436 research outputs found

    Implementation of prognostic machine learning algorithms in paediatric chronic respiratory conditions: a scoping review.

    Get PDF
    Machine learning (ML) holds great potential for predicting clinical outcomes in heterogeneous chronic respiratory diseases (CRD) affecting children, where timely individualised treatments offer opportunities for health optimisation. This paper identifies rate-limiting steps in ML prediction model development that impair clinical translation and discusses regulatory, clinical and ethical considerations for ML implementation. A scoping review of ML prediction models in paediatric CRDs was undertaken using the PRISMA extension scoping review guidelines. From 1209 results, 25 articles published between 2013 and 2021 were evaluated for features of a good clinical prediction model using the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines.Most of the studies were in asthma (80%), with few in cystic fibrosis (12%), bronchiolitis (4%) and childhood wheeze (4%). There were inconsistencies in model reporting and studies were limited by a lack of validation, and absence of equations or code for replication. Clinician involvement during ML model development is essential and diversity, equity and inclusion should be assessed at each step of the ML pipeline to ensure algorithms do not promote or amplify health disparities among marginalised groups. As ML prediction studies become more frequent, it is important that models are rigorously developed using published guidelines and take account of regulatory frameworks which depend on model complexity, patient safety, accountability and liability

    The impact of asking intention or self-prediction questions on subsequent behavior: a meta-analysis

    Get PDF
    The current meta-analysis estimated the magnitude of the impact of asking intention and self-prediction questions on rates of subsequent behavior, and examined mediators and moderators of this question–behavior effect (QBE). Random-effects meta-analysis on 116 published tests of the effect indicated that intention/prediction questions have a small positive effect on behavior (d+ = 0.24). Little support was observed for attitude accessibility, cognitive dissonance, behavioral simulation, or processing fluency explanations of the QBE. Multivariate analyses indicated significant effects of social desirability of behavior/behavior domain (larger effects for more desirable and less risky behaviors), difficulty of behavior (larger effects for easy-to-perform behaviors), and sample type (larger effects among student samples). Although this review controls for co-occurrence of moderators in multivariate analyses, future primary research should systematically vary moderators in fully factorial designs. Further primary research is also needed to unravel the mechanisms underlying different variants of the QBE

    Where do we go from here? - Opportunities and barriers to the career development of trial managers: a survey of UK-based trial management professionals

    Get PDF
    BackgroundClinical trials commonly have a dedicated trial manager and effective trial management is essential to the successful delivery of high-quality trials. Trial managers have diverse experience and currently there is no standardised structured career pathway. The UK Trial Managers’ Network (UKTMN) surveyed its members to understand what is important to them with respect to career development since this would be important in the development of any initiative intended to develop a skilled workforce.MethodsWe conducted an online survey of UKTMN members, who are trial management professionals, working on academic-led trials in the UK. Members were asked what they perceive as opportunities and barriers to career development. Two reminders were sent to facilitate completion of the survey, and responders were offered the opportunity to enter a prize draw for waived fees at the UKTMN annual meeting. Data were analysed descriptively by using Stata (version 15.1), and free-text responses were reviewed for themes.ResultsThe survey was sent to 819 UKTMN members; 433 responses were received, although 13 were from non-UKTMN members; thus 420 respondents' data were included in analyses. Respondents were representative of UKTMN membership; however, more responses were received by trial managers based in registered clinical trials units (CTUs). The top three opportunities for career development were (i) training, (ii) helping design trials and (iii) undertaking relevant qualifications. The top three barriers were (i) funding, (ii) few opportunities to get involved in development activities aside from managing a trial and (iii) unclear organisational career pathway. Almost all respondents (401/420, 95.4%) considered career development either very or quite important. Although all respondents had a day-to-day role in managing trials, there was huge disparity between job titles.ConclusionCareer development is important to trial managers yet there is a lack of a structured pathway. The enablers and disablers to career development for trial managers should be clearly considered by the clinical trial community and, in particular, employers, sponsors and funders in order to develop a highly skilled workforce of trial managers, who are key to the delivery of trials

    Mendelian randomisation for mediation analysis: current methods and challenges for implementation

    Get PDF
    Mediation analysis seeks to explain the pathway(s) through which an exposure affects an outcome. Traditional, non-instrumental variable methods for mediation analysis experience a number of methodological difficulties, including bias due to confounding between an exposure, mediator and outcome and measurement error. Mendelian randomisation (MR) can be used to improve causal inference for mediation analysis. We describe two approaches that can be used for estimating mediation analysis with MR: multivariable MR (MVMR) and two-step MR. We outline the approaches and provide code to demonstrate how they can be used in mediation analysis. We review issues that can affect analyses, including confounding, measurement error, weak instrument bias, interactions between exposures and mediators and analysis of multiple mediators. Description of the methods is supplemented by simulated and real data examples. Although MR relies on large sample sizes and strong assumptions, such as having strong instruments and no horizontally pleiotropic pathways, our simulations demonstrate that these methods are unaffected by confounders of the exposure or mediator and the outcome and non-differential measurement error of the exposure or mediator. Both MVMR and two-step MR can be implemented in both individual-level MR and summary data MR. MR mediation methods require different assumptions to be made, compared with non-instrumental variable mediation methods. Where these assumptions are more plausible, MR can be used to improve causal inference in mediation analysis. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10654-021-00757-1

