Recoverability and estimation of causal effects under typical multivariable missingness mechanisms.

In the context of missing data, the identifiability or "recoverability" of the average causal effect (ACE) depends not only on the usual causal assumptions but also on missingness assumptions that can be depicted by adding variable-specific missingness indicators to causal diagrams, creating missingness directed acyclic graphs (m-DAGs). Previous research described canonical m-DAGs, representing typical multivariable missingness mechanisms in epidemiological studies, and examined mathematically the recoverability of the ACE in each case. However, this work assumed no effect modification and did not investigate methods for estimation across such scenarios. Here, we extend this research by determining the recoverability of the ACE in settings with effect modification and conducting a simulation study to evaluate the performance of widely used missing data methods when estimating the ACE using correctly specified g-computation. Methods assessed were complete case analysis (CCA) and various implementations of multiple imputation (MI) with varying degrees of compatibility with the outcome model used in g-computation. Simulations were based on an example from the Victorian Adolescent Health Cohort Study (VAHCS), where interest was in estimating the ACE of adolescent cannabis use on mental health in young adulthood. We found that the ACE is recoverable when no incomplete variable (exposure, outcome, or confounder) causes its own missingness, and nonrecoverable otherwise, in simplified versions of 10 canonical m-DAGs that excluded unmeasured common causes of missingness indicators. Despite this nonrecoverability, simulations showed that MI approaches that are compatible with the outcome model in g-computation may enable approximately unbiased estimation across all canonical m-DAGs considered, except when the outcome causes its own missingness or causes the missingness of a variable that causes its own missingness. In the latter settings, researchers may need to consider sensitivity analysis methods incorporating external information (e.g., delta-adjustment methods). The VAHCS case study illustrates the practical implications of these findings.

In Retrospect: Root-Cause Analysis of Structure-Activity Relationships in IRAK4 Inhibitor Zimlovisertib (PF-06650833).

In this paper, we disclose insights on the root causes of three structure-activity relationship (SAR) observations encountered in the discovery of the IRAK4 inhibitor Zimlovisertib (PF-06650833). The first is a nonlinear potency SAR encountered with the isoquinoline ether substituent, the second is a potency enhancement introduced by fluorine substitution on the lactam, and the third is a slight potency preference for all-syn (2S,3S,4S) stereochemistry in the fluorine-substituted lactam. We present new data that help to inform us of the origins of these unexpected SAR trends.

Adaptive platform trials rather than randomised controlled trials for paediatric sepsis.

Adaptive platform trials (APTs) offer a promising alternative to traditional randomised controlled trials for evaluating treatments for paediatric sepsis. Randomised controlled trials, despite being the gold standard for establishing causality between interventions and outcomes, make many assumptions about disease prevalence, severity and intervention effects, which are often incorrect. As a result, the evidence for most treatments for paediatric sepsis are based on low-quality evidence. APTs use accrued data rather than assumptions to power trial adaptations. They can assess multiple treatments simultaneously with shared research infrastructure. As such, APTs offer a more efficient, flexible and more effective way to identify optimal treatments. The proposed Paediatric Adaptive Sepsis Platform Trial, leveraging the Paediatric Research in Emergency Departments International Collaborative network's infrastructure, will evaluate resuscitation fluids, vasoactive medications, corticosteroids and antimicrobials. This trial has the potential to substantially impact clinical practice and reduce global sepsis mortality in children.

Statistical analyses of ordinal outcomes in randomised controlled trials: a scoping review.

