knowledge rather than a gap the classifier simply jumps over.</p>
<p>For the researchers, the framework represents a new perspective on structure-enhanced decision-making, one that treats intra-class heterogeneity not as noise to be averaged away but as signal to be modeled. The work was supported by the Shaanxi National Funds for Distinguished Young Scientists, the National Natural Science Foundation of China, and an interdisciplinary exploration fund from Xidian University. Whether the approach will generalize across domains remains to be seen through further empirical testing, but its core idea, that the same data can support both a coarse ordered decision and a fine structural analysis, is likely to resonate wherever decisions are made with limited information and meaningful consequences.</p>
<p><strong>Subject of Research:</strong> A structure-enhanced ordered decision framework using weighted neighborhood rough sets and ordinal regression to characterize intra-class heterogeneity in ordered classification</p>
<p><strong>Article Title:</strong> A structure-enhanced ordered decision framework based on weighted neighborhood rough sets and ordinal regression</p>
<p><strong>Article References:</strong> A structure-enhanced ordered decision framework based on weighted neighborhood rough sets and ordinal regression. (n.d.). <a href="https://doi.org/10.1007/s13042-026-03302-2" rel="noopener noreferrer">https://doi.org/10.1007/s13042-026-03302-2</a></p>
<p><strong>Image Credits:</strong> AI Generated</p>
<p><strong>DOI:</strong> <a href="https://doi.org/10.1007/s13042-026-03302-2" rel="noopener noreferrer">10.1007/s13042-026-03302-2</a></p>
<p><strong>Keywords:</strong> machine learning, rough sets, weighted neighborhood rough sets, ordinal regression, attribute reduction, decision making, granular computing, intra-class heterogeneity, structural proximity, risk stratification, classification, feature selection</p>
]]></content:encoded>
					
		
		
		<post-id xmlns="com-wordpress:feed-additions:1">229307</post-id>	</item>
		<item>
		<title>Hidden Math Cap in AI Blood Cell Models Revealed by New Study</title>
		<link>https://scienmag.com/hidden-math-cap-in-ai-blood-cell-models-revealed-by-new-study/</link>
		
		<dc:creator><![CDATA[Blake Davidson]]></dc:creator>
		<pubDate>Fri, 02 Oct 2026 14:30:13 +0000</pubDate>
				<category><![CDATA[Technology and Engineering]]></category>
		<category><![CDATA[AI model interpretability in medical diagnostics]]></category>
		<category><![CDATA[artificial intelligence in clinical hematology]]></category>
		<category><![CDATA[automated blood count analysis]]></category>
		<category><![CDATA[blood cell classification]]></category>
		<category><![CDATA[blood smear review automation]]></category>
		<category><![CDATA[class imbalance]]></category>
		<category><![CDATA[compact neural networks for blood cell classification]]></category>
		<category><![CDATA[cumulative-link models]]></category>
		<category><![CDATA[cumulative-link ordinal model limitations]]></category>
		<category><![CDATA[deep learning]]></category>
		<category><![CDATA[hematology]]></category>
		<category><![CDATA[HemoCline]]></category>
		<category><![CDATA[HemoCline blood cell staging]]></category>
		<category><![CDATA[lightweight neural networks]]></category>
		<category><![CDATA[Machine learning]]></category>
		<category><![CDATA[machine learning failure modes]]></category>
		<category><![CDATA[Medical Imaging]]></category>
		<category><![CDATA[neural network optimization for blood cell analysis]]></category>
		<category><![CDATA[neutrophil maturation]]></category>
		<category><![CDATA[ordinal models in hematology]]></category>
		<category><![CDATA[ordinal regression]]></category>
		<category><![CDATA[rare blood cell detection challenges]]></category>
		<category><![CDATA[threshold dynamics]]></category>
		<guid isPermaLink="false">https://scienmag.com/?p=228259</guid>

					<description><![CDATA[Researchers have identified a mathematical probability ceiling in ordinal machine learning models that can silently suppress rare blood cell stages, and built a 532,000-parameter network that stages neutrophil maturation while mapping exactly where the ceiling binds and where it does not.]]></description>
