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1.
Bone Joint Res ; 13(5): 201-213, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38688503

RESUMEN

Aims: The aims of this study were to identify and evaluate the current literature examining the prognostic factors which are associated with failure of total elbow arthroplasty (TEA). Methods: Electronic literature searches were conducted using MEDLINE, Embase, PubMed, and Cochrane. All studies reporting prognostic estimates for factors associated with the revision of a primary TEA were included. The risk of bias was assessed using the Quality In Prognosis Studies (QUIPS) tool, and the quality of evidence was assessed using the modified Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. Due to low quality of the evidence and the heterogeneous nature of the studies, a narrative synthesis was used. Results: A total of 19 studies met the inclusion criteria, investigating 28 possible prognostic factors. Most QUIPS domains (84%) were rated as moderate to high risk of bias. The quality of the evidence was low or very low for all prognostic factors. In low-quality evidence, prognostic factors with consistent associations with failure of TEA in more than one study were: the sequelae of trauma leading to TEA, either independently or combined with acute trauma, and male sex. Several other studies investigating sex reported no association. The evidence for other factors was of very low quality and mostly involved exploratory studies. Conclusion: The current evidence investigating the prognostic factors associated with failure of TEA is of low or very low quality, and studies generally have a moderate to high risk of bias. Prognostic factors are subject to uncertainty, should be interpreted with caution, and are of little clinical value. Higher-quality evidence is required to determine robust prognostic factors for failure of TEA.

2.
Emerg Med J ; 41(1): 51-59, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-37827821

RESUMEN

BACKGROUND: Health coaching services could help to reduce emergency healthcare utilisation for patients targeted proactively by a clinical prediction model (CPM) predicting patient likelihood of future hospitalisations. Such interventions are designed to empower patients to confidently manage their own health and effectively utilise wider resources. Using CPMs to identify patients, rather than prespecified criteria, accommodates for the dynamic hospital user population and for sufficient time to provide preventative support. However, it is unclear how this care model would negatively impact survival. METHODS: Emergency Department (ED) attenders and hospital inpatients between 2015 and 2019 were automatically screened for their risk of hospitalisation within 6 months of discharge using a locally trained CPM on routine data. Those considered at risk and screened as suitable for the intervention were contacted for consent and randomised to one-to-one telephone health coaching for 4-6 months, led by registered health professionals, or routine care with no contact after randomisation. The intervention involved motivational guidance, support for self-care, health education, and coordination of social and medical services. Co-primary outcomes were emergency hospitalisation and ED attendances, which will be reported separately. Mortality at 24 months was a safety endpoint. RESULTS: Analysis among 1688 consented participants (35% invitation rate from the CPM, median age 75 years, 52% female, 1139 intervention, 549 control) suggested no significant difference in overall mortality between treatment groups (HR (95% CI): 0.82 (0.62, 1.08), pr(HR<1=0.92), but did suggest a significantly lower mortality in men aged >75 years (HR (95% CI): 0.57 (0.37, 0.84), number needed to treat=8). Excluding one site unable to adopt a CPM indicated stronger impact for this patient subgroup (HR (95% CI): 0.45 (0.26, 0.76)). CONCLUSIONS: Early mortality in men aged >75 years may be reduced by supporting individuals at risk of unplanned hospitalisation with a clear outreach, out-of-hospital nurse-led, telephone-based coaching care model.


Asunto(s)
Modelos Estadísticos , Atención Secundaria de Salud , Masculino , Humanos , Femenino , Anciano , Pronóstico , Hospitalización , Alta del Paciente
3.
BMJ Open ; 13(8): e071705, 2023 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-37648384

