BackgroundIn 1999 a four-level hierarchy of evidence was promoted by the National Health and Medical Research Council in Australia. The primary purpose of this hierarchy was to assist with clinical practice guideline development, although it was co-opted for use in systematic literature reviews and health technology assessments. In this hierarchy interventional study designs were ranked according to the likelihood that bias had been eliminated and thus it was not ideal to assess studies that addressed other types of clinical questions. This paper reports on the revision and extension of this evidence hierarchy to enable broader use within existing evidence assessment systems.MethodsA working party identified and assessed empirical evidence, and used a commissioned review of existing evidence assessment schema, to support decision-making regarding revision of the hierarchy. The aim was to retain the existing evidence levels I-IV but increase their relevance for assessing the quality of individual diagnostic accuracy, prognostic, aetiologic and screening studies. Comprehensive public consultation was undertaken and the revised hierarchy was piloted by individual health technology assessment agencies and clinical practice guideline developers. After two and a half years, the hierarchy was again revised and commenced a further 18 month pilot period.ResultsA suitable framework was identified upon which to model the revision. Consistency was maintained in the hierarchy of "levels of evidence" across all types of clinical questions; empirical evidence was used to support the relationship between study design and ranking in the hierarchy wherever possible; and systematic reviews of lower level studies were themselves ascribed a ranking. The impact of ethics on the hierarchy of study designs was acknowledged in the framework, along with a consideration of how harms should be assessed.ConclusionThe revised evidence hierarchy is now widely used and provides a common standard against which to initially judge the likelihood of bias in individual studies evaluating interventional, diagnostic accuracy, prognostic, aetiologic or screening topics. Detailed quality appraisal of these individual studies, as well as grading of the body of evidence to answer each clinical, research or policy question, can then be undertaken as required.
Effective off-loading is considered to be an important part of the successful clinical management of diabetic foot ulcers. The aim of this systematic review is to investigate the safety and effectiveness of different off-loading devices for the treatment of diabetic foot ulcers. The medical literature was extensively searched from January 1966 to May 2012. Systematic reviews and controlled studies that compared the use of different off-loading devices formed the evidence base. Studies were critically appraised to determine their risk of methodological bias, and data were extracted. Results were pooled using random effects meta-analysis and tested for heterogeneity. When compared with removable devices, non-removable off-loading devices were found, on average, to be more effective at promoting the healing of diabetic foot ulcers (RRp = 1.43; 95% CI 1.11, 1.84; I(2) = 66.9%; p = 0.001; k = 10). Analysis, stratified by type of removable device, did not detect a statistically significant difference between non-removable off-loading devices and removable cast walkers; however, on average non-removable off-loading devices performed better than therapeutic shoes at promoting the healing of diabetic foot ulcers (RRp = 1.68; 95% CI 1.09, 2.58; I(2) = 71.5%; p = 0.004; k = 6). The two types of non-removable off-loading devices i.e. total contact casts and instant total contact casts (removable cast walker rendered irremovable by securing with bandage or lace), were found to be equally effective (RRp = 1.06; 95% CI 0.88, 1.27; I(2) = 3.3%; p = 0.31; k = 2). In conclusion, non-removable off-loading devices regardless of type, are more likely to result in ulcer healing than removable off-loading devices, presumably because patient compliance with off-loading is facilitated.
From the low-level evidence available it seems that EVLT benefits most patients in the short term, but rates of recanalization, re-treatment, occlusion and reflux may alter with longer follow-up. The lack of such data, in addition to the small numbers of patients in the available studies, demonstrates the need for a randomized clinical trial of EVLT versus conventional surgery.
Health systems can be improved appreciably by making them more efficient and accountable, and enhancing the quality of care, without necessarily requiring additional resources. Australia, like other nations, cannot escape making difficult health care choices in the context of resource scarcity, and the challenge of delivering quality care, informed by best available evidence, to an ageing population with multiple comorbidities. An opportunity exists for a cost‐saving or cost‐neutral agenda of reallocation of resources within the existing health budget, through reducing the use of existing health care interventions that offer little or no benefit relative to the cost of their public subsidy. This would allow reallocation of funding towards interventions that are more cost‐effective, maximising health gain. Criteria based on those developed for health technology assessment (HTA) might facilitate the systematic and transparent identification of existing, potentially ineffective practices on which to prioritise candidates for assessment as to their cost‐effectiveness. The process could be jointly funded by all relevant stakeholders but centrally administered, with HTA groups resourced to undertake identification and assessment and to liaise with clinicians, consumers and funding stakeholders.
BackgroundClinical practice guidelines are an important element of evidence-based practice. Considering an often complicated body of evidence can be problematic for guideline developers, who in the past may have resorted to using levels of evidence of individual studies as a quasi-indicator for the strength of a recommendation. This paper reports on the production and trial of a methodology and associated processes to assist Australian guideline developers in considering a body of evidence and grading the resulting guideline recommendations.MethodsIn recognition of the complexities of clinical guidelines and the multiple factors that influence choice in health care, a working group of experienced guideline consultants was formed under the auspices of the Australian National Health and Medical Research Council (NHMRC) to produce and pilot a framework to formulate and grade guideline recommendations. Consultation with national and international experts and extensive piloting informed the process.ResultsThe FORM framework consists of five components (evidence base, consistency, clinical impact, generalisability and applicability) which are used by guideline developers to structure their decisions on how to convey the strength of a recommendation through wording and grading via a considered judgement form. In parallel (but separate from the grading process) guideline developers are asked to consider implementation implications for each recommendation.ConclusionsThe framework has now been widely adopted by Australian guideline developers who find it to be a logical and intuitive way to formulate and grade recommendations in clinical practice guidelines.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.