GRADE Concept Paper 8: Judging the certainty of discrimination performance estimates of prognostic models in a body of validation studies.

BACKGROUND: Prognostic models incorporate multiple prognostic factors to estimate the likelihood of future events for individual patients based on their prognostic factor values. Evaluating these models crucially involves conducting studies to assess their predictive performance, like discrimination. Systematic reviews and meta-analyses of these evaluation studies play an essential role in selecting models for clinical practice. METHODS: In this paper, we outline three thresholds to determine the target for certainty rating in the discrimination of prognostic models, as observed across a body of validation studies. RESULTS AND CONCLUSION: We propose three thresholds when rating the certainty of evidence about a prognostic model's discrimination. The first threshold amounts to rating certainty in the model's ability to classify better than random chance. The other two approaches involve setting thresholds informed by other mechanisms for classification: clinician intuition or an alternative prognostic model developed for the same disease area and outcome. The choice of threshold will vary based on the context. Instead of relying on arbitrary discrimination cut-offs, our approach positions the observed discrimination within an informed spectrum, potentially aiding decisions about a prognostic model's practical utility.

Poison in the nursery: Mercury contamination in the tadpole-rearing sites of an Amazonian frog.

Artisanal and small-scale gold mining (ASGM) has become a major threat for Neotropical forests. This technique for obtaining gold is a substantial driver of small-scale deforestation and the largest contributor of Hg emissions to both the atmosphere and freshwater systems globally. Previous studies have demonstrated the impacts of Hg accumulation on various aquatic ecosystems and organisms. However, its consequences in other, more discrete systems such as phytotelmata (water-holding plant structures), and the organisms therein, have so far gone unnoticed. Here, we show high concentrations of Hg (mean ± SD: 1.43 ± 2.19 ppm) in phytotelmata and other small pools, the aquatic microenvironments used by the Neotropical poison frog Dendrobates tinctorius as tadpole-rearing sites. In 17 % of the cases, we detected Hg concentrations above the severe effect level (SEL = 2 ppm) for freshwater sediments. Hg concentrations varied depending on pool characteristics and tended to increase in proximity to known ASGM sites. We did not find an effect of Hg concentration on the number of D. tinctorius tadpoles in a given pool. Tadpoles were found in pools with concentrations of up to 8.68 ppm, suggesting that D. tinctorius fathers do not avoid pools with high Hg levels for tadpole deposition. While further research is needed to determine the potential effects of Hg on tadpole development, we found an intriguing tendency for tadpoles in later developmental stages to have lower body condition when occurring in pools with higher Hg concentrations. Our findings provide evidence of relevant Hg concentrations in the terrestrial water systems used by phytotelm-breeding anurans, and highlight the need of further field and experimental studies investigating the implications of Hg contamination for tadpole development and behaviour and the overall conservation of Amazonian biodiversity.

Electronic Patient-Reported Outcome Monitoring to Improve Quality of Life After Joint Replacement: Secondary Analysis of a Randomized Clinical Trial.