BACKGROUND: Randomised controlled trials (RCTs) aim to estimate the causal effect of one or more interventions relative to a control. One type of outcome that can be of interest in an RCT is an ordinal outcome, which is useful to answer clinical questions regarding complex and evolving patient states. The target parameter of interest for an ordinal outcome depends on the research question and the assumptions the analyst is willing to make. This review aimed to provide an overview of how ordinal outcomes have been used and analysed in RCTs. METHODS: The review included RCTs with an ordinal primary or secondary outcome published between 2017 and 2022 in four highly ranked medical journals (the British Medical Journal, New England Journal of Medicine, The Lancet, and the Journal of the American Medical Association) identified through PubMed. Details regarding the study setting, design, the target parameter, and statistical methods used to analyse the ordinal outcome were extracted. RESULTS: The search identified 309 studies, of which 144 were eligible for inclusion. The most used target parameter was an odds ratio, reported in 78 (54%) studies. The ordinal outcome was dichotomised for analysis in 47 ( 33 % ) studies, and the most common statistical model used to analyse the ordinal outcome on the full ordinal scale was the proportional odds model (64 [ 44 % ] studies). Notably, 86 (60%) studies did not explicitly check or describe the robustness of the assumptions for the statistical method(s) used. CONCLUSIONS: The results of this review indicate that in RCTs that use an ordinal outcome, there is variation in the target parameter and the analytical approaches used, with many dichotomising the ordinal outcome. Few studies provided assurance regarding the appropriateness of the assumptions and methods used to analyse the ordinal outcome. More guidance is needed to improve the transparent reporting of the analysis of ordinal outcomes in future trials.

Advancing randomized controlled trial methodologies: The place of innovative trial design in eating disorders research.

Randomized controlled trials can be used to generate evidence on the efficacy and safety of new treatments in eating disorders research. Many of the trials previously conducted in this area have been deemed to be of low quality, in part due to a number of practical constraints. This article provides an overview of established and more innovative clinical trial designs, accompanied by pertinent examples, to highlight how design choices can enhance flexibility and improve efficiency of both resource allocation and participant involvement. Trial designs include individually randomized, cluster randomized, and designs with randomizations at multiple time points and/or addressing several research questions (master protocol studies). Design features include the use of adaptations and considerations for pragmatic or registry-based trials. The appropriate choice of trial design, together with rigorous trial conduct, reporting and analysis, can establish high-quality evidence to advance knowledge in the field. It is anticipated that this article will provide a broad and contemporary introduction to trial designs and will help researchers make informed trial design choices for improved testing of new interventions in eating disorders. PUBLIC SIGNIFICANCE: There is a paucity of high quality randomized controlled trials that have been conducted in eating disorders, highlighting the need to identify where efficiency gains in trial design may be possible to advance the eating disorder research field. We provide an overview of some key trial designs and features which may offer solutions to practical constraints and increase trial efficiency.

Overcoming aggregation with laser heated nanoelectrospray mass spectrometry: thermal stability and pathways for loss of bicarbonate from carbonic anhydrase II.

Variable temperature electrospray mass spectrometry is useful for multiplexed measurements of the thermal stabilities of biomolecules, but the ionization process can be disrupted by aggregation-prone proteins/complexes that have irreversible unfolding transitions. Resistively heating solutions containing a mixture of bovine carbonic anhydrase II (BCAII), a CO2 fixing enzyme involved in many biochemical pathways, and cytochrome c leads to complete loss of carbonic anhydrase signal and a significant reduction in cytochrome c signal above ∼72 °C due to aggregation. In contrast, when the tips of borosilicate glass nanoelectrospray emitters are heated with a laser, complete thermal denaturation curves for both proteins are obtained in <1 minute. The simultaneous measurements of the melting temperature of BCAII and BCAII bound to bicarbonate reveal that the bicarbonate stabilizes the folded form of this protein by ∼6.4 °C. Moreover, the temperature dependences of different bicarbonate loss pathways are obtained. Although protein analytes are directly heated by the laser for only 140 ms, heat conduction further up the emitter leads to a total analyte heating time of ∼41 s. Pulsed laser heating experiments could reduce this time to ∼0.5 s for protein aggregation that occurs on a faster time scale. Laser heating provides a powerful method for studying the detailed mechanisms of cofactor/ligand loss with increasing temperature and promises a new tool for studying the effect of ligands, drugs, growth conditions, buffer additives, or other treatments on the stabilities of aggregation-prone biomolecules.

Facial Function in Bell Palsy in a Cohort of Children Randomized to Prednisolone or Placebo 12 Months After Diagnosis.

