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One-stage meta-analysis of individual participant data (IPD) poses several statistical and computational challenges. For time-to-event outcomes, the approach requires the estimation of complicated nonlinear mixed-effects models that are flexible enough to realistically capture the most important characteristics of the IPD. We present a model class that incorporates general normally distributed random effects into linear transformation models. We discuss extensions to model between-study heterogeneity in baseline risks and covariate effects and also relax the assumption of proportional hazards. Within the proposed framework, data with arbitrary random censoring patterns can be handled. The accompanying $\textsf{R}$ package tramME utilizes the Laplace approximation and automatic differentiation to perform efficient maximum likelihood estimation and inference in mixed-effects transformation models. We compare several variants of our model to predict the survival of patients with chronic obstructive pulmonary disease using a large data set of prognostic studies. Finally, a simulation study is presented that verifies the correctness of the implementation and highlights its efficiency compared to an alternative approach. [ABSTRACT FROM AUTHOR]

Purpose: To investigate feasibility, reliability and discriminative validity of pseudoisochromatic (PIC) colour vision tests, the Mollon–Reffin minimalist (MRM) test and the Cambridge Colour Test (CCT) among children (3–10 years) with reduced visual acuity. Methods: Thirty‐three patients with reduced visual acuity and 38 healthy control subjects with age‐related normal visual acuity were recruited for this prospective study. Visual acuity in patients was reduced due to amblyopia, binocular maculopathy, or optic neuropathy. Tests were performed in a single 1‐hr session. Results: All but two children successfully completed the PIC and MRM tests. Success rate for the CCT was lower, 87%, CI [72%, 96%] for control subjects and 79%, CI [61%, 91%] for patients, with a strong positive effect of age on the odds of successful completion (OR 5.63, p = 0.007). Reliability was high in PIC and MRM tests but comparably lower in CCT. The rate of correct answers in PIC tests was between 88% and 100%. One proband was diagnosed with deuteranomaly with an average Ishihara score of 21%. All children (with the exception of one daltonian) scored at least two points in the MRM test. Sensitivity thresholds in CCT decreased with age with a strong effect size in control subjects and weak to moderate effect size in patients. Conclusions: Pseudoisochromatic and MRM tests show sufficient feasibility in young children with reduced visual acuity. For CCT feasibility in 3–5‐year olds is reduced, most probably due to the longer test duration. Consistent with earlier findings, colour discrimination thresholds decrease with age independent on visual acuity status. [ABSTRACT FROM AUTHOR]

Background: Prior research suggests pollen allergies may be associated with cognitive function, although the effect sizes and specific cognitive outcomes varied across studies. With pollen seasons starting earlier and intensifying due to climate change, understanding the effects of pollen exposure on cognition is increasingly relevant. This study investigated the relationship between ambient pollen exposure and cognitive performance in Swiss adults., Methods: Four cognitive assessments were used to measure the daily performance of 392 participants (299 with pollen allergies) over a 10-day period during pollen season. We used generalized additive mixed models to assess the exposure-response relationship between individualized pollen exposure and cognitive performance, as well as allergic symptom severity and cognitive performance, adjusting for individual characteristics and time-varying environmental and individual confounders (e.g., air pollution, weather, and coffee intake)., Results: We did not find any statistically significant relationships between pollen exposure or severity of allergic symptoms and overall score or reaction time on tests of response inhibition, attention, and visual-spatial memory. We observed a 1% increase [95% confidence interval (CI) = 0.13%, 2.0%] in average reaction time on a test of grammatical reasoning for allergic participants at an exposure of 300 pollen/m 3 (12-hour average)., Conclusion: Overall, our study population did not exhibit changes in cognitive performance related to pollen exposure or perceived allergic symptoms. A marginal, but statistically significant effect on the response time of pollen-allergic individuals was observed for a test of verbal reasoning, however, this is likely to be a chance finding considering the number of exposures and outcomes evaluated., Competing Interests: The authors declare that they have no conflicts of interest with regard to the content of this report., (Copyright © 2025 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The Environmental Epidemiology. All rights reserved.)