Project description:BackgroundDiscrete choice experiments have become a popular study design to study the labour market preferences of health workers. Discrete choice experiments in health, however, have been criticised for lagging behind best practice and there are specific methodological considerations for those focused on job choices. We performed a systematic review of the application of discrete choice experiments to inform health workforce policy.MethodsWe searched for discrete choice experiments that examined the labour market preferences of health workers, including doctors, nurses, allied health professionals, mid-level and community health workers. We searched Medline, Embase, Global Health, other databases and grey literature repositories with no limits on date or language and contacted 44 experts. Features of choice task and experimental design, conduct and analysis of included studies were assessed against best practice. An assessment of validity was undertaken for all studies, with a comparison of results from those with low risk of bias and a similar objective and context.ResultsTwenty-seven studies were included, with over half set in low- and middle-income countries. There were more studies published in the last four years than the previous ten years. Doctors or medical students were the most studied cadre. Studies frequently pooled results from heterogeneous subgroups or extrapolated these results to the general population. Only one third of studies included an opt-out option, despite all health workers having the option to exit the labour market. Just five studies combined results with cost data to assess the cost effectiveness of various policy options. Comparison of results from similar studies broadly showed the importance of bonus payments and postgraduate training opportunities and the unpopularity of time commitments for the uptake of rural posts.ConclusionsThis is the first systematic review of discrete choice experiments in human resources for health. We identified specific issues relating to this application of which practitioners should be aware to ensure robust results. In particular, there is a need for more defined target populations and increased synthesis with cost data. Research on a wider range of health workers and the generalisability of results would be welcome to better inform policy.
Project description:IntroductionRecent evidence suggests that choice of fluid used for resuscitation may influence mortality in critically ill patients.MethodsWe conducted a cross-sectional study in 391 intensive care units across 25 countries to describe the types of fluids administered during resuscitation episodes. We used generalized estimating equations to examine the association between patient, prescriber and geographic factors and the type of fluid administered (classified as crystalloid, colloid or blood products).ResultsDuring the 24-hour study period, 1,955 of 5,274 (37.1%) patients received resuscitation fluid during 4,488 resuscitation episodes. The main indications for administering crystalloid or colloid were impaired perfusion (1,526/3,419 (44.6%) of episodes), or to correct abnormal vital signs (1,189/3,419 (34.8%)). Overall, colloid was administered to more patients (1,234 (23.4%) versus 782 (14.8%)) and during more episodes (2,173 (48.4%) versus 1,468 (32.7%)) than crystalloid. After adjusting for patient and prescriber characteristics, practice varied significantly between countries with country being a strong independent determinant of the type of fluid prescribed. Compared to Canada where crystalloid, colloid and blood products were administered in 35.5%, 40.6% and 28.3% of resuscitation episodes respectively, odds ratios for the prescription of crystalloid in China, Great Britain and New Zealand were 0.46 (95% confidence interval (CI) 0.30 to 0.69), 0.18 (0.10 to 0.32) and 3.43 (1.71 to 6.84) respectively; odds ratios for the prescription of colloid in China, Great Britain and New Zealand were 1.72 (1.20 to 2.47), 4.72 (2.99 to 7.44) and 0.39 (0.21 to 0.74) respectively. In contrast, choice of fluid was not influenced by measures of illness severity (for example, Acute Physiology and Chronic Health Evaluation (APACHE) II score).ConclusionsAdministration of resuscitation fluid is a common intervention in intensive care units and choice of fluid varies markedly between countries. Although colloid solutions are more expensive and may possibly be harmful in some patients, they were administered to more patients and during more resuscitation episodes than crystalloids were.
Project description:Gene expression microarrays have made a profound impact in biomedical research. The diversity of platforms and analytical methods has made comparison of data from multiple platforms very challenging. In this study, we describe a framework for comparisons across platforms and laboratories. We have attempted to include nearly all the available commercial and “in-house” platforms. Using probe sequences matched at the exon level improved consistency of measurements across the different microarray platforms compared to annotation-based matches. Generally, consistency was good for highly expressed genes, and variable for genes with lower expression values as confirmed by QRT-PCR. Concordance of measurements was higher between laboratories on the same platform than across platforms. We demonstrate that, after stringent pre-processing, commercial arrays were more consistent than “in-house” arrays, and by most measures, one-dye platforms were more consistent than two-dye platforms. Keywords: cross platform microarrays
Project description:An important factor for successful translational stroke research is study quality. Low-quality studies are at risk of biased results and effect overestimation, as has been intensely discussed for small animal stroke research. However, little is known about the methodological rigor and quality in large animal stroke models, which are becoming more frequently used in the field. Based on research in two databases, this systematic review surveys and analyses the methodological quality in large animal stroke research. Quality analysis was based on the Stroke Therapy Academic Industry Roundtable and the Animals in Research: Reporting In Vivo Experiments guidelines. Our analysis revealed that large animal models are utilized with similar shortcomings as small animal models. Moreover, translational benefits of large animal models may be limited due to lacking implementation of important quality criteria such as randomization, allocation concealment, and blinded assessment of outcome. On the other hand, an increase of study quality over time and a positive correlation between study quality and journal impact factor were identified. Based on the obtained findings, we derive recommendations for optimal study planning, conducting, and data analysis/reporting when using large animal stroke models to fully benefit from the translational advantages offered by these models.