										<content:encoded><![CDATA[<p>A tiny mathematical ceiling buried inside one of machine learning&#8217;s most trusted tools for ordered classification could quietly stop an artificial intelligence from ever recognizing the rarest, most dangerous cells in a blood sample. That is the central warning of a new open-access study published in Machine Learning with Applications, in which researchers dissect a failure mode of cumulative-link ordinal models and then build a compact neural network, called HemoCline, that stages white blood cell maturation with a fraction of the parameters used by today&#8217;s leading systems. The work arrives at a moment when automated hematology is under intense pressure: the complete blood count is the most frequently ordered laboratory test in clinical medicine, yet a large share of samples still trigger manual smear review, and most laboratories rely on human morphological assessment as the final arbiter.</p>
<p>The problem begins with a formulation that has served statistics well for more than four decades. Cumulative-link ordinal models, introduced by McCullagh in 1980, classify ordered categories by placing a latent score on an axis and slicing that axis with learned thresholds. The probability of landing in any interior category is computed as the difference of two sigmoid functions evaluated at adjacent thresholds. This elegant construction underpins the proportional odds model, the CORAL ordinal regression framework, and softplus-reparameterized variants used throughout deep learning, from age estimation to histopathological grading. But the researchers point out an elementary consequence that is rarely confronted in the deep learning era: the maximum probability achievable for any interior stage is bounded by the gap between its two neighboring thresholds. The bound is tight and has a closed form, Pmax(g) = 2σ(g/2) − 1, and it applies to every model built on this sigmoid-difference formulation.</p>
<p>The numbers make the danger vivid. When the threshold gap equals 1.0, an interior category can never exceed a probability of 0.245, meaning the argmax decision rule will almost never select it, no matter how powerful the network, how long the training, or how abundant the data. At a gap of 2.0 the ceiling rises to 0.462, and at roughly 3.0 it reaches 0.635. The ceiling is a property of the sigmoid parameterization itself, and the authors note that it was already known in the psychometrics literature on graded response models, where Samejima studied the same category response function in 1969. What classical item-response theory never addressed, however, is what happens when such parameters are estimated by stochastic gradient descent on severely imbalanced image batches rather than by maximum likelihood on balanced matrices.</p>
<p>That imbalance is exactly where the failure mode becomes acute. In clinical datasets of peripheral blood cells, mature segmented neutrophils outnumber early-stage myelocytes by ratios exceeding 100 to 1. The dominant endpoint class sits far above all interior thresholds on the latent axis, so it contributes essentially no gradient at the interior boundaries. Meanwhile, the rare interior samples that would push those thresholds apart are too few, and too poorly positioned early in training, to supply the restoring force. The result is a self-reinforcing feedback loop: narrow gaps keep interior stages hard to place, and misplaced interior samples keep the gaps narrow. The researchers derive the threshold gradients explicitly and show that a correctly positioned interior sample exerts a widening force that grows monotonically as the gap shrinks and diverges as the gap approaches zero, a restoring mechanism that can rescue a collapsing configuration once features become separable.</p>
<p>To test these predictions, the team built HemoCline, a convolutional network of just 532,131 parameters whose backbone is assembled from mobile inverted bottleneck blocks, the same efficient building blocks behind the MobileNet family. On top of this shared backbone sits a hierarchical classification head that routes cells through biologically motivated branches, mirroring the taxonomy of granulocytes, agranulocytes, red cell lineage, and platelets, and then classifies granulocyte maturation stages through a cumulative-link head with learnable, strictly ordered boundaries enforced by softplus reparameterization. The four modeled stages follow the well-characterized neutrophilic maturation sequence from myelocyte to metamyelocyte to band neutrophil to segmented neutrophil, with each transition marked by progressive nuclear condensation and lobulation that human annotators discretize into stages.</p>
