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Evaluating Generative Video AI for Standardized Psychiatric Patient Simulation With Graded Hygiene Deterioration.

Abstract Introduction: A clinician's initial assessment during the mental status examination (MSE) places substantial weight on a patient's general appearance, grooming, and hygiene. However, the logistical difficulty of producing simulated or standardized patient (SP) videos that systematically manipulate these characteristics limits the development of clinical AI tools and training curricula. This pilot study investigates the technical feasibility of using a video-generation diffusion model to re-animate modified reference images onto driving videos, enabling the creation of diverse patient presentations without the need for repeated filming. Methods: Utilizing an established publicly available dataset, we extracted reference images of three SPs and applied a text-to-image AI model to generate five appearance conditions: the unmodified baseline and four escalating hygiene-deterioration levels: mild, moderate, marked, and severe. We then used the Wan2.2-Animate-14B animate video generation AI model to re-animate these modified portraits onto the original driving footage. This factorial design varied several model parameters including; pose retargeting, classifier-free guidance scales, and generation modes, resulting in 180 unique videos. Quality was measured through Frechet Video Distance (FVD) for distributional fidelity and a physics-aware assessment performed by a multimodal large language model to evaluate physical plausibility. Results: Our analysis yielded two primary observations. First, compositing through replacement-mode achieved significantly higher temporal fidelity than animation-mode (mean FVD 8.6 vs. 19.4; Cohen's d = 1.84). Second, while distributional fidelity showed a monotonic decline as hygiene perturbation increased (Spearman rho = 0.48, p < 0.001), physics-aware scores did not follow a similar trend. This pattern is consistent with fine-motor artifacts arising from model-level generative constraints rather than from the severity of the appearance modification alone. Conclusions: These findings demonstrate that generating appearance-modulated clinical video libraries is technically achievable. Nevertheless, the persistence of fine-motor artifacts underscores the necessity of expert human oversight before these materials can be safely deployed in educational and translational settings. Keywords: Generative artificial intelligence; Standardized patients; Video diffusion models; Psychiatric simulation; Mental status examination; AI-generated video; Medical education; Digital psychiatry

Seasonality, source type, and women's water labor: A longitudinal mixed-methods study in Kenya and Honduras

Women shoulder the majority of water collection labor globally, yet how their water collection and water-related work experiences may change over time or by water source type remains insufficiently understood. We conducted a longitudinal, mixed-methods study in rural Kenya and Honduras to understand how women's experiences collecting water and performing water-related work varied between (a) two time points, (b) improved and unimproved water source types, and (c) water source location. Data were collected in 2023 and 2024 using interviews, observation, GPS-enabled watches, and scales to measure time and distance traveled, water weight and volume carried, and calories expended. 133 women participated in data collection (66 Kenya, 67 Honduras). We compared women's experience data by time point (2023 vs. 2024), source type (improved vs. unimproved), and source location (off-premises vs. on-premises) (t-test, Mann-Whitney U test). We also mapped participants' routes and activities to show which sources were visited, when, and for what activities. In Kenya, mean water collection time, distance, and caloric expenditure were significantly lower and water volume was significantly higher in 2024 when there were unexpected rains compared to 2023 when there was a persistent drought. When comparing source types during the 2023 drought, journeys to improved sources took significantly less time and energy and covered less distance than journeys to unimproved sources. These differences were not observed during the rainy conditions of 2024 when unimproved sources were closer and more accessible. In Honduras, water collection and water work burdens did not differ significantly by time point or source type. We found women with on-premises water access to still expend considerable time and caloric expenditure engaging in water work within their household compounds. Findings from Kenya suggest that water infrastructure improvements can reduce women's water collection burdens, though benefits may depend on and vary by season and source location. Findings from Honduras show that water labor does not end once water is in the household. Rather, substantial time and energy are expended carrying out water-related work even when sources are on premises, suggesting that efforts to assess water labor need to extend beyond collection alone. To meaningfully reduce burdens and ensure improved water sources are utilized during all seasons, initiatives need to consider source location, seasonal variability, and work beyond collection. Evaluations to assess infrastructure impacts on women's labor and well-being are needed and long overdue.

Evidence-guided AI regularization for suicidal ideation prediction in pediatric bipolar disorder

Background: Suicide prediction models in psychiatry often rely on purely data-driven feature selection, which can produce unstable and clinically opaque predictor sets in modest-sized samples. We developed Evidence-Based AI LASSO (EBAL), an evidence-guided regularization framework that incorporates curated clinical evidence into feature-specific penalty factors for interpretable prediction. Methods: Baseline data from 136 youth with confirmed bipolar spectrum disorder in the Greater Houston Area Bipolar Registry were analyzed using 20 candidate clinical predictors. Forty higher-level evidence documents on suicidality and related predictor domains were curated through a structured evidence synthesis workflow and indexed as an auditable evidence corpus. An open-weight large language model assigned feature-specific penalty factors using a prespecified scoring rubric, and these penalties were used to fit a weighted LASSO model. EBAL was compared with a standard evidence-agnostic LASSO using nested leave-one-out cross-validation. Results: For suicidal ideation, EBAL achieved an AUROC of 0.768, balanced accuracy of 0.757, sensitivity of 0.758, and specificity of 0.757. The standard LASSO achieved an AUROC of 0.760 and balanced accuracy of 0.715. EBAL improved balanced accuracy (+0.042, p=0.010) and Matthews correlation coefficient (+0.079, p=0.010), while retaining fewer stable predictors than standard LASSO (11/20 vs 18/20). The strongest positive predictors were current depressed mood, duration of mood disorder illness, and comorbid generalized anxiety disorder. For suicidal behavior, both models performed near chance and retained all candidate predictors. Limitations: The study was cross-sectional, single-site, and modest in sample size, with no external validation cohort. Conclusions: EBAL produced a sparser and more clinically coherent model for suicidal ideation in pediatric bipolar disorder, but did not improve prediction of suicidal behavior. These findings support evidence-guided regularization as a transparent strategy for aligning psychiatric prediction models with prior clinical knowledge while preserving interpretability.

Higher Population Coverage with Typhoid Conjugate Vaccine is Needed to Induce Herd Protection: Evidence from a Cluster-Randomized Trial in Urban Bangladesh

Introduction: A cluster randomized trial (CRT) in Bangladesh found that Vi-tetanus toxoid (Vi-TT) vaccine conferred 85% protection to vaccinees at 18 months of follow-up; however, it failed to confer significant herd protection to non-vaccinees. Methods: In the CRT, children aged 9 months to