Importance: Although remote patient-reported outcome measure (PROM) monitoring has shown promising results in cancer care, there is a lack of research on PROM monitoring in orthopedics. Objective: To determine whether PROM monitoring can improve health outcomes for patients with joint replacement compared with the standard of care. Design, Setting, and Participants: A 2-group, patient-level randomized clinical trial (PROMoting Quality) across 9 German hospitals recruited patients aged 18 years or older with primary hip or knee replacement from October 1, 2019, to December 31, 2020, with follow-up until March 31, 2022. Interventions: Intervention and control groups received the standard of care and PROMs at hospital admission, discharge, and 12 months after surgery. In addition, the intervention group received PROMs at 1, 3, and 6 months after surgery. Based on prespecified PROM score thresholds, at these times, an automated alert signaled critical recovery paths to hospital study nurses. On notification, study nurses contacted patients and referred them to their physicians if necessary. Main Outcomes and Measures: The prespecified outcomes were the mean change in PROM scores (European Quality of Life 5-Dimension 5-Level version [EQ-5D-5L; range, -0.661 to 1.0, with higher values indicating higher levels of health-related quality of life (HRQOL)], European Quality of Life Visual Analogue Scale [EQ-VAS; range, 0-100, with higher values indicating higher levels of HRQOL], Hip Disability and Osteoarthritis Outcome Score-Physical Function Shortform [HOOS-PS; range, 0-100, with lower values indicating lower physical impairment] or Knee Injury and Osteoarthritis Outcome Score-Physical Function Shortform [KOOS-PS; range, 0-100, with lower values indicating lower physical impairment], Patient-Reported Outcomes Measurement Information System [PROMIS]-fatigue [range, 33.7-75.8, with lower values indicating lower levels of fatigue], and PROMIS-depression [range, 41-79.4, with lower values indicating lower levels of depression]) from baseline to 12 months after surgery. Analysis was on an intention-to-treat basis. Results: The study included 3697 patients with hip replacement (mean [SD] age, 65.8 [10.6] years; 2065 women [55.9%]) and 3110 patients with knee replacement (mean [SD] age, 66.0 [9.2] years; 1669 women [53.7%]). Exploratory analyses showed significantly better health outcomes in the intervention group on all PROMs except the EQ-5D-5L among patients with hip replacement, with a 2.10-point increase on the EQ-VAS in the intervention group compared with the control group (HOOS-PS, -1.86 points; PROMIS-fatigue, -0.69 points; PROMIS-depression, -0.57 points). Patients in the intervention group with knee replacement had a 1.24-point increase on the EQ-VAS, as well as significantly better scores on the KOOS-PS (-0.99 points) and PROMIS-fatigue (-0.84 points) compared with the control group. Mixed-effect models showed a significant difference in improvement on the EQ-VAS (hip replacement: effect estimate [EE], 1.66 [95% CI, 0.58-2.74]; knee replacement: EE, 1.71 [95% CI, 0.53-2.90]) and PROMIS-fatigue (hip replacement: EE, -0.65 [95% CI, -1.12 to -0.18]; knee replacement: EE, -0.71 [95% CI, -1.23 to -0.20]). The PROMIS-depression score was significantly reduced in the hip replacement group (EE, -0.60 [95% CI, -1.01 to -0.18]). Conclusions and Relevance: In this randomized clinical trial, the PROM-based monitoring intervention led to a small improvement in HRQOL and fatigue among patients with hip or knee replacement, as well as in depression among patients with hip replacement. Trial registration: Deutsches Register Klinischer Studien ID: DRKS00019916.

Active Control of Energy Transfer in Plasmonic Nanorod-Polyaniline Hybrids.

The hybridization of plasmonic energy and charge donors with polymeric acceptors is a possible means to overcome fast internal relaxation that limits potential photocatalytic applications for plasmonic nanomaterials. Polyaniline (PANI) readily hybridizes onto gold nanorods (AuNRs) and has been used for the sensitive monitoring of local refractive index changes. Here, we use single-particle spectroscopy to quantify a previously unreported plasmon damping mechanism in AuNR-PANI hybrids while actively tuning the PANI chemical structure. By eliminating contributions from heterogeneous line width broadening and refractive index changes, we identify efficient resonance energy transfer (RET) between AuNRs and PANI. We find that RET dominates the optical response in our AuNR-PANI hybrids during the dynamic tuning of the spectral overlap of the AuNR donor and PANI acceptor. Harnessing RET between plasmonic nanomaterials and an affordable and processable polymer such as PANI offers an alternate mechanism toward efficient photocatalysis with plasmonic nanoparticle antennas.

Heading toward Miniature Sensors: Electrical Conductance of Linearly Assembled Gold Nanorods.