<p>The experimental validation ran on two independent public datasets: the KU-Optofil dataset from Turkey, containing 31,489 images across 13 classes with a striking 167 to 1 imbalance between its largest and smallest maturation classes, and the Barcelona PBC dataset from Spain with 17,092 images across 8 classes. Trained entirely from scratch without ImageNet pretraining, HemoCline reached 98.86 percent macro-F1 on Barcelona and 93.36 percent accuracy on KU-Optofil&#8217;s harder 13-class task. Under an identical from-scratch recipe, it matched MobileNetV3-Small on accuracy with 2.9 times fewer parameters while exceeding it on macro-F1, maturation-chain F1, calibration, and seed-to-seed stability. Against the best-performing pretrained model of the original KU-Optofil benchmark, DenseNet-121 at 13 times the parameter count, HemoCline sits 1.9 percentage points lower on accuracy, a gap the authors attribute honestly to capacity rather than claiming parity.</p>
<p>Perhaps the most scientifically interesting results are the ones the authors report against their own expectations. The study pre-registered four hypotheses, and two were falsified. The Maturation Coordinate, the scalar output of the ordinal head, was predicted to form a smooth continuum correlating strongly with true stage; instead it converged to four separated clusters, with a Spearman correlation of just 0.30 against a pre-specified threshold of 0.75. Yet the clusters discriminate powerfully between adjacent stages, with Cliff&#8217;s delta reaching nearly perfect separation for the metamyelocyte-to-band transition. The model, in other words, learns to distinguish stages without interpolating between them. The second falsification concerned cross-laboratory transfer: adjusting only the learned thresholds on data from a new laboratory recovered 76.5 percent macro-F1, far short of the 91 percent achieved by retraining the full classification head, because branch and sub-head probabilities shift between laboratories just as the maturation boundary does.</p>
<p>The threshold dynamics themselves behaved as the gradient analysis predicted, but with a twist. Starting from a deliberately narrow initialization with a gap of 1.0, where the ceiling analysis predicts near-zero interior recall, the optimizer self-widened the gaps to an average of about 2.0 within 40 epochs, confirming the restoring-force mechanism. But the gap-floor regularizer the team derived from the closed-form minimum gap formula turned out to be inactive at the working initialization, where gaps already sat above the floor, and it failed to rescue a shortened training schedule. An ablation against CORN, an ordinal method that avoids the ceiling by construction, was statistically indistinguishable from the cumulative-link head across five seeds. The authors conclude that the ceiling is real and observable at narrow initializations, but that the correct response is a wider initialization and monitoring of gap trajectories rather than an added loss term, and they offer the closed-form minimum gap as a diagnostic grounded in the stage count rather than a grid search.</p>
<p>The study also distinguishes carefully between the two head configurations and what each is for. On aggregate metrics the flat, non-ordinal head matches or slightly beats the ordinal one, and it wins on agranulocyte separation, distinguishing lymphocytes from reactive lymphocytes and blasts more reliably. The ordinal head earns its place on the sub-task it was designed around: maturation-stage resolution improves, with quadratic weighted kappa rising from 0.815 to 0.877, and the hardest class, band neutrophil, shows three times lower seed-to-seed variability. The choice between them, the authors argue, is a choice about which errors a deployment can absorb. All configurations passed the team&#8217;s multi-seed deployment-readiness protocol, which trains five copies differing only in random seed and requires both low coefficient of variation and no seed below pre-committed performance floors.</p>