RESUMEN

INTRODUCTION: Total elbow replacement (TER) has higher failure rates requiring revision surgery compared with the replacement of other joints. Understanding the factors associated with failure is essential for informed decision-making between patients and clinicians, and for reducing the failure rate. This review aims to identify, describe and appraise the literature examining prognostic factors for failure of TER. METHODS AND ANALYSIS: This systematic review will be conducted and reported in line with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines. Electronic literature searches will be conducted using Medline, EMBASE, PubMed and Cochrane. The search strategy will be broad, including a combination of subject headings (MESH) and free text search. This search will be supplemented with a screening of reference lists of the included studies and relevant reviews. Two independent reviewers will screen all search results in two stages (title and abstract, and full text) based on the Population, Index prognostic factor, Comparator prognostic factor, Outcome, Time and Setting criteria. The types of evidence included will be randomised trials, non-randomised trials, prospective and retrospective cohort studies, registry studies and case-control studies. If the literature lacks enough studies, then case series with 50 or more TERs will be considered for inclusion. Data extraction and risk of bias assessment for included studies will be performed by two independent reviewers using the Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies for Prognostic Factors and Quality In Prognostic Studies tools.Meta-analyses of prognostic estimates for each factor will be undertaken for studies that are deemed to be sufficiently robust and comparable. Several challenges are likely to arise due to heterogeneity between studies, therefore, subgroup and sensitivity analyses will be performed to account for the differences between studies. Heterogeneity will be assessed using Q and I2 statistics. If I2>40% then pooled estimates will not be reported. When quantitative synthesis is not possible, a narrative synthesis will be undertaken. The quality of the evidence for each prognostic factor will be assessed using the Grades of Recommendation Assessment, Development and Evaluation tool. PROSPERO REGISTRATION NUMBER: CRD42023384756.


Asunto(s)
Artroplastia de Reemplazo de Codo , Humanos , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Revisiones Sistemáticas como Asunto , Metaanálisis como Asunto , Literatura de Revisión como Asunto
4.
Diagn Progn Res ; 4: 9, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32671229

RESUMEN

BACKGROUND: Clinical prediction models (CPMs) predict the risk of health outcomes for individual patients. The majority of existing CPMs only harness cross-sectional patient information. Incorporating repeated measurements, such as those stored in electronic health records, into CPMs may provide an opportunity to enhance their performance. However, the number and complexity of methodological approaches available could make it difficult for researchers to explore this opportunity. Our objective was to review the literature and summarise existing approaches for harnessing repeated measurements of predictor variables in CPMs, primarily to make this field more accessible for applied researchers. METHODS: MEDLINE, Embase and Web of Science were searched for articles reporting the development of a multivariable CPM for individual-level prediction of future binary or time-to-event outcomes and modelling repeated measurements of at least one predictor. Information was extracted on the following: the methodology used, its specific aim, reported advantages and limitations, and software available to apply the method. RESULTS: The search revealed 217 relevant articles. Seven methodological frameworks were identified: time-dependent covariate modelling, generalised estimating equations, landmark analysis, two-stage modelling, joint-modelling, trajectory classification and machine learning. Each of these frameworks satisfies at least one of three aims: to better represent the predictor-outcome relationship over time, to infer a covariate value at a pre-specified time and to account for the effect of covariate change. CONCLUSIONS: The applicability of identified methods depends on the motivation for including longitudinal information and the method's compatibility with the clinical context and available patient data, for both model development and risk estimation in practice.

5.
J Clin Epidemiol ; 127: 191-197, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32726605

RESUMEN

BACKGROUND AND OBJECTIVE: In view of the growth of published articles, there is an increasing need for studies that summarize scientific research. An increasingly common review is a "methodology scoping review," which provides a summary of existing analytical methods, techniques and software that have been proposed or applied in research articles to address an analytical problem or further an analytical approach. However, guidelines for their design, implementation, and reporting are limited. METHODS: Drawing on the experiences of the authors, which were consolidated through a series of face-to-face workshops, we summarize the challenges inherent in conducting a methodology scoping review and offer suggestions of best practice to promote future guideline development. RESULTS: We identified three challenges of conducting a methodology scoping review. First, identification of search terms; one cannot usually define the search terms a priori, and the language used for a particular method can vary across the literature. Second, the scope of the review requires careful consideration because new methodology is often not described (in full) within abstracts. Third, many new methods are motivated by a specific clinical question, where the methodology may only be documented in supplementary materials. We formulated several recommendations that build upon existing review guidelines. These recommendations ranged from an iterative approach to defining search terms through to screening and data extraction processes. CONCLUSION: Although methodology scoping reviews are an important aspect of research, there is currently a lack of guidelines to standardize their design, implementation, and reporting. We recommend a wider discussion on this topic.