Metal nanoparticles are increasingly used as key elements in the fabrication and processing of advanced electronic systems and devices. For future device integration, their charge transport properties are essential. This has been exploited, e.g., in the development of gold-nanoparticle-based conductive inks and chemiresistive sensors. Colloidal wires and metal nanoparticle lines can also be used as interconnection structures to build directional electrical circuits, e.g., for signal transduction. Our scalable bottom-up, template-assisted self-assembly creates gold-nanorod (AuNR) lines that feature comparably small widths, as well as good conductivity. However, the bottom-up approach poses the question about the consistency of charge transport properties between individual lines, as this approach leads to heterogeneities among those lines with regard to AuNR orientation, as well as line defects. Therefore, we test the conductance of the AuNR lines and identify requirements for a reliable performance. We reveal that multiple parallel AuNR lines (>11) are necessary to achieve predictable conductivity properties, defining the level of miniaturization possible in such a setup. With this system, even an active area of only 16 µm2 shows a higher conductance (~10-5 S) than a monolayer of gold nanospheres with dithiolated-conjugated ligands and additionally features the advantage of anisotropic conductance.

GRADE guidance 36: updates to GRADE's approach to addressing inconsistency.

OBJECTIVES: To update previous Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidance by addressing inconsistencies and interpreting subgroup analyses. STUDY DESIGN AND SETTING: Using an iterative process, we consulted with members of the GRADE working group through multiple rounds of written feedback and discussions at GRADE working group meetings. RESULTS: The guidance complements previous guidance with clarification in two areas: (1) assessing inconsistency and (2) assessing the credibility of possible effect modifiers that might explain inconsistency. Specifically, the guidance clarifies that inconsistency refers to variability in results, not in study characteristics; that inconsistency assessment for binary outcomes requires consideration of both relative and absolute effects; how to decide between narrower and broader questions in systematic reviews and guidelines; that, with the same evidence, ratings of inconsistency may differ depending on the target of certainty rating; and how GRADE inconsistency ratings relate to a statistical measure of inconsistency I2 depending on the context in which one views results. The second part of the guidance illustrates, based on a worked example, the use of the instrument to assess the credibility of effect modification analyses. The guidance explains the stepwise process of moving from a subgroup analysis to assessing the credibility of effect modification and, if found credible, to subgroup-specific effect estimates and GRADE certainty ratings. CONCLUSION: This updated guidance addresses specific conceptual and practical issues that systematic review authors frequently face when considering the degree of inconsistency in estimates of treatment effects across studies.

Tuning the pore structure of templated mesoporous poly(melamine-co-formaldehyde) particles toward diclofenac removal.

The increasing demand and implementation of pharmaceutics poses severe risk to different aquatic species as detectable contaminant in almost every surface water worldwide. Diclofenac (DCF) as one of the most common used analgesics was investigated as contaminant to be removed by adsorption onto nanoporous poly(melamine-co-formaldehyde) (PMF) particles featuring a very high amount of nitrogen functionalities. To achieve a high specific surface area (up to 416 m2/g) and a tunable pore system by hard templating, four different SiO2 nanoparticles were used as template. Differences in the pore formation and achieved pore structure were elucidated. For the first time, the adsorption of DCF onto PMF was tested. In batch adsorption experiments, impactful adsorption capacities as high as 76 µmol/g were achieved and complete removal at initial concentrations of 2 mg/L DCF. Differences in the connectivity and the micropore structure were decisive for uptake in low concentrations and the achieved adsorption capacity, respectively. As the presented PMF particles can be easily synthesized with the monomers formaldehyde and melamine combined with colloidal silica as sacrificial template and water as green solvent, this material presents a viable adsorbent for the removal of DCF at a larger scale. Our study further indicates a high potential for the removal of other pharmaceuticals.

PNIPAAm microgels with defined network architecture as temperature sensors in optical stretchers.