Project description:ObjectiveTo examine concordance between treatment effects in animal experiments and clinical trials. Study design Systematic review.Data sourcesMedline, Embase, SIGLE, NTIS, Science Citation Index, CAB, BIOSIS.Study selectionAnimal studies for interventions with unambiguous evidence of a treatment effect (benefit or harm) in clinical trials: head injury, antifibrinolytics in haemorrhage, thrombolysis in acute ischaemic stroke, tirilazad in acute ischaemic stroke, antenatal corticosteroids to prevent neonatal respiratory distress syndrome, and bisphosphonates to treat osteoporosis. Review methods Data were extracted on study design, allocation concealment, number of randomised animals, type of model, intervention, and outcome.ResultsCorticosteroids did not show any benefit in clinical trials of treatment for head injury but did show a benefit in animal models (pooled odds ratio for adverse functional outcome 0.58, 95% confidence interval 0.41 to 0.83). Antifibrinolytics reduced bleeding in clinical trials but the data were inconclusive in animal models. Thrombolysis improved outcome in patients with ischaemic stroke. In animal models, tissue plasminogen activator reduced infarct volume by 24% (95% confidence interval 20% to 28%) and improved neurobehavioural scores by 23% (17% to 29%). Tirilazad was associated with a worse outcome in patients with ischaemic stroke. In animal models, tirilazad reduced infarct volume by 29% (21% to 37%) and improved neurobehavioural scores by 48% (29% to 67%). Antenatal corticosteroids reduced respiratory distress and mortality in neonates whereas in animal models respiratory distress was reduced but the effect on mortality was inconclusive (odds ratio 4.2, 95% confidence interval 0.85 to 20.9). Bisphosphonates increased bone mineral density in patients with osteoporosis. In animal models the bisphosphonate alendronate increased bone mineral density compared with placebo by 11.0% (95% confidence interval 9.2% to 12.9%) in the combined results for the hip region. The corresponding treatment effect in the lumbar spine was 8.5% (5.8% to 11.2%) and in the combined results for the forearms (baboons only) was 1.7% (-1.4% to 4.7%).ConclusionsDiscordance between animal and human studies may be due to bias or to the failure of animal models to mimic clinical disease adequately.
Project description:Sepsis is a common and life-threatening inflammatory response to severe infection treated with antibiotics and fluid resuscitation. Despite the central role of intravenous fluid in sepsis management, fundamental questions regarding which fluid and in what amount remain unanswered. Recent advances in understanding the physiologic response to fluid administration, and large clinical studies examining resuscitation strategies, fluid balance after resuscitation, colloid versus crystalloid solutions, and high- versus low-chloride crystalloids, inform the current approach to sepsis fluid management and suggest areas for future research.
Project description:Translation from preclinical animal research to clinical bedside has proven to be difficult to impossible in many fields of research (e.g. acute stroke, ALS and HIV vaccination development) with oncology showing particularly low translation rates (5% vs. 20% for cardiovascular diseases). Several investigations on published preclinical animal research have revealed that apart from plain species differences, translational problems can arise from low study quality (e.g. study design) or non-representative experimental conditions (e.g. treatment schedule). This review assessed the published experimental circumstances and quality of anti-angiogenic cancer drug development in 232 in vivo studies. The quality of study design was often insufficient; at least the information published about the experiments was not satisfactory in most cases. There was no quality improvement over time, with the exception of conflict of interest statements. This increase presumably arose mainly because journal guidelines request such statements more often recently. Visual inspection of data and a cluster analysis confirmed a trend described in literature that low study quality tends to overestimate study outcome. It was also found that experimental outcome was more favorable when a potential drug was investigated as the main focus of a study, compared to drugs that were used as comparison interventions. We assume that this effect arises from the frequent neglect of blinding investigators towards treatment arms and refer to it as hypothesis bias. In conclusion, the reporting and presumably also the experimental performance of animal studies in drug development for oncology suffer from similar shortcomings as other fields of research (such as stroke or ALS). We consider it necessary to enforce experimental quality and reporting that corresponds to the level of clinical studies. It seems that only clear journal guidelines or guidelines from licensing authorities, where failure to fulfill prevents publication or experimental license, can help to improve this situation.