BACKGROUND: Information on the medium-term recovery of children with Bell palsy or acute idiopathic lower motor neuron facial paralysis is limited. METHODS: We followed up children aged 6 months to <18 years with Bell palsy for 12 months after completion of a randomized trial on the use of prednisolone. We assessed facial function using the clinician-administered House-Brackmann scale and the modified parent-administered House-Brackmann scale. RESULTS: One hundred eighty-seven children were randomized to prednisolone (n = 93) or placebo (n = 94). At six months, the proportion of patients who had recovered facial function based on the clinician-administered House-Brackmann scale was 98% (n = 78 of 80) in the prednisolone group and 93% (n = 76 of 82) in the placebo group. The proportion of patients who had recovered facial function based on the modified parent-administered House-Brackmann scale was 94% (n = 75 of 80) vs 89% (n = 72 of 81) at six months (OR 1.88; 95% CI 0.60, 5.86) and 96% (n = 75 of 78) vs 92% (n = 73 of 79) at 12 months (OR 3.12; 95% CI 0.61, 15.98). CONCLUSIONS: Although the vast majority had complete recovery of facial function at six months, there were some children without full recovery of facial function at 12 months, regardless of prednisolone use.

"It Gives Me Peace of Mind So I Can Focus on Healing": Views on Advance Care Planning for Older Surgical Patients.

Introduction: The period of time before an elective operation may be an opportune time to engage older adults in advance care planning (ACP). Past interventions have not been readily incorporated into surgical workflows leaving a need for ACP tools that are generalizable, easy to implement, and effective. Design: This is a qualitative study. Setting and Subjects: Older adults with a history of cancer and a recent major operation were recruited through their surgical oncologist at a tertiary medical center in the United States. Interviews were conducted to determine how to adapt the validated PrepareForYourCare.org ACP program with electronic health record prompts for the perioperative setting and openness to introducing ACP during a presurgical visit. We used qualitative content analysis to determine themes. Results: Eight themes were identified: (1) ACP as static and private, (2) people expected a prompt, (3) family trusted to do the "right" thing, (4) lack of relationship or comfort with providers, (5) a team-based approach can be helpful, (6) surgeon's expertise (e.g., prognosis and surgical risk), (7) ACP belongs on the surgical checklist, and (8) patients would welcome a conversation starter. Discussion: Older surgical patients are interested in engaging with ACP, particularly if prompted, and believe it has a place on the preoperative "checklist." Conclusions: To effectively engage patients with ACP, a combination of routine prompts by the health care team and patient-centered follow-up may be required.

BECC438b TLR4 agonist supports unique immune response profiles from nasal and muscular DTaP pertussis vaccines in murine challenge models.

The protection afforded by acellular pertussis vaccines wanes over time, and there is a need to develop improved vaccine formulations. Options to improve the vaccines involve the utilization of different adjuvants and administration via different routes. While intramuscular (IM) vaccination provides a robust systemic immune response, intranasal (IN) vaccination theoretically induces a localized immune response within the nasal cavity. In the case of a Bordetella pertussis infection, IN vaccination results in an immune response that is similar to natural infection, which provides the longest duration of protection. Current acellular formulations utilize an alum adjuvant, and antibody levels wane over time. To overcome the current limitations with the acellular vaccine, we incorporated a novel TLR4 agonist, BECC438b, into both IM and IN acellular formulations to determine its ability to protect against infection in a murine airway challenge model. Following immunization and challenge, we observed that DTaP + BECC438b reduced bacterial burden within the lung and trachea for both administration routes when compared with mock-vaccinated and challenged (MVC) mice. Interestingly, IN administration of DTaP + BECC438b induced a Th1-polarized immune response, while IM vaccination polarized toward a Th2 immune response. RNA sequencing analysis of the lung demonstrated that DTaP + BECC438b activates biological pathways similar to natural infection. Additionally, IN administration of DTaP + BECC438b activated the expression of genes involved in a multitude of pathways associated with the immune system. Overall, these data suggest that BECC438b adjuvant and the IN vaccination route can impact efficacy and responses of pertussis vaccines in pre-clinical mouse models.

