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Denominator:
Θα κάνετε τον κόπο να ανεβάσετε ένα pdf από μία μελέτη που θεωρείτε ότι έχει grade πάνω από Ε;

Rose:
Επιπρόσθετες πληροφορίες: Evidence-based Complementary and Alternative Medicine

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Evidence-based Complementary and Alternative Medicine

Evidence-based Complementary and Alternative Medicine (eCAM) is an international, peer-reviewed journal that seeks to understand the sources and to encourage rigorous research in this new, yet ancient world of complementary and alternative medicine.
Publisher: Oxford University Press

26 issues are available electronically
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The Journal of Alternative and Complementary Medicine

Teaching Evidence-Based Complementary and Alternative Medicine: 1. A Learning Structure for Clinical Decision Changes
To cite this article:
Edward J. Mills, Taras Hollyer, Gordon Guyatt, Cory P. Ross, Ron Saranchuk, and Kumanan Wilson. The Journal of Alternative and Complementary Medicine. April 2002, 8(2): 207-214. doi:10.1089/107555302317371514.

Published in Volume: 8 Issue 2: July 5, 2004
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______________________________________________________________________

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Evidence Based Complementary and Alternative Medicine

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Mission

eCAM is an international rigorously peer-reviewed journal devoted to the advancement of science in the field of basic research, clinical studies, methodology or scientific theory. It will include the following areas in Biomedical Sciences: Phytotherapy (Herbal Medicine); Ayurvedic-Medicine, Traditional Chinese Medicine (TCM); KAMPO-Medicine, TAIM (Traditional Arabic and Islamic Medicine); Homeopathy; Acupuncture/Acupressure, Hydrotherapy (Balneology) and Relevant Animal Molecules (RAMS) and Neuroimmune Mechanisms (NIMS).

Only papers that are of highest scientific quality concisely written and comply with the Guidelines for Authors will be accepted. Manuscripts involving volunteers and patients must include a statement that the trial protocol has been approved by an ethical committee and thus meets the standards of the Declaration of Helsinki. The journal welcomes studies on herbal and animal products, identification of the active ingredients, their mechanisms of action, combinatorial studies, and quality control and quality assurance. These will follow the ICH (International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for human use) guidelines, preclinical evaluations encompassing, animal models, in vitro studies, toxicity and safety evaluations, dosimetry, efficacy assessments, clinical investigations. These will include retrospective and prospective studies with matched controls, placebos, randomized trial, comparisons with existing protocols and pharmaceuticals for treatment, and different phases of the clinical trials. Contributions will be reviewed in one of the following categories: Original Articles, Reviews, Editorials, Commentaries, and a Lecture Series.[/spoiler]

Denominator:
Ποια μελετη επιλεξατε με grade ανω του Ε;

Loumakis:
Τα ερωτήματα πολλά, ο διαθέσιμος χρόνος λίγος, παρ' όλα αυτά ας αρχίσουμε σιγα-σιγα να απαντάμε, καλλιεργώντας ένα γόνιμο διάλογο αντίθετων απόψεων.

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Ανακεφαλαιώνω:
1) Υπάρχει evidence-based εναλλακτική ιατρική σε επίπεδο μεγαλύτερο του Ε;
2) Γιατί δεν ασφαλίζεται κανείς εναλλακτικός από τις ασφαλιστικές εταιρείες για αστική ευθύνη αφού υπάρχει τόσο μεγάλη διεθνής εμπειρία;

