Evidence based medicine

Evidence-based medicine (EBM) avoids reliance on instincts and experiences. Specialties many times interpret evidence-based practices in a manner most appropriate to their areas and create inconsistency of systems (Tables 13.8 through 13.11). 

Evidence-based medicine was defined by Sacked et al. (1996) as follows  

There are two components to evidence-based medicine and two related sets of responsibilities. The first component is clinical research. Clinical research is a scientific endeavor that provides evidence concerning potential therapeutic interventions. This book has focused on one particular therapeutic intervention, drug therapy. Once clinical trials have been conducted, the evidence obtained is published in clinical communications in journals. Everyone involved in clinical research has the responsibility to provide the best possible evidence in this manner. As noted throughout the book, this includes all aspects of clinical research study design, experimental methodology and clinical operations, analysis and interpretation, and also accurate and complete representation of study findings in clinical communications as discussed in Section 13.6. 

The second component of evidence-based medicine is clinical practice (see also Mayer, 2004 Straus et al., 2005). Clinicians have the responsibility of providing the best possible care to each of their individual patients. One part of being able to provide this optimum care is remaining aware of pertinent evidence that is published in clinical communications (as mentioned in the previous section, this is no small task). It is also incumbent on clinicians to be able to decide for themselves if the evidence presented in a clinical communication is good evidence and if the message of a systematic review or a meta-analysis is justified based on the quality of the report. As Katz (2001) commented  

Part of the burden for the responsible cultivation of higher standards and better outcomes in medicine falls, naturally, to researchers and those who screen and publish their findings. 

If our patient is older than, younger than, sicker than, healthier than, ethnically different from, taller, shorter, simply different from the subjects of a study, do the results pertain ...No degree of evidence will fully chart the expanse of idiosyncrasy in human health and disease. Thus, to work skillfully with evidence is to acknowledge its limits. All of the art and all of the science of medicine depends on how artfully and scientifically we as practitioners reach our decisions. The art of clinical decision making is judgment, an even more difficult concept to grapple with than evidence (pp. xi, xvii). 

Center for Reviews and Dissemination (CRD). University of York, York YOlO 5DD, U.K. Phone -1-44-1904-321-040, Fax +44-1904-321-041. E-mail crd york.ac.uk/inst/crd. URL http //www.york.ac.uk/inst/crd/. Established 1994. Aims to provide research-based information about the effects of interventions used in health and social care. CRD produces three databases Database of Abstracts of Reviews of Effects (DARE), NHS Economic Evaluation Database (NHS EED), 

National Institutes for Clinical Excellence (NICE). Midcity Place, 71 High Holbom, London WCIV 6NA, U.K Phone +44-20-7067-5800, Fax +44-20-7067-5801. E-mail nice nice.nhs.uk. URL http //www.nice.org.uk. Part of England s National Health Service, NICE was set up as a special health authority for England and Wales on April 1, 1999. Its goal is to provide refiable and authoritative best-practice guidelines for patients, health professionals, and the public. Complete published guidelines on cfinical practice and interventional procedures may be downloaded in PDF format from the NICE Web site. 

As health-care professionals we need to identify and solve the problem together with the patient, and we need to do it in a rational and cost-effective way. For a practitioner this is not easy based on the rapidly expanding progress within the medical area, increasing demand from patients, and the manipulation of information from various interests in the field. First we need drugs and other treatments with documented effects (efficacy) in the elderly. Then we need to select the most appropriate drug for the individual patient. The latter is complicated and evidence-based medicine (EBM) has been suggested as the method. Finally we need to communicate with the patient and establish a partnership (concordance). 

The main feature of the harmonisation is guidelines and Common Technical Documents (CTD). The CTD gives a harmonised format and content for new product applications and in 2003 there was an agreement on implementation, in USA, Europe and Japan. 

The ICH Topics are divided into four major categories. 

Good Clinical Practices, Clinical Safety Data Management) 

The efficacy document E7 (ICH 1993) states that the drug should be studied in all patient groups, elderly included, for which they have a significant utility. It also includes new uses, new formulations and new combinations of established medicinal products when there is specific reason to expect that conditions common in the elderly (e.g. renal or hepatic impairment, impaired cardiac function, concomitant illness or medication) are likely to be encountered. This also applies for when the geriatric patients response (safety, tolerability, efficacy) is different from the nongeriatrics.  

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The effect of statins on plasma lipids and lipoproteins is rapidly seen and fully achieved after 4-6 weeks of treatment. The effect persists unchanged during continued use for several years, but after stopping the diug, LDL-cholesterol rapidly increases to pretreatment levels. Treatment with statins is therefore usually continued indefinitely and not as a short-term cure. Finally, it is generally advisable to use the statins that have documented their efficacy in clinical trials (evidence-based medicine). 

Strength of recommendation A based on a meta-analysis or at least one randomized controlled trial. Strength of recommendation B based on at least one well-designed study, including case control and comparative studies. Strength of recommendation C based on expert reports or opinion (levels of evidence and strength of recommendation. Oxford (UK) Centre for Evidence-Based Medicine. Available at http //www.cebm.net/levels of evidence.asp (accessed December 8,2008). 