Stretching individual living cells with light is a standard method to assess their mechanical properties. Yet, heat introduced by the laser light of optical stretchers may unwittingly change the mechanical properties of cells therein. To estimate the temperature induced by an optical trap, we introduce cell-sized, elastic poly(N-isopropylacrylamide) (PNIPAAm) microgels that relate temperature changes to hydrogel swelling. For their usage as a standardized calibration tool, we analyze the effect of free-radical chain-growth gelation (FCG) and polymer-analogous photogelation (PAG) on hydrogel network heterogeneity, micromechanics, and temperature response by Brillouin microscopy and optical diffraction tomography. Using a combination of tailor-made PNIPAAm macromers, PAG, and microfluidic processing, we obtain microgels with homogeneous network architecture. With that, we expand the capability of standardized microgels in calibrating and validating cell mechanics analysis, not only considering cell and microgel elasticity but also providing stimuli-responsiveness to consider dynamic changes that cells may undergo during characterization.

GRADE Guidance 34: update on rating imprecision using a minimally contextualized approach.

OBJECTIVES: The aim of this study is to provide updated guidance on when The Grading of Recommendations Assessment, Development and Evaluation (GRADE) users should consider rating down more than one level for imprecision using a minimally contextualized approach. STUDY DESIGN AND SETTING: Based on the first GRADE guidance addressing imprecision rating in 2011, a project group within the GRADE Working Group conducted iterative discussions and presentations at GRADE Working Group meetings to produce this guidance. RESULTS: GRADE suggests aligning imprecision criterion for systematic reviews and guidelines using the approach that relies on thresholds and confidence intervals (CI) of absolute effects as a primary criterion for imprecision rating (i.e., CI approach). Based on the CI approach, when a CI appreciably crosses the threshold(s) of interest, one should consider rating down two or three levels. When the CI does not cross the threshold(s) and the relative effect is large, one should implement the optimal information size (OIS) approach. If the sample size of the meta-analysis is far less than the OIS, one should consider rating down more than one level for imprecision. CONCLUSION: GRADE provides updated guidance for imprecision rating in a minimally contextualized approach, with a focus on the circumstances in which one should seriously consider rating down two or three levels for imprecision.

GRADE guidance 35: update on rating imprecision for assessing contextualized certainty of evidence and making decisions.

OBJECTIVES: Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidance to rate the certainty domain of imprecision is presently not fully operationalized for rating down by two levels and when different baseline risk or uncertainty in these risks are considered. In addition, there are scenarios in which lowering the certainty of evidence by three levels for imprecision is more appropriate than lowering it by two levels. In this article, we conceptualize and operationalize rating down for imprecision by one, two and three levels for imprecision using the contextualized GRADE approaches and making decisions. METHODS: Through iterative discussions and refinement in online meetings and through email communication, we developed draft guidance to rating the certainty of evidence down by up to three levels based on examples. The lead authors revised the approach according to the feedback and the comments received during these meetings and developed GRADE guidance for how to apply it. We presented a summary of the results to all attendees of the GRADE Working Group meeting for feedback in October 2021 (approximately 80 people) where the approach was formally approved. RESULTS: This guidance provides GRADE's novel approach for the considerations about rating down for imprecision by one, two and three levels based on serious, very serious and extremely serious concerns. The approach includes identifying or defining thresholds for health outcomes that correspond to trivial or none, small, moderate or large effects and using them to rate imprecision. It facilitates the use of evidence to decision frameworks and also provides guidance for how to address imprecision about implausible large effects and trivial or no effects using the concept of the 'review information size' and for varying baseline risks. The approach is illustrated using practical examples, an online calculator and graphical displays and can be applied to dichotomous and continuous outcomes. CONCLUSION: In this GRADE guidance article, we provide updated guidance for how to rate imprecision using the partially and fully contextualized GRADE approaches for making recommendations or decisions, considering alternate baseline risks and for both dichotomous and continuous outcomes.

Retention and loss of PIT tags and surgically implanted devices in the Eurasian beaver.