--- Τέλος παράθεσης ---

   Ερώτημα 1: Σε μεμονωμένες έρευνες ναί, εάν δεις το θέμα συνολικά, δηλαδη πάρεις το "αλγεβρικό άθροισμα" όλων των ερευνών με θετική και μη-θετική απάντηση στο ερώτημα "είναι η Ομοιοπαθητική αποτελεσματική;" τότε ίσως όχι [αν και το προηγούμενο κατεβατό ερευνών από τη rose μπορεί να με κανει να αναθεωρήσω/ τι ξεφτίλα κι αυτή, ομοιοπαθητικός γιατρός ο ίδιος να πληροφορούμαι από άλλους, μη γιατρούς, δεδομένα ενισχυτικά της μεθόδου που χρησιμοποιώ  :D ]. Τονίζω το "μη-θετική", διότι η μη-θετική απάντηση δεν ταυτίζεται, ως γνωστόν, με την αρνητική, πραγμα το οποίο οι πολέμιοι της Ομοιοπαθητικής αποσιωπούν. Το να πώ "η έρευνα μου δεν απέδειξε την αποτελεσματικότητα της Ομοιοπαθητικης αγωγής" δεν ταυτίζεται νοηματικά με τη φράση "η έρευνα μου απέδειξε την αναποτελεσματικότητα της Ομοιοπαθητικης αγωγής". Στην πρώτη περίπτωση σημαίνει ότι η έρευνα μου δεν έδειξε διαφορά μεταξύ Ομοιοπαθητικης αγωγης και placebo σε επίπεδο στατιστικά σημαντικό, όχι απαραίτητα λόγω αναποτελεσματικότητας  της Ομοιοπαθητικης αγωγης, αλλά λόγω ανεπαρκούς ισχύος της συγκεκριμένης έρευνας ως επιστημονικού εργαλείου για να αναδείξει τη θεραπευτική αποτελεσματικότητα της (π.χ. μικρός αριθμός ασθενών, λανθασμένη μεθοδολογία κλπ.). Παρ' όλα αυτά οι πολέμιοι της Ομοιοπαθητικής συγχέουν (σκόπιμα; ) τις δύο εκφράσεις, εκλαμβάνουν τη "μη-θετικότητα" ως αρνητικότητα και προβάλλουν στα ΜΜΕ και στον απλό κόσμο με τον ίδιο τρόπο τα αποτελέσματα των ερευνών (αν δεν μπορεί να καταλάβει τη διαφορά ένας γιατρός, πολύ λιγότερο ή μάλλον καθόλου δεν θα την καταλάβει ο δημοσιογράφος και απλός πολίτης).
   Μίλησα παραπάνω για λανθασμένη μεθοδολογία. Κάτι που πολλοί αγνοούν είναι ότι πολλες "ομοιοπαθητικες" ερευνες γίνονται από κλασικούς γιατρούς άσχετους με τους κανόνες της Ομοιοπαθητικής. Παίρνουν μια ομαδα ασθενων, τους δίνουν το ίδιο ομοιοπαθητικό φάρμακο, μία άλλη ομάδα σύγκρισης και τους δίνουν placebo και μετράνε τη διαφορά. π.χ. ειχαν πάρει μια ομάδα ασθενών με ρευματοειδή αρθρίτιδα, εδωσαν σε όλους το ομοιοπαθητικό φάρμακο Rhus-Tox (συχνα χρησιμοποιούμενο στη Ρ.Α. από την Ομοιοπαθητική), στην ανάλυση βγήκε (φυσικό και αναμενόμενο από την πλευρά της Ομοιοπαθητικής) ότι δεν υπήρχε διαφορα από το placebo και θριαμβολογούσαν. Αυτό είναι εξωφρενικό, διότι στην Ομοιοπαθητική εξατομικεύεις τη θεραπεία με βάση τα ιδιαίτερα χαρακτηριστικά του ασθενούς, όπως προκύπτουν από το ομοιοπαθητικό ιστορικό. Δέκα ασθενείς με την ίδια ακριβώς πάθηση ενδέχεται να πάρουν δέκα διαφορετικες (ομοιοπαθητικές) θεραπείες, αναλογα με τα ατομικά χαρακτηριστικά τους. Αρα, εάν θέλουμε να γίνουν μεθοδολογικά σωστες έρευνες πάνω στο θέμα, πρεπει να συνεργασθούν γιατροί της κλασικης και της ομοιοπαθητικής ιατρικης, ώστε να βρεθεί ο κοινός τόπος των κανόνων των δύο πλευρών και με βαση αυτόν τον κοινό τόπο να γίνουν οι έρευνες. Αυτό είναι κατι που η Ομοιοπαθητική επιθυμεί διακαώς και δέχεται την πρόκληση, αλλά που ο σνομπισμός των εκπροσώπων της κλασικης ιατρικης απέναντι της δεν αφήνει να γίνει (πρώτο εμπόδιο στην καθιέρωση της Ομοιοπαθητικής, κρατήστε το, γιατι υπαρχουν κι άλλα).
   Είπα οτι για να ανέβει επίπεδο στην κλίμακα αξιολόγησης της evidence-based medicine η ομοιοπαθητική ιατρική, χρειάζονται έρευνες με μεγάλο αριθμό ασθενών. (Συνειρμικά αυτή η αξιολόγηση μου φερνει στο νού τις αξιολογήσεις των εθνικων οικονομιών από οίκους τύπου Standard's and Poor's, Moody's κλπ., αξιολογήσεις συχνα όχι αντικειμενικες, αλλά κατευθυνόμενες από υποκρυπτόμενα συμφέροντα.) Πώς να γίνουν όμως τέτοιες έρευνες όταν τα απαιτούμενα κονδύλια είναι τεράστια και δεν είναι διαθέσιμα από ομοιοπαθητικής πλευράς; Οι περισσότερες ερευνες σήμερα, ως πασίγνωστον, χρηματοδοτούνται από φαρμακευτικες εταιρείες, οι οποίες βέβαια δεν τρελλάθηκαν να επιχορηγήσουν μια θεραπευτική μέθοδο, που αν επικρατήσει θα φέρει "τα πάνω κάτω" στον χώρο της αγοράς του φαρμάκου. Θα ήταν καθαρή αυτοκτονία εκ μέρους των. (Δεύτερο εμπόδιο στην καθιέρωση ή αναβάθμιση της Ομοιοπαθητικής)

  Διακόπτω εδώ, χωρις να έχω ολοκληρώσει, γιατί η κούραση από τις δραστηριότητες της ημέρας δεν με αφήνει να συνεχίσω. Θα επανέλθω στο θέμα, ελπίζω σύντομα.