It is essential that, with the use of evidence-based medicine to inform decisions in health care, the processes used in program development be as transparent as possible. Information about the limited evidence and inherent uncertainty should be disclosed and available for scrutiny, even within the software itself. In fact, in an attempt to maximize transparency, some have advocated open source development and publication of interactive software models [49, 50]. Certainly, details of methodologies, sources, and other techniques employed for development of the underlying models must be acknowledged. However, the proprietary nature of many of these programs must be taken into consideration and measures put into place to ensure confidentiality. Requested publication of all NIH-sponsored research online (in PubMed) [51] within a reasonable time frame after journal acceptance will help to ensure that these data are available in the public domain in short order. 

As already outlined, health-care decision models hold little water in the sophisticated environment of evidence-based medicine. Nevertheless, two UK evaluations (Davies and Drummond, 1993 Matheson et al, 1994) do give some insight into the outcomes of using clozapine in the UK National Health Service, although model data were largely derived from the USA. 

Best Evidence. Best Evidence [43] combines more than 1200 abstracts and commentaries from ACP Journal Club and Evidence-Based Medicine (described below) and the full text of Diagnostic Strategies for Common Medical Problems, 2nd ed., together on a CD-ROM. It is commercially available. 

Evidence-Based Medicine. Evidence-Based Medicine [45] consists of summarized abstracts of articles on family medicine, internal medicine, general surgery, pediatrics, obstetrics, gynecology, psychiatry, and anesthesiology with commentary by clinical experts. More than 50 peer-reviewed medical journals are abstracted. Also included are key selections from ACP Journal Club. Evidence-Based Medicine is commercially available however, its distribution is restricted and does not include North, Central, or South America. 

Evidence-Based Medicine, [Internet]. URL http // www.acponline.org/catalog/journals/ebm.htm, accessed 10-14-2000. 

AL Dans, LF Dans, GH Guyatt, S Richardson. Users guides to the medical literature XIV. How to decide on the applicability of clinical trial results to your patient. Evidence-Based Medicine Working Group. JAMA 279 545-549, 1998. 

Managed healthcare systems also have interests in reductionist definitions of disease. The payment and reimbursement structures of Health Management Organizations (HMOs) require that conditions be identified and coded in terms of a predefined list of syndromes with pre-established measures of cost and risk. Calling for evidence-based medicine , HMOs are more likely to reimburse conditions that are defined as biological because diagnosis appears objective. 

Training of prescribes but also all staff in the elderly care, Evidence Based Medicine, Computerised Prescriber Order Entry, Educational Outreach, inappropriate medications, documentation of clinical benefits, risk medications, drug interactions, pharmacological alterations with age. 

Keywords Quality Benefits Risks Evidence based medicine... 

Evidence Based Medicine (EBM) is the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients (Sackett et al. 1996). It combines and integrates clinical knowledge of the patient, with best available external clinical evidence from systematic research. 

For more background, teaching and help on the practice of EBM the database at the Centre for Evidence Based Medicine (CEBM 2008) can be of help. 

Evidence based medicine combines and integrates clinical knowledge of the patient, with best available external clinical evidence from systematic research... 

CEBM (2008) Centre for Evidence Based Medicine. www.cebm.utoronto.ca/resources/cds.htm be. Cited 30 Dec 2008... 

Sackett DL, Rosenberg WM, Gray JA, Haynes RB, Richardson WS (1996) Evidence based medicine what it is and what it isn t. BMJ 312 71-72 Shepherd J, Blauw GJ, Murphy MB, Bollen EL, Buckley BM, Cobbe SM, Ford I (2002) Prospective study of pravastatin in the elderly at risk (PROSPER). Lancet 360 1623-1630... 

There are some external evidences from systematic research in the field. As for other Evidence based medicines principles, these evidences have to be used together with the knowledge of the individual patient characteristics. As described previously the physicians have difficulties in appraising the compliance behaviour of their patients. Therefore it is important to identify possible non-compliance based also on knowledge, attitudes and motivational aspects as described above. 

Greenhalgh T. How to Read a Paper The Basis of Evidence-based Medicine. London BMJ Publishing, 1997 93-5. 

The rapid accrual of biomedical information has led to considerable interest both in the notion of evidence-based medicine and also in the history of the use of quantitative evidence in medicine. Trohler has shown that the origins of a quantitative approach to medicine can be traced back to the eighteenth century in Britain and was a movement begun by physicians who believed that there was a need to move to an empirical approach to medicine and away from the systemic-pathophysiological approach of antiquity. 

Since its inception the NNT has been widely used not only to report the results of individual clinical trials, but more particularly in the evidence-based medicine world to report the results of systematic reviews, or meta-analyses (see Section 8.6). Its use by the evidence-based medicine fraternity has led to the NNT being incorporated into a number of treatment guidelines. Three of four recent clinical practice guidelines issued by the Australian and New Zealand College of Psychiatrists used the NNT in summarising results. Despite its popularity with clinicians, not all statisticians have been as supportive. ... 

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