An extended wave of global mRNA deadenylation sets up a switch in translation regulation across the mammalian oocyte-to-embryo transition.

Without new transcription, gene expression across the oocyte-to-embryo transition (OET) relies instead on regulation of mRNA poly(A) tails to control translation. However, how tail dynamics shape translation across the OET in mammals remains unclear. We perform long-read RNA sequencing to uncover poly(A) tail lengths across the mouse OET and, incorporating published ribosome profiling data, provide an integrated, transcriptome-wide analysis of poly(A) tails and translation across the entire transition. We uncover an extended wave of global deadenylation during fertilization in which short-tailed, oocyte-deposited mRNAs are translationally activated without polyadenylation through resistance to deadenylation. Subsequently, in the embryo, mRNAs are readenylated and translated in a surge of global polyadenylation. We further identify regulation of poly(A) tail length at the isoform level and stage-specific enrichment of mRNA sequence motifs among regulated transcripts. These data provide insight into the stage-specific mechanisms of poly(A) tail regulation that orchestrate gene expression from oocyte to embryo in mammals.

Handling missing data when estimating causal effects with Targeted Maximum Likelihood Estimation.

Targeted Maximum Likelihood Estimation (TMLE) is increasingly used for doubly robust causal inference, but how missing data should be handled when using TMLE with data-adaptive approaches is unclear. Based on the Victorian Adolescent Health Cohort Study, we conducted a simulation study to evaluate eight missing data methods in this context: complete-case analysis, extended TMLE incorporating outcome-missingness model, missing covariate missing indicator method, five multiple imputation (MI) approaches using parametric or machine-learning models. Six scenarios were considered, varying in exposure/outcome generation models (presence of confounder-confounder interactions) and missingness mechanisms (whether outcome influenced missingness in other variables and presence of interaction/non-linear terms in missingness models). Complete-case analysis and extended TMLE had small biases when outcome did not influence missingness in other variables. Parametric MI without interactions had large bias when exposure/outcome generation models included interactions. Parametric MI including interactions performed best in bias and variance reduction across all settings, except when missingness models included a non-linear term. When choosing a method to handle missing data in the context of TMLE, researchers must consider the missingness mechanism and, for MI, compatibility with the analysis method. In many settings, a parametric MI approach that incorporates interactions and non-linearities is expected to perform well.

Sleep, Diet Quality, and Lipid Profile Assessment in NCAA Division I Acrobatics and Tumbling Student-Athletes: A Cross-Sectional Study.

OBJECTIVE: Acrobatics and Tumbling (A&T), an emerging National Collegiate Athletics Association (NCAA) sport, involves athletes with rigorous training backgrounds, usually extending from youth through early adulthood. This study examines the sleep health, diet quality, and lipid profile of A&T athletes clustered by their performance position. METHODS: Forty-two A&T athletes, clustered as tops (n = 19; age = 19.6 ± 1.0 years; body mass index [BMI] = 22.3 ± 1.7 kg/m2) and bases (n = 23; age = 19.6 ± 1.3 years; BMI = 25.7 ± 2.5 kg/m2), completed preseason sleep and diet quality (Rapid Eating Assessment for Participants-Shortened [REAP-S]) surveys. Fasting blood samples were collected for lipid analysis. Body composition was assessed via dual-energy X-ray absorptiometry. RESULTS: Most athletes (71.4%; base n = 14, top n = 16) reported insufficient sleep (≤7 hours) and "good" sleep quality (90.4%, n = 38; base n = 18, top n = 20). Average REAP-S score was 29.24 ± 3.74. Approximately 31% (n = 13) displayed at least one undesirable lipid concentration according to medical guidelines for normal levels (total cholesterol [TC] < 200 mg/dL, triglycerides [TG] < 150 mg/dL, high-density lipoprotein cholesterol [HDL-C] > 40 mg/dL, low-density lipoprotein cholesterol [LDL-C] < 130 mg/dL). Approximately 20% exhibited elevated TC (top n = 4, base n = 4), 12.5% had elevated TG (base n = 5), 2.5% showed low HDL-C (base n = 1), and 10% presented elevated LDL-C (top n = 2, base n = 2). CONCLUSIONS: Most athletes experienced suboptimal sleep (≤7 hours/night) and 31% displayed at least one undesirable lipid concentration (elevated TC, TG, or LDL-C or reduced HDL-C). Tailoring interventions with sports dietitians is recommended, focused on increasing monounsaturated and polyunsaturated fat intake while reducing saturated fat consumption. These interventions could mitigate cardiovascular risks, improve recovery, and possibly enhance athletic performance.