Rose:
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The GRADE System for Rating Clinical Guidelines

Citation: Kavanagh BP (2009) The GRADE System for Rating Clinical Guidelines. PLoS Med 6(9): e1000094. doi:10.1371/journal.pmed.1000094

Introduction

Professional medical groups commonly issue clinical practice guidelines. Such guidelines are traditionally the result of consensus conferences or expert panels and represent attempts to synthesize—from the best available evidence and expertise—practical guidance on the best possible care. Beyond issuing a guideline, many organizations have felt the need to provide a grading of each guideline's quality, thereby conveying to the reader a sense of the confidence that might be placed in it. This article addresses only the grading of guidelines, not their use or development.

The idea that evidence in the medical literature should be graded was initially proposed in publications from McMaster University [1]–[3], with the idea of categorizing individual studies into grades of reliability ranging from randomized controlled trials (most reliable) to case reports with expert opinion (least reliable). Grading of guidelines followed, but this has been besieged with problems. To give one example, a guideline by Ferraris and colleagues gave the use of aprotonin during high-risk cardiac surgery a “high-grade” recommendation [4], but this intervention was subsequently shown to increase mortality [5].

The pursuit of better approaches to grading guidelines has resulted in GRADE (Grades of Recommendation Assessment, Development and Evaluation), introduced in 2004 [6]. GRADE has been adopted “unchanged or with only minor modifications” by national and international professional medical societies, health-related branches of government, health care regulatory bodies, and UpToDate, an on-line medical resource that is accessed by trainees and physicians in most US academic medical centers (Box 1) [7],[8].

[...]

Is GRADE Internally Consistent?

Inter-rater agreement of GRADE.
In 2005, the GRADE working group—all experts who themselves developed the GRADE system—published a pilot study of the system [16]. The study found that the kappa value (i.e., the inter-rater agreement beyond chance) for 12 judgments about the quality of evidence was very low (mean κ = 0.27; κ<0 for four judgments). The authors stated that “with discussion” they were able to considerably improve their system, but provided no supportive data. Furthermore, the presentation of GRADE that had been published a year earlier in 2004 contains neither assessment of reliability, agreement, nor proof of usefulness [6].

[...]

GRADE experts versus content experts.

Comparing expert opinion on sepsis with the result of the GRADE process further suggests that GRADE lacks internal consistency.

First, glucose control in the critically ill is a complex issue [17]. Recent clinical data suggest no benefit to widespread application of “tight” glucose control (i.e., intensive insulin therapy) in most intensive care unit (ICU) patients [18]–[21]. Brunkhorst and colleagues state that intensive insulin therapy has “no measurable consistent benefit in critically ill patients in a medical ICU regardless of whether the patients have severe sepsis and that such therapy increases the risk of hypoglycemic episodes” [18]. Yet the senior author of that report [18], Konrad Reinhart, is a coauthor of the SSC guidelines that gave a grade 1 ranking (strong recommendation) for “moderate” glucose control and a grade 2 endorsement (a suggestion) for “tight” glucose control [11]. No evidence exists for moderate glucose control in this context, whereas the value of tight control was supported by one single-centre randomized controlled trial (RCT) [22] and opposed by four others [18],[20]–[21],[23]. Since the 2008 SSC forum [11], the largest multicentre study, the NICE-Sugar trial, reported that tight glucose control increased ICU mortality by 2.6% (OR 1.14) [24].

Second, the SSC strongly recommends (i.e., grade 1) specific resuscitation targets (blood pressure, urine output, central venous pressure, central venous oxygenation) [11], on the basis of the protocol of a commonly cited single-centre study [25]. In a different forum, the SSC states: “It is impossible to determine from the study which particular facet of the protocol was beneficial for the patients, so the protocol as a whole must be recommended” [26]. But there is considerable debate about the usefulness of this protocol—two ongoing studies are examining if the protocol is effective [27]–[28]. One of these studies is led by Derek Angus, an author of the SSC guidelines [11]. Thus, I see an inconsistency in a grading system where the most authoritative expert in the SSC panel is investigating if the protocol is useful versus the aggregate panel decision concluding a strong recommendation that it should be used [11].