BACKGROUND: Passive integrated transponder devices (PIT tags) are a valuable tool for individual identification of animals. Similarly, the surgical implantation of transmitters and bio-loggers can provide useful data on animal location, physiology and behavior. However, to avoid unnecessary recapture and related stress of study animals, PIT tags and bio-loggers should function reliably for long periods of time. Here, we evaluated the retention of PIT tags, and of very high frequency (VHF) transmitters and bio-loggers that were either implanted subcutaneously or into the peritoneal cavity of Eurasian beavers (Castor fiber). RESULTS: Over a 21-year period, we implanted PIT tags in 456 individuals and failed to detect a PIT tag at recapture in 30 cases, consisting of 26 individuals (6% of individuals). In all instances, we were still able to identify the individual due to the presence of unique ear tag numbers and tail scars. Moreover, we implanted 6 VHFs, 36 body temperature loggers and 21 heart rate loggers in 28 individuals, and experienced frequent loss of temperature loggers (at least 6 of 23 recaptured beavers) and heart rate loggers (10 of 18 recaptured beavers). No VHFs were lost in 2 recaptured beavers. CONCLUSIONS: Possible causes for PIT tag loss (or non-detection) were incorrect implantation, migration of the tag within the body, a foreign body reaction leading to ejection, or malfunctioning of the tag. We speculate that logger loss was related to a foreign body reaction, and that loggers were either rejected through the incision wound or, in the case of temperature loggers, possibly adhered and encapsulated to intestines, and then engulfed by the gastro-intestinal tract and ejected. We discuss animal welfare implications and give recommendations for future studies implanting bio-loggers into wildlife.

Troubling Aspects of the Trabecular Bone Score Adjustment for the Fracture Risk Assessment Tool (FRAX®).

The Fracture Risk Assessment Tool (FRAX®) is widely used to estimate the 10-year risk of hip fracture and major osteoporotic fracture (MOF, defined as a hip, humerus, wrist, or clinical vertebral fracture). In 2015, McCloskey and colleagues published an adjustment to FRAX® based on the trabecular bone score (TBS). In 2017, the adjustment was updated to use a different calculation for MOF when TBS was measured by Hologic in people assigned male sex at birth. However, this update occurred only on the website hosting FRAX® adjusted for TBS without any corresponding publication of the details of this update or its derivation or validation. In addition to this unpublished update, FRAX® adjusted for TBS also gives impossible results in certain situations, manifesting most clearly in people above a certain age who are at high 10-year risk. Further still, there are inexplicable divergences in the 10-year estimates of hip fracture between the equations published in 2015 and the estimates one obtains if using the website version, which manifest most clearly in people over 80 years old, even at lower 10-year risks. We call on the authors of the TBS adjustment to help the users of FRAX® and FRAX® adjusted for TBS by addressing these matters.

Identification of a Two-Coordinate Iron(I)-Oxalate Complex.

Exotic oxidation states of the first-row transition metals have recently attracted much interest. In order to investigate the oxidation states of a series of iron-oxalate complexes, an aqueous solution of iron(III) nitrate and oxalic acid was studied by infrared free liquid matrix-assisted laser desorption/ionization as well as ionspray mass spectrometry. Here, we show that iron is not only detected in its common oxidation states +II and +III, but also in its unusual oxidation state +I, detectable in both positive-ion and in negative-ion modes, respectively. Vibrational spectra of the gas phase anionic iron oxalate complexes [FeIII (C2 O4 )2 ]- , [FeII (C2 O4 )CO2 ]- , and [FeI (C2 O4 )]- were measured by means of infrared photodissociation spectroscopy and their structures were assigned by comparison to anharmonic vibrational spectra based on second-order perturbation theory.

The impact of bio-logging on body weight change of the Eurasian beaver.

