102 research outputs found
Application of Item Response Theory to Modeling of Expanded Disability Status Scale in Multiple Sclerosis.
In this study, we report the development of the first item response theory (IRT) model within a pharmacometrics framework to characterize the disease progression in multiple sclerosis (MS), as measured by Expanded Disability Status Score (EDSS). Data were collected quarterly from a 96-week phase III clinical study by a blinder rater, involving 104,206 item-level observations from 1319 patients with relapsing-remitting MS (RRMS), treated with placebo or cladribine. Observed scores for each EDSS item were modeled describing the probability of a given score as a function of patients' (unobserved) disability using a logistic model. Longitudinal data from placebo arms were used to describe the disease progression over time, and the model was then extended to cladribine arms to characterize the drug effect. Sensitivity with respect to patient disability was calculated as Fisher information for each EDSS item, which were ranked according to the amount of information they contained. The IRT model was able to describe baseline and longitudinal EDSS data on item and total level. The final model suggested that cladribine treatment significantly slows disease-progression rate, with a 20% decrease in disease-progression rate compared to placebo, irrespective of exposure, and effects an additional exposure-dependent reduction in disability progression. Four out of eight items contained 80% of information for the given range of disabilities. This study has illustrated that IRT modeling is specifically suitable for accurate quantification of disease status and description and prediction of disease progression in phase 3 studies on RRMS, by integrating EDSS item-level data in a meaningful manner.Pharmacolog
Reconstruction of cell population dynamics using CFSE
Background: Quantifying cell division and death is central to many studies in the biological
sciences. The fluorescent dye CFSE allows the tracking of cell division in vitro and in vivo and
provides a rich source of information with which to test models of cell kinetics. Cell division and
death have a stochastic component at the single-cell level, and the probabilities of these occurring
in any given time interval may also undergo systematic variation at a population level. This gives rise
to heterogeneity in proliferating cell populations. Branching processes provide a natural means of
describing this behaviour.
Results: We present a likelihood-based method for estimating the parameters of branching
process models of cell kinetics using CFSE-labeling experiments, and demonstrate its validity using
synthetic and experimental datasets. Performing inference and model comparison with real CFSE
data presents some statistical problems and we suggest methods of dealing with them.
Conclusion: The approach we describe here can be used to recover the (potentially variable)
division and death rates of any cell population for which division tracking information is available
Is Canada ready for patient accessible electronic health records? A national scan
<p>Abstract</p> <p>Background</p> <p>Access to personal health information through the electronic health record (EHR) is an innovative means to enable people to be active participants in their own health care. Currently this is not an available option for consumers of health. The absence of a key technology, the EHR, is a significant obstacle to providing patient accessible electronic records. To assess the readiness for the implementation and adoption of EHRs in Canada, a national scan was conducted to determine organizational readiness and willingness for patient accessible electronic records.</p> <p>Methods</p> <p>A survey was conducted of Chief Executive Officers (CEOs) of Canadian public and acute care hospitals.</p> <p>Results</p> <p>Two hundred thirteen emails were sent to CEOs of Canadian general and acute care hospitals, with a 39% response rate. Over half (54.2%) of hospitals had some sort of EHR, but few had a record that was predominately electronic. Financial resources were identified as the most important barrier to providing patients access to their EHR and there was a divergence in perceptions from healthcare providers and what they thought patients would want in terms of access to the EHR, with providers being less willing to provide access and patients desire for greater access to the full record.</p> <p>Conclusion</p> <p>As the use of EHRs becomes more commonplace, organizations should explore the possibility of responding to patient needs for clinical information by providing access to their EHR. The best way to achieve this is still being debated.</p
Useful pharmacodynamic endpoints in children: selection, measurement, and next steps.