<p>The practical implications reach beyond hematology. The interior-stage bound applies to any model computing category probabilities as differences of sigmoid threshold terms, and the authors suggest that tasks with more ordinal stages, where the same latent axis must accommodate more boundaries and tighter gaps, are where the collapse phenomenon should matter most. For point-of-care devices operating under tight memory and latency budgets, a 532 K-parameter network that runs in under 2 milliseconds on CPU offers a credible alternative to the massive pretrained backbones that dominate the literature. The authors are candid about limitations: myelocyte classification remains poor for both configurations with only 68 training examples, the transfer analysis spans just two laboratories, and clinical deployment would require prospective validation and regulatory clearance. But as a demonstration that a small, biologically structured model can approach the accuracy of giants while exposing a hidden mathematical trap in the process, the work marks a compelling step toward AI that understands not just what a cell is, but where it sits along the road of its own maturation.</p>
<p><strong>Subject of Research:</strong> Threshold gap dynamics in cumulative-link ordinal models for imbalanced blood cell maturation classification</p>
<p><strong>Article Title:</strong> HemoCline: Threshold gap dynamics in cumulative-link ordinal models for imbalanced blood cell maturation</p>
<p><strong>Article References:</strong> Daga, M., Bommineni, K. R., &amp; Ramu, S. P. (2026). HemoCline: Threshold gap dynamics in cumulative-link ordinal models for imbalanced blood cell maturation. <em>Machine Learning with Applications, 26</em>, Article 101031. <a href="https://doi.org/10.1016/j.mlwa.2026.101031" rel="noopener noreferrer">https://doi.org/10.1016/j.mlwa.2026.101031</a></p>
<p><strong>Image Credits:</strong> AI Generated</p>
<p><strong>DOI:</strong> <a href="https://doi.org/10.1016/j.mlwa.2026.101031" rel="noopener noreferrer">10.1016/j.mlwa.2026.101031</a></p>
<p><strong>Keywords:</strong> ordinal regression, cumulative-link models, blood cell classification, class imbalance, neutrophil maturation, HemoCline, lightweight neural networks, hematology, deep learning, threshold dynamics, medical imaging, machine learning</p>
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		<title>Just One in Five Nigerian Women Get WHO-Recommended Eight Antenatal Visits</title>
		<link>https://scienmag.com/just-one-in-five-nigerian-women-get-who-recommended-eight-antenatal-visits/</link>
		
		<dc:creator><![CDATA[Harold Sullivan]]></dc:creator>
		<pubDate>Sat, 12 Sep 2026 19:44:31 +0000</pubDate>
				<category><![CDATA[Medicine]]></category>
		<category><![CDATA[Africa]]></category>
		<category><![CDATA[antenatal]]></category>
		<category><![CDATA[antenatal care]]></category>
		<category><![CDATA[antenatal care coverage in Nigeria]]></category>
		<category><![CDATA[Demographic and Health Survey]]></category>
		<category><![CDATA[global maternal health standards]]></category>
		<category><![CDATA[health inequalities]]></category>
		<category><![CDATA[health services research]]></category>
		<category><![CDATA[healthcare system shortcomings Nigeria]]></category>
		<category><![CDATA[impact of antenatal visit frequency]]></category>
		<category><![CDATA[increasing antenatal care compliance]]></category>
		<category><![CDATA[Inequalities]]></category>
		<category><![CDATA[Maternal health]]></category>
		<category><![CDATA[maternal health challenges Nigeria]]></category>
		<category><![CDATA[maternal health services]]></category>
		<category><![CDATA[maternal mortality risk factors]]></category>
		<category><![CDATA[Nigeria]]></category>
		<category><![CDATA[Nigeria Demographic and Health Survey 2024]]></category>
		<category><![CDATA[ordinal regression]]></category>
		<category><![CDATA[pregnancy complication detection]]></category>
		<category><![CDATA[pregnancy healthcare access Nigeria]]></category>
		<category><![CDATA[sub-Saharan Africa maternal health]]></category>
		<category><![CDATA[WHO antenatal visit recommendations]]></category>
		<category><![CDATA[WHO guidelines]]></category>
		<guid isPermaLink="false">https://scienmag.com/?p=198048</guid>

					<description><![CDATA[A national analysis of Nigerian survey data shows only 17 percent of pregnant women meet the WHO's eight-contact antenatal care standard, with education, wealth, and region driving steep inequalities.]]></description>
										<content:encoded><![CDATA[<p>Nigeria remains one of the most dangerous places in the world to give birth, and a new nationally representative study has quantified just how far the country&#8217;s pregnant women are falling short of international standards for prenatal care. Analyzing data from the 2024 Nigeria Demographic and Health Survey, researchers found that 28 percent of women received no antenatal care at all during their most recent pregnancy, while only 17 percent reached the eight or more contacts that the World Health Organization now recommends. The findings, published in BMC Health Services Research, reveal a health system in which even the older, less demanding benchmark of four visits remains out of reach for nearly half of expectant mothers.</p>