Asunto(s)
Proyectos de Investigación/normas , Literatura de Revisión como Asunto , Revisiones Sistemáticas como Asunto/métodos , Humanos
6.
Solid State Nucl Magn Reson ; 26(3-4): 153-9, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15388179

RESUMEN

17O NMR studies of various cation-exchanged LTA and LSX zeolites have shown similarities between the two systems. LSX samples containing divalent cations contain resonances with similar chemical shifts to those previously assigned to 'bare' framework oxygen atoms in Ca-LTA and Sr-LTA. The assignments are consistent with the trends seen in the spectra of monovalent cation-containing LSX and LTA zeolites, which show an increase in the average chemical shift with increasing cationic radius. The spectrum of Li-LSX, like Na-LSX, can be assigned based on the T-O-T bond angles. Gas sorption studies on Li-LSX are used to help identify the framework oxygen atoms that form the beta-cages and demonstrate the sensitivity of the (17)O shifts to gas loading.

7.
Chemistry ; 9(23): 5737-48, 2003 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-14673843

RESUMEN

The syntheses, structure solutions, and physicochemical and catalytic characterizations of the novel zeolites SSZ-53 and SSZ-59 are described. SSZ-53 and SSZ-59 were synthesized under hydrothermal conditions with the [1-(4-fluorophenyl)cyclopentylmethyl]trimethyl ammonium cation and 1-[1-(4-chlorophenyl)cyclopentylmethyl]-1-methyl azocanium cation, respectively, as structure-directing agents. The framework topology of SSZ-53 was solved with the FOCUS method, and the structure of SSZ-59 was determined by model building. Rietveld refinement of synchrotron X-ray powder diffraction data confirms each proposed model. SSZ-53 and SSZ-59 each possess a one-dimensional channel system delimited by 14-membered rings. Results from transmission electron microscopy, electron diffraction, catalytic experiments (spaciousness index and constraint index tests), and argon and hydrocarbon adsorption experiments are consistent with the proposed structures.

8.
J Am Chem Soc ; 125(14): 4342-9, 2003 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-12670258

RESUMEN

Powder and single-crystal X-ray diffraction, combined with MAS NMR measurements, has been used to study the thermal expansion of siliceous zeolite ferrierite as it approaches a second-order displacive phase transition from a low-symmetry (Pnnm) to a high-symmetry (Immm) structure. Below the transition temperature, ferrierite exhibits positive thermal expansivity. However, above the transition temperature a significant change in thermal behavior is seen, and ferrierite becomes a negative thermal expansion material. Accurate variable-temperature single-crystal X-ray diffraction measurements confirm the transition temperature and allow the changes in average atomic position to be followed with temperature. The results from the single-crystal X-ray diffraction study can be correlated with (29)Si MAS NMR chemical shifts for the low-temperature phase. At low temperatures the results show that the positive thermal expansivity is driven by an overall increase in Si[bond]Si distances related to an increase in Si[bond]O[bond]Si bond angles. However, in the high-temperature phase the Si[bond]O[bond]Si angles are approximately invariant with temperature, and the negative thermal expansion in this case is caused by transverse vibrations of the Si[bond]O[bond]Si units.

9.
J Am Chem Soc ; 125(6): 1633-42, 2003 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-12568625

RESUMEN

The synthesis, structure solution, and characterization of the novel zeolite SSZ-58 are described. SSZ-58 was synthesized under hydrothermal conditions using 1-butyl-1-cyclooctylpyrrolidinium cation as a structure-directing agent. The framework topology of SSZ-58 was determined with the FOCUS Fourier recycling method. SSZ-58 possesses 12 tetrahedral atoms in the asymmetric unit of its highest topological symmetry, and to date it is the most complex zeolite structure solved from powder data. Rietveld refinement of synchrotron powder X-ray diffraction data in space group Pmma confirmed the proposed model. SSZ-58 contains layers of atoms that are linked together by double five-membered rings (D5R), or 5(2)4(5) subunits, that have not been observed before in any zeolite or zeotype structures. SSZ-58 possesses a two-dimensional channel system consisting of 10-membered ring pores that intersect to form large cavities circumscribed by 12- and 16-membered ring pores.

10.
Angew Chem Int Ed Engl ; 37(12): 1711-1714, 1998 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-29711512

RESUMEN

A remarkable autofragmentation/rearrangement sequence results in the unprecedented formation of inorganic concave cyclic anion [(NiPS4 )3 ]3- (structure shown on the right) upon dissolving the potassium salt of the charged mineral polymer 1∞ [NiPS4 ]- in DMF; the initial complex fluid has a transient anisotropic texture that can be identified by optical microscopy under polarized light. In contrast, the complex fluid that results upon dissolving 1∞ [PdPS4 ]- is stable up to 323 K as persistent, flexible, charged chains.

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