Project description:BackgroundThe purpose of our study was to explore the effect of nitrogen-containing bisphosphonate (N-BP) on vascular calcification (VC) through animal experiments and a meta-analysis.MethodsIn our animal experiments, Sprague-Dawley (SD) rats were randomly divided into a control group, a VC group, a low-dose zoledronic acid (ZOL) (20 µg/kg) group and a high-dose ZOL (100 µg/kg) group. The calcification of the aortic arch was observed by alizarin red staining. The calcium content of the aortic arch was measured. In our systematic review and meta-analysis, databases, including PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI), and the Wanfang database, were searched from their inception to December 20, 2023. Eligible studies comparing N-BP versus no N-BP in the treatment of VC were included.ResultsIn our animal experiment, the red-stained calcification structure in the low-dose ZOL group was slightly reduced and the red-stained calcification structure in the high-dose ZOL group was significantly reduced compared with that in the VC. The calcium content in the low-dose ZOL group was slightly lower than that in the VC group, but the difference was not significant (P = 0.08). The calcium content in the high-dose ZOL group was significantly lower than that in the VC group (P < 0.0001). Our meta-analysis of human studies revealed that N-BP did not reduce the arterial calcification score (P = 0.46). Our meta-analysis of animal studies revealed that N-BP did not significantly reduce the arterial calcification score (P = 0.09), but N-BP reduced the arterial calcification area (P < 0.00001), arterial calcium content (P = 0.009) and PO4 content (P = 0.0001).ConclusionsOur animal experiment revealed that high-dose ZOL inhibited VC, but low-dose ZOL did not significantly inhibit VC. Our meta-analysis of human studies revealed that N-BP was not effective in the treatment of VC, but our meta-analysis of animal studies suggested a role of N-BP in inhibiting VC.
Project description:The administration of intravenous fluid to critically ill patients is one of the most common, but also one of the most fiercely debated, interventions in intensive care medicine. Even though many thousands of patients have been enrolled in large trials of alternative fluid strategies, consensus remains elusive and practice is widely variable. Critically ill patients are significantly heterogeneous, making a one size fits all approach unlikely to be successful.New data from basic, animal, and clinical research suggest that fluid resuscitation could be associated with significant harm. There are several important limitations and concerns regarding fluid bolus therapy as it is currently being used in clinical practice. These include, but are not limited to: the lack of an agreed definition; limited and short-lived physiological effects; no evidence of an effect on relevant patient outcomes; and the potential to contribute to fluid overload, specifically when fluid responsiveness is not assessed and when targets and safety limits are not used.Fluid administration in critically ill patients requires clinicians to integrate abnormal physiological parameters into a clinical decision-making model that also incorporates the likely diagnosis and the likely risk or benefit in the specific patient's context. Personalised fluid resuscitation requires careful attention to the mnemonic CIT TAIT: context, indication, targets, timing, amount of fluid, infusion strategy, and type of fluid.The research agenda should focus on experimental and clinical studies to: improve our understanding of the physiological effects of fluid infusion, e.g. on the glycocalyx; evaluate new types of fluids; evaluate novel fluid minimisation protocols; study the effects of a no-fluid strategy for selected patients and scenarios; and compare fluid therapy with other interventions. The adaptive platform trial design may provide us with the tools to evaluate these types of interventions in the intrinsically heterogeneous intensive care unit population, accounting for the explicit assumption that treatment effects may be heterogeneous.
Project description:BackgroundThe long-term aim of developing laser based particle acceleration towards clinical application requires not only substantial technological progress, but also the radiobiological characterization of the resulting ultra-short and ultra-intensive particle beam pulses. After comprehensive cell studies a mouse ear tumour model was established allowing for the penetration of low energy protons (~20 MeV) currently available at laser driven accelerators. The model was successfully applied for a first tumour growth delay study with laser driven electrons, whereby the need of improvements crop out.MethodsTo optimise the mouse ear tumour model with respect to a stable, high take rate and a lower number of secondary tumours, Matrigel was introduced for tumour cell injection. Different concentrations of two human tumour cell lines (FaDu, LN229) and Matrigel were evaluated for stable tumour growth and fulfilling the allocation criteria for irradiation experiments. The originally applied cell injection with PBS was performed for comparison and to assess the long-term stability of the model. Finally, the optimum suspension of cells and Matrigel was applied to determine applicable dose ranges for tumour growth delay studies by 200 kV X-ray irradiation.ResultsBoth human tumour models showed a high take rate and exponential tumour growth starting at a volume of ~10 mm3. As disclosed by immunofluorescence analysis these small tumours already interact with the surrounding tissue and activate endothelial cells to form vessels. The formation of delimited, solid tumours at irradiation size was shown by standard H&E staining and a realistic dose range for inducing tumour growth delay without permanent tumour control was obtained for both tumour entities.ConclusionThe already established mouse ear tumour model was successfully upgraded now providing stable tumour growth with high take rate for two tumour entities (HNSCC, glioblastoma) that are of interest for future irradiation experiments at experimental accelerators.