<p>The World Health Organization originally advised pregnant women to attend at least four antenatal visits, a target that shaped maternal health programming across sub-Saharan Africa for decades. In 2016, however, the organization overhauled its guidance, replacing the four-visit model with a recommendation of eight or more individual contacts with a health provider over the course of pregnancy. The change reflected growing evidence that more frequent contact allows clinicians to detect complications such as preeclampsia, anemia, and fetal growth restriction earlier, and to intervene before they become fatal. The revised standard also shifted the language from &#8216;visits&#8217; to &#8216;contacts&#8217; to emphasize that every interaction between a pregnant woman and her health system matters.</p>
<p>Most research on antenatal care in Nigeria has relied on a binary measure, simply asking whether a woman attended any sessions at all or at least four. That approach, the study&#8217;s authors argue, obscures how far along the care continuum women actually progress and makes it impossible to track national movement toward the current WHO guideline. To close that gap, the research team from Obafemi Awolowo University and Federal University Birnin Kebbi categorized utilization into three ordered levels: fewer than four visits, four to seven visits, and eight or more visits. This ordinal framework allowed them to simultaneously evaluate adherence to both the old and new WHO benchmarks and to identify which factors push women across each successive threshold.</p>
<p>The data set covered women aged 15 to 49 who had at least one live birth in the reference period, a nationally representative sample designed to reflect Nigeria&#8217;s enormous demographic and geographic diversity. The descriptive results alone paint a sobering picture. Among all women surveyed, 47 percent reported fewer than four antenatal visits for their most recent pregnancy, 36 percent reported four to seven visits, and a mere 17 percent attained eight or more contacts. Combined with the 28 percent who received no care whatsoever, the figures mean that fewer than one in five Nigerian pregnancies currently meet the international standard that global health authorities consider the minimum for protecting maternal and newborn lives.</p>
<p>To understand who reaches each level of care, the researchers employed a generalized ordered logistic regression model, a statistical technique suited to outcomes that fall along a natural hierarchy. Unlike a standard logistic regression that collapses the outcome into two categories, the generalized ordered model estimates how each sociodemographic factor relates to crossing each cumulative threshold, from no care to any care, from minimal to adequate care, and from adequate to the full WHO-recommended schedule. The model adjusted for a battery of confounders, and design-based chi-square tests were first used to confirm that utilization varied significantly across social and regional strata in the raw data.</p>
<p>Education emerged as one of the most powerful predictors of care. Women with higher education had more than five times the odds of achieving at least four antenatal visits compared with their less-educated counterparts, with an adjusted odds ratio of 5.33 and a 95 percent confidence interval of 4.26 to 6.66. Wealth told a similar but distinct story. Women in the richest households were more than four times as likely as the poorest to reach eight or more contacts, with an adjusted odds ratio of 4.38 and a confidence interval of 3.34 to 5.74. Intriguingly, the factors that help women cross the four-visit threshold are not always the same factors, or of the same magnitude, that carry them to the eight-contact level, a nuance the binary analyses of previous studies could never reveal.</p>