A comparison of strategies for selecting auxiliary variables for multiple imputation.

Multiple imputation (MI) is a popular method for handling missing data. Auxiliary variables can be added to the imputation model(s) to improve MI estimates. However, the choice of which auxiliary variables to include is not always straightforward. Several data-driven auxiliary variable selection strategies have been proposed, but there has been limited evaluation of their performance. Using a simulation study we evaluated the performance of eight auxiliary variable selection strategies: (1, 2) two versions of selection based on correlations in the observed data; (3) selection using hypothesis tests of the "missing completely at random" assumption; (4) replacing auxiliary variables with their principal components; (5, 6) forward and forward stepwise selection; (7) forward selection based on the estimated fraction of missing information; and (8) selection via the least absolute shrinkage and selection operator (LASSO). A complete case analysis and an MI analysis using all auxiliary variables (the "full model") were included for comparison. We also applied all strategies to a motivating case study. The full model outperformed all auxiliary variable selection strategies in the simulation study, with the LASSO strategy the best performing auxiliary variable selection strategy overall. All MI analysis strategies that we were able to apply to the case study led to similar estimates, although computational time was substantially reduced when variable selection was employed. This study provides further support for adopting an inclusive auxiliary variable strategy where possible. Auxiliary variable selection using the LASSO may be a promising alternative when the full model fails or is too burdensome.

Molecular profiling of human blastocysts reveals primitive endoderm defects among embryos of decreased implantation potential.

Human embryo implantation is remarkably inefficient, and implantation failure remains among the greatest obstacles in treating infertility. Gene expression data from human embryos have accumulated rapidly in recent years; however, identification of the subset of genes that determine successful implantation remains a challenge. We leverage clinical morphologic grading-known for decades to correlate with implantation potential-and transcriptome analyses of matched embryonic and abembryonic samples to identify factors and pathways enriched and depleted in human blastocysts of good and poor morphology. Unexpectedly, we discovered that the greatest difference was in the state of extraembryonic primitive endoderm (PrE) development, with relative deficiencies in poor morphology blastocysts. Our results suggest that implantation success is most strongly influenced by the embryonic compartment and that deficient PrE development is common among embryos with decreased implantation potential. Our study provides a valuable resource for those investigating the markers and mechanisms of human embryo implantation.

Electronic Structure and Photophysics of Low Spin d5 Metallocenes.

The electronic structure and photophysics of two low spin metallocenes, decamethylmanganocene (MnCp*2) and decamethylrhenocene (ReCp*2), were investigated to probe their promise as photoredox reagents. Computational studies support the assignment of 2E2 ground state configurations and low energy ligand-to-metal charge transfer transitions for both complexes. Weak emission is observed at room temperature for ReCp*2 with τ = 1.8 ns in pentane, whereas MnCp*2 is not emissive. Calculation of the excited state reduction potentials for both metallocenes reveal their potential potency as excited state reductants (E°'([MnCp*2]+/0*) = -3.38 V and E°'([ReCp*2]+/0*) = -2.61 V vs Fc+/0). Comparatively, both complexes exhibit mild potentials for photo-oxidative processes (E°'([MnCp*2]0*/-) = -0.18 V and E°'([ReCp*2]0*/-) = -0.20 V vs Fc+/0). These results showcase the rich electronic structure of low spin d5 metallocenes and their promise as excited state reductants.