Pharmacodynamic (PD) endpoints are essential for establishing the benefit-to-risk ratio for therapeutic interventions in children and neonates. This article discusses the selection of an appropriate measure of response, the PD endpoint, which is a critical methodological step in designing pediatric efficacy and safety studies. We provide an overview of existing guidance on the choice of PD endpoints in pediatric clinical research. We identified several considerations relevant to the selection and measurement of PD endpoints in pediatric clinical trials, including the use of biomarkers, modeling, compliance, scoring systems, and validated measurement tools. To be useful, PD endpoints in children need to be clinically relevant, responsive to both treatment and/or disease progression, reproducible, and reliable. In most pediatric disease areas, this requires significant validation efforts. We propose a minimal set of criteria for useful PD endpoint selection and measurement. We conclude that, given the current heterogeneity of pediatric PD endpoint definitions and measurements, both across and within defined disease areas, there is an acute need for internationally agreed, validated, and condition-specific pediatric PD endpoints that consider the needs of all stakeholders, including healthcare providers, policy makers, patients, and families.Pediatric Research advance online publication, 11 April 2018; doi:10.1038/pr.2018.38
Users' perspectives of barriers and facilitators to implementing EHR in Canada: A study protocol
<p>Abstract</p> <p>Background</p> <p>In Canada, federal, provincial, and territorial governments are developing an ambitious project to implement an interoperable electronic health record (EHR). Benefits for patients, healthcare professionals, organizations, and the public in general are expected. However, adoption of an interoperable EHR remains an important issue because many previous EHR projects have failed due to the lack of integration into practices and organizations. Furthermore, perceptions of the EHR vary between end-user groups, adding to the complexity of implementing this technology. Our aim is to produce a comprehensive synthesis of actual knowledge on the barriers and facilitators influencing the adoption of an interoperable EHR among its various users and beneficiaries.</p> <p>Methods</p> <p>First, we will conduct a comprehensive review of the scientific literature and other published documentation on the barriers and facilitators to the implementation of the EHR. Standardized literature search and data extraction methods will be used. Studies' quality and relevance to inform decisions on EHR implementation will be assessed. For each group of EHR users identified, barriers and facilitators will be categorized and compiled using narrative synthesis and meta-analytical techniques. The principal factors identified for each group of EHR users will then be validated for its applicability to various Canadian contexts through a two-round Delphi study, involving representatives from each end-user groups. Continuous exchanges with decision makers and periodic knowledge transfer activities are planned to facilitate the dissemination and utilization of research results in policies regarding the implementation of EHR in the Canadian healthcare system.</p> <p>Discussion</p> <p>Given the imminence of an interoperable EHR in Canada, knowledge and evidence are urgently needed to prepare this major shift in our healthcare system and to oversee the factors that could affect its adoption and integration by all its potential users. This synthesis will be the first to systematically summarize the barriers and facilitators to EHR adoption perceived by different groups and to consider the local contexts in order to ensure the applicability of this knowledge to the particular realities of various Canadian jurisdictions. This comprehensive and rigorous strategy could be replicated in other settings.</p
Multi-level analysis of electronic health record adoption by health care professionals: A study protocol
<p>Abstract</p> <p>Background</p> <p>The electronic health record (EHR) is an important application of information and communication technologies to the healthcare sector. EHR implementation is expected to produce benefits for patients, professionals, organisations, and the population as a whole. These benefits cannot be achieved without the adoption of EHR by healthcare professionals. Nevertheless, the influence of individual and organisational factors in determining EHR adoption is still unclear. This study aims to assess the unique contribution of individual and organisational factors on EHR adoption in healthcare settings, as well as possible interrelations between these factors.</p> <p>Methods</p> <p>A prospective study will be conducted. A stratified random sampling method will be used to select 50 healthcare organisations in the Quebec City Health Region (Canada). At the individual level, a sample of 15 to 30 health professionals will be chosen within each organisation depending on its size. A semi-structured questionnaire will be administered to two key informants in each organisation to collect organisational data. A composite adoption score of EHR adoption will be developed based on a Delphi process and will be used as the outcome variable. Twelve to eighteen months after the first contact, depending on the pace of EHR implementation, key informants and clinicians will be contacted once again to monitor the evolution of EHR adoption. A multilevel regression model will be applied to identify the organisational and individual determinants of EHR adoption in clinical settings. Alternative analytical models would be applied if necessary.</p> <p>Results</p> <p>The study will assess the contribution of organisational and individual factors, as well as their interactions, to the implementation of EHR in clinical settings.</p> <p>Conclusions</p> <p>These results will be very relevant for decision makers and managers who are facing the challenge of implementing EHR in the healthcare system. In addition, this research constitutes a major contribution to the field of knowledge transfer and implementation science.</p
Comparison of user groups' perspectives of barriers and facilitators to implementing electronic health records: a systematic review
<p>Abstract</p> <p>Background</p> <p>Electronic health record (EHR) implementation is currently underway in Canada, as in many other countries. These ambitious projects involve many stakeholders with unique perceptions of the implementation process. EHR users have an important role to play as they must integrate the EHR system into their work environments and use it in their everyday activities. Users hold valuable, first-hand knowledge of what can limit or contribute to the success of EHR implementation projects. A comprehensive synthesis of EHR users' perceptions is key to successful future implementation. This systematic literature review was aimed to synthesize current knowledge of the barriers and facilitators influencing shared EHR implementation among its various users.</p> <p>Methods</p> <p>Covering a period from 1999 to 2009, a literature search was conducted on nine electronic databases. Studies were included if they reported on users' perceived barriers and facilitators to shared EHR implementation, in healthcare settings comparable to Canada. Studies in all languages with an empirical study design were included. Quality and relevance of the studies were assessed. Four EHR user groups were targeted: physicians, other health care professionals, managers, and patients/public. Content analysis was performed independently by two authors using a validated extraction grid with pre-established categorization of barriers and facilitators for each group of EHR users.</p> <p>Results</p> <p>Of a total of 5,695 potentially relevant publications identified, 117 full text publications were obtained after screening titles and abstracts. After review of the full articles, 60 publications, corresponding to 52 studies, met the inclusion criteria. The most frequent adoption factors common to all user groups were design and technical concerns, ease of use, interoperability, privacy and security, costs, productivity, familiarity and ability with EHR, motivation to use EHR, patient and health professional interaction, and lack of time and workload. Each user group also identified factors specific to their professional and individual priorities.</p> <p>Conclusions</p> <p>This systematic review presents innovative research on the barriers and facilitators to EHR implementation. While important similarities between user groups are highlighted, differences between them demonstrate that each user group also has a unique perspective of the implementation process that should be taken into account.</p
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