Bio-logging is a common method to collect ecological data on wild animals, but might also induce stress, reduce body condition, and alter behavior. Eurasian beavers (Castor fiber) are a semi-aquatic and nocturnal species that are challenging to observe in the wild. Bio-loggers are hence useful tools to study their behaviour and movements, but this raises concerns of potential negative impacts of tagging. To investigate the potential negative impacts of glue-on tags, we compared body weight change for tagged and untagged Eurasian beavers. We hypothesized that tagged beavers would gain less body weight compared to untagged beavers, and that weight change might be affected by tagging length, tag weight, water temperature and the season of tagging. Daily percentage body weight change in relation to initial body weight during the first capture was compared during 57 tagging periods (18±7 days) and 32 controls periods (64±47 days). Body weight change varied between the two groups, with untagged beavers on average gaining daily weight whilst tagged beavers on average lost weight daily, indicating a negative effect of tagging. The average reduction in percentage body weight change per day for tagged beavers was small (0.1 ± 0.3%), and with large individual variation. Neither tag weight, number of tagging days, nor season were important in explaining body weight change of tagged animals. In other words, we found that tagging reduced daily body weight during the tagging period but were unable to determine the mechanism(s) responsible for this decline. Detrimental effects of tagging have important implications for animal welfare and can introduce bias in data that are collected. This calls for careful consideration in the use of tags. We conclude that studies investigating the effects of tagging should consider individual variation in the effects of tagging and, where possible, compare tagged animals with a control group.

Fine-scale movement patterns and habitat selection of little owls (Athene noctua) from two declining populations.

Advances in bio-logging technology for wildlife monitoring have expanded our ability to study space use and behavior of many animal species at increasingly detailed scales. However, such data can be challenging to analyze due to autocorrelation of GPS positions. As a case study, we investigated spatiotemporal movements and habitat selection in the little owl (Athene noctua), a bird species that is declining in central Europe and verges on extinction in Denmark. We equipped 6 Danish food-supplemented little owls and 6 non-supplemented owls in the Czech Republic with high-resolution GPS loggers that recorded one position per minute. Nightly space use, measured as 95% kernel density estimates, of Danish male owls were on average 62 ha (± 64 SD, larger than any found in previous studies) compared to 2 ha (± 1) in females, and to 3 ± 1 ha (males) versus 3 ± 5 ha (females) in the Czech Republic. Foraging Danish male owls moved on average 4-fold further from their nest and at almost double the distance per hour than Czech males. To create availability data for the habitat selection analysis, we accounted for high spatiotemporal autocorrelation of the GPS data by simulating correlated random walks with the same autocorrelation structure as the actual little owl movement trajectories. We found that habitat selection was similar between Danish and Czech owls, with individuals selecting for short vegetation and areas with high structural diversity. Our limited sample size did not allow us to infer patterns on a population level, but nevertheless demonstrates how high-resolution GPS data can help to identify critical habitat requirements to better formulate conservation actions on a local scale.

Understanding spatio-temporal patterns of deer-vehicle collisions to improve roadkill mitigation.

Vehicles collide with hundreds of thousands of deer on European roads each year. This leads to animal deaths and suffering, economic damage and risks for human safety, making the reduction of road mortality a major field in conservation biology. In order to successfully reduce roadkill, we need improved knowledge regarding spatio-temporal patterns of deer-vehicle collisions (DVCs) on a landscape scale. Here, we analyzed >85,000 DVCs collected over 17 years in Denmark to investigate changes in the number of DVCs over time and to find spatio-temporal patterns of DVC occurrence. We used a use-availability design - originally developed for habitat selection analyses - to compare DVCs involving roe deer (Capreolus capreolus), red deer (Cervus elaphus) and fallow deer (Dama dama) with random road locations on a landscape scale. This approach enabled us to combine temporal (seasonal and diel variation), spatial (land cover, road density and type) and other relevant variables (deer population density, traffic, and deer activity) within the same analysis. We found that factors related to infrastructure and land cover were most important in explaining patterns of DVCs, but seasonal and diel changes, deer activity, and population density were also important in predicting the occurrence of DVCs. Importantly, patterns of DVCs were largely similar between the three deer species, with more DVCs occurring at intermediate traffic density, increasing forest cover, during dusk and dawn, and with increasing deer activity and population density. The strong and consistent patterns found here will allow the development of flexible mitigation measures. We propose that our findings could be used to develop a spatio-temporally flexible warning system for smartphones and navigation systems that is based on existing map providers, making it a widely available and cheap mitigation measure.