    The Molecular Chaperone HSP90 Promotes Notch Signaling in the Germline of Caenorhabditis elegans

    Get PDF
    In a genetic screen to identify genes that promote GLP-1/Notch signaling in Caenorhabditis elegans germline stem cells, we found a single mutation, om40, defining a gene called ego-3. ego-3(om40) causes several defects in the soma and the germline, including paralysis during larval development, sterility, delayed proliferation of germline stem cells, and ectopic germline stem cell proliferation. Whole genome sequencing identified om40 as an allele of hsp-90, previously known as daf-21, which encodes the C. elegans ortholog of the cytosolic form of HSP90. This protein is a molecular chaperone with a central position in the protein homeostasis network, which is responsible for proper folding, structural maintenance, and degradation of proteins. In addition to its essential role in cellular function, HSP90 plays an important role in stem cell maintenance and renewal. Complementation analysis using a deletion allele of hsp-90 confirmed that ego-3 is the same gene. hsp-90(om40) is an IN conservative missense mutation of a highly conserved residue in the middle domain of HSP-90. RNA interference-mediated knockdown of hsp-90 expression partially phenocopied hsp-90(om40), confirming the loss-of-function nature ofhsp-90(om40). Furthermore, reduced HSP-90 activity enhanced the effect of reduced function of both the GLP-1 receptor and thedownstream LAG-1 transcription factor. Taken together, our results provide the first experimental evidence of an essential role for HSP90 inNotch signaling in development

    Hospitalization-Associated Change in Gait Speed and Risk of Functional Limitations for Older Adults

    Get PDF
    BACKGROUND: Hospitalization-associated functional decline is a common problem for older adults, but it is unclear how hospitalizations affect physical performance measures such as gait speed. We sought to determine hospitalization-associated change in gait speed and likelihood of new limitations in mobility and activities of daily living (ADLs). METHODS: We used longitudinal data over 5 years from the Health, Aging and Body Composition Study, a prospective cohort of black and white community-dwelling men and women, aged 70-79 years, who had no limitations in mobility (difficulty walking 1/4 mile or climbing 10 steps) or ADLs (transferring, bathing, dressing, and eating) at baseline. Gait speed, and new self-reported limitations in mobility and ADLs were assessed annually. Selected participants (n = 2,963) had no limitations at the beginning of each 1-year interval. Hospitalizations were self-reported every 6 months and verified with medical record data. Generalized estimating equations were used to examine hospitalization-associated change in gait speed and odds of new limitations over each 1-year interval. Fully adjusted models included demographics, hospitalization within the past year, health conditions, symptoms, body mass index, and health-related behaviors. RESULTS: In fully adjusted models, any hospitalization was associated with decrease in gait speed (-0.04 m/s; 95% confidence interval [CI]: -0.05 to -0.03) and higher odds of new limitations in mobility or ADLs (odds ratio = 1.97, 95% CI: 1.70-2.28), and separately with increased odds of new mobility limitation (odds ratio = 2.22, 95% CI: 1.90-2.60) and new ADL limitations (odds ratio = 1.84, 95% CI: 1.53-2.21). Multiple hospitalizations within a year were associated with gait speed decline (-0.06 m/s; 95% CI: -0.08 to -0.04) and greater odds of new limitations in mobility or ADLs (odds ratio = 2.96, 95% CI: 2.23-3.95). CONCLUSIONS: Functionally independent older adults experienced hospitalization-associated declines in gait speed and new limitations in mobility and ADLs

    Health and function of participants in the Long Life Family Study: A comparison with other cohorts

    Get PDF
    Individuals from families recruited for the Long Life Family Study (LLFS) (n= 4559) were examined and compared to individuals from other cohorts to determine whether the recruitment targeting longevity resulted in a cohort of individuals with better health and function. Other cohorts with similar data included the Cardiovascular Health Study, the Framingham Heart Study, and the New England Centenarian Study. Diabetes, chronic pulmonary disease and peripheral artery disease tended to be less common in LLFS probands and offspring compared to similar aged persons in the other cohorts. Pulse pressure and triglycerides were lower, high density lipids were higher, and a perceptual speed task and gait speed were better in LLFS. Age-specific comparisons showed differences that would be consistent with a higher peak, later onset of decline or slower rate of change across age in LLFS participants. These findings suggest several priority phenotypes for inclusion in future genetic analysis to identify loci contributing to exceptional survival
    corecore