<p>Geography proved to be perhaps the starkest divider of all. Nigeria&#8217;s South West region, home to Lagos and some of the country&#8217;s best-resourced health infrastructure, showed dramatically better outcomes than the North Central zone used as the reference. Women in the South West had nearly seven times the odds of attaining eight or more antenatal visits compared with their North Central counterparts, with an adjusted odds ratio of 6.91 and a 95 percent confidence interval of 5.74 to 8.31. The pattern reflects deep, long-standing inequalities between southern and northern Nigeria in educational attainment, health facility density, and the availability of skilled birth attendants, divisions that shape health outcomes long before a woman ever becomes pregnant.</p>
<p>The implications of these findings reach well beyond Nigerian borders. As low- and middle-income countries begin to realign their maternal health monitoring systems with the 2016 WHO guideline, Nigeria&#8217;s experience offers a warning about how much progress may be masked when success is defined as four visits rather than eight. A country that appears close to universal basic antenatal coverage under the old standard may, in truth, be serving only a small fraction of pregnant women at the level now considered necessary. The authors suggest that policies aimed at improving utilization must simultaneously tackle socioeconomic and regional inequality while strengthening the supply side, ensuring that facilities exist, are stocked, and are staffed close enough to home for women to complete the full contact schedule.</p>
<p>For the roughly seven million Nigerian women who give birth each year, the arithmetic of the study translates into a concrete risk. Antenatal care is a key determinant of maternal survival because it is the principal channel through which danger signs are detected, iron and tetanus prophylaxis are delivered, hypertension is managed, and women are connected to skilled delivery services. Nigeria already accounts for a disproportionate share of the world&#8217;s maternal deaths, and the new analysis suggests that the country&#8217;s path to reducing that toll runs through both classrooms and clinics. Raising female educational attainment, narrowing the wealth gap, and investing specifically in the underserved northern regions would, the evidence indicates, do more to lift women from a handful of visits to the full recommended schedule than any single clinical intervention.</p>
<p>The study also demonstrates the value of the ordinal analytical approach itself. By modeling antenatal utilization as a graded outcome aligned with both WHO eras of guidance, the researchers produced estimates that policymakers can act on at every point along the care continuum, identifying where women drop out and which characteristics distinguish those who persist. The dataset was drawn from the Demographic and Health Survey Program, whose anonymized, publicly accessible surveys are conducted with approval from national ethical review boards and the ICF Institutional Review Board, with informed consent obtained from all participants. The research received no specific external funding, and the authors declare no competing interests. As Nigeria and its neighbors grapple with the gap between the four-visit past and the eight-contact future, this analysis provides both the baseline measurement and the analytical roadmap for tracking, honestly and precisely, whether the world&#8217;s most vulnerable pregnant women are finally getting the care they were promised.</p>
<p><strong>Subject of Research:</strong> Sociodemographic and regional inequalities in antenatal care utilization in Nigeria relative to WHO guideline thresholds</p>
<p><strong>Article Title:</strong> Inequalities in antenatal care utilization in Nigeria: an ordinal analysis aligned with WHO guidelines</p>
<p><strong>Article References:</strong> Sani, J., Adesina, A. N., Awoniyi, A., Otitoju, O., Ajibade, T. O., Boboye, I., &amp; Bisiriyu, L. A. (2026). Inequalities in antenatal care utilization in Nigeria: an ordinal analysis aligned with WHO guidelines. <em>BMC Health Services Research</em>. <a href="https://doi.org/10.1186/s12913-026-15606-8" rel="noopener noreferrer">https://doi.org/10.1186/s12913-026-15606-8</a></p>
<p><strong>Image Credits:</strong> AI Generated</p>
<p><strong>DOI:</strong> <a href="https://doi.org/10.1186/s12913-026-15606-8" rel="noopener noreferrer">10.1186/s12913-026-15606-8</a></p>
<p><strong>Keywords:</strong> antenatal care, Nigeria, WHO guidelines, maternal health, health inequalities, ordinal regression, Demographic and Health Survey, maternal health services, health services research, Africa, Inequalities, antenatal</p>
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