Dietary Intake and Menstrual Health among Acrobatics and Tumbling NCAA Division I Student-Athletes.

OBJECTIVE: Acrobatics & Tumbling (A&T) is an emerging sport in the National Collegiate Athletic Association that lacks research regarding the dietary intake and health of A&T student-athletes (A&Tsa). This study assessed the dietary intake adequacy, estimated energy availability (EA), self-reported menstrual health, and body composition of A&Tsa. METHODS: Twenty-four female A&Tsa participated during week 8 of the preseason (11 top: Age= 20.1 ± 0.9 years; BMI= 22.1 ± 1.7 kg/m2; 13 base: Age= 19.5 ± 1.3 years; BMI= 26.2 ± 2.7 kg/m2). Total energy intake (TEI) and macronutrient intakes were assessed via a paper-based 3-day dietary recall. Resting Metabolic Rate [RMR = 500 + 22 * fat-free mass (FFM)] and energy availability [EA = (TEI - exercise energy expenditure)/FFM)] were estimated; and LEAF-Q assessed menstrual health. Body composition was measured using Dual-Energy X-Ray Absorptiometry. Macronutrient intakes and EA were compared to sports nutrition recommendations (carbohydrate: 6-10 g/kg; protein: 1.2-2.0 g/kg) and the Acceptable Macronutrient Distribution Range (carbohydrate: 45-65%; protein: 10-35%; fat: 20-35%). RESULTS: TEI was 1753 ± 467 kcal (top) and 1980 ± 473.8 kcal (base). A total of 20.8% of A&Tsa failed to meet RMR with TEI, with a higher prevalence in the top (-266 ± 219.2 kcal, n = 3) vs. base (-414.3 ± 534.4 kcal, n = 2) A&Tsa. Top and base A&Tsa had both low EA (28.8 ± 13.4 kcals·FFM-1; 23.8 ± 9.5 kcals·FFM-1) and inadequate carbohydrate intake averages (4.2 ± 1.3 g/kg; 3.5 ± 1.1 g/kg, p < 0.001), respectively. A total of 17% of A&Tsa reported secondary amenorrhea, with a higher prevalence in the top (27.3%, n = 3) vs. the base (7.7%, n = 1). CONCLUSION: TEI and carbohydrate intake of the majority of A&Tsa were below recommendations. Sports dietitians should encourage and educate A&Tsa about following an adequate diet that meets energy and sports-specific macronutrient needs.

Pain in children with Bell's palsy: secondary analysis of a randomised controlled trial.

OBJECTIVE: To describe the prevalence and severity of pain experienced by children with Bell's palsy over the first 6 months of illness and its association with the severity of facial paralysis. METHODS: This was a secondary analysis of data obtained in a phase III, triple-blinded, randomised, placebo-controlled trial of prednisolone for the treatment of Bell's palsy in children aged 6 months to <18 years conducted between 13 October 2015 and 23 August 2020 in Australia and New Zealand. Children were recruited within 72 hours of symptom onset and pain was assessed using a child-rated visual analogue scale (VAS), a child-rated Faces Pain Score-Revised (FPS-R) and/or a parent-rated VAS at baseline, and at 1, 3 and 6 months until recovered, and are reported combined across treatment groups. RESULTS: Data were available for 169 of the 187 children randomised from at least one study time point. Overall, 37% (62/169) of children reported any pain at least at one time point. The frequency of any pain reported using the child-rated VAS, child-rated FPS-R and parent-rated VAS was higher at the baseline assessment (30%, 23% and 27%, respectively) compared with 1-month (4%, 0% and 4%, respectively) and subsequent follow-up assessments. At all time points, the median pain score on all three scales was 0 (no pain). CONCLUSIONS: Pain in children with Bell's palsy was infrequent and primarily occurred early in the disease course and in more severe disease. The intensity of pain, if it occurs, is very low throughout the clinical course of disease. TRIAL REGISTRATION NUMBER: ACTRN12615000563561.