Is GRADE Inherently Logical?

Strength of recommendation and quality of evidence.
GRADE provides an expression of the strength of the recommendation and also provides a rating on the quality of the evidence upon which the recommendation is based. In terms of strength, GRADE considers evidence to be “strong” or “weak.” The GRADE group considers strength to reflect “the degree of confidence that the desirable effects of adherence to a recommendation outweigh the undesirable effects” [7]. This component makes sense, but less so when the strength of the recommendation is dissociated from its foundation (i.e., the quality of the evidence that underpins the recommendation). The group emphasizes the importance of making this dissociation: “Separating the judgments regarding the quality of evidence from judgments about the strength of recommendations is a critical and defining feature of this new grading system” [7]. One can envision having “high-quality” knowledge that points to a small effect (high quality, low strength). The converse, low quality knowledge that yields a high-strength recommendation seems implausible, other than perhaps the avoidance of substances such as potent toxins.

Combining incommensurate elements.
Another problem is the “leveling” process proposed to determine the quality of the evidence. GRADE ranks the quality of evidence on the basis of the type of study, “quality” issues (e.g., blinding, follow-up, sparseness of data), consistency, directness (generalizability), and effect size. The graders are instructed to raise or lower the level of quality and trade off, for example, the presence of sparse data against demonstration of a dose-response effect [6]; of course these are fundamentally different and can therefore be neither added nor subtracted.

GRADE Has Not Been Validated

The basis for the GRADE system is articulated in several publications [6]–[7],[9],[16],[29]–[31], but none contains supportive data, proof, or logical argument for the system. Rather, there is extensive reference to other papers written largely by the same group but with no data (except a very low kappa value for inter-observer agreement) [16]. Thus, there is no literature-based proof of the validity of the GRADE system; indeed using approaches for appraising evidence proposed by the Evidence-Based Medicine Working Group [32], I would conclude that there is little basis for GRADE.

The GRADE documents suggested that strong recommendations should require little debate and would be implemented in most circumstances [7],[29]. At first glance, this may seem reasonable but there could be unanticipated consequences, such as stifling debate about many important topics, with the result that there is less thought and less research on that topic. High-level recommendations using other grading systems strongly advocated use of beta-blockade (class I, IIa) [33]–[34] and aprotinin (class 1a) [4] in specific surgical populations. But assuming that the subsequent RCTs were appropriately conducted [5],[35], the original high-level recommendations were clearly misguided [4],[33]–[34]. A major concern about any grading system is that if enshrined, potentially life-saving prospective studies might not be permitted by research ethics boards on the basis that because a guideline has been assigned a “confident” grading, equipoise does not exist.

Popularity and Uptake

The GRADE system has been adopted as is, or with minor modifications, by a large number of professional, statutory, and medically related governance organizations (Box 1). It is hard to understand why so many organizations, many of them leading regulatory or professional groups, would adopt a system that has no proof of effectiveness and has demonstrated inconsistency [16]. There are several possible reasons for its popularity: (1) a perceived need to regulate and reduce “unnecessary” and potentially harmful variation in health care [36]; (2) GRADE uses attractive language (such as “clarity,” “consistency,” “helpfulness,” and “rigor”) [6],[37]–[38]; (3) the attraction of the promise of clinical excellence being obtainable through such a system; (4) influential bodies may adopt GRADE in order not to be left behind what some view as a “state-of-the-art” scientific advance.

GRADE: Potential for Bias

The SSC describes in detail how members of the GRADE group interacted with the sepsis experts and influenced the grading decisions [11]. But it is not clear to me why the GRADE group needed to be involved at all in the grading decisions given that all the SSC members are experts. Given also that the GRADE criteria are conveyed as “explicit and clear” [6], there should be little need for intensive methodological consultation from the GRADE group when experts produce guidelines. While grading experts might be helpful to explain technical elements of grading, the above scenario raises the possibility of the grading process shaping the medical message.

GRADE: Implications for Practice and Policy

The GRADE group writes that for clinicians, strong recommendations should be seen as a quality criterion or performance indicator, and for policy makers, be adopted as policy [7]. There are similar efforts underway to synthesize studies and implement practice guidelines in several countries, including the UK and the US [39]–[41]. But knowing which studies and guidelines are best (or are valid) [42] is not straightforward—high-grade recommendations (such as [4],[33]–[34]) have been later proved wrong [5],[35].

It is not clear that the opinion of a conscientious, judicious, well-educated, and experienced clinician would necessarily be inferior to a systemized opinion, such as GRADE, especially if GRADE is not valid. Conferring a “strong” rating upon a guideline will constitute a major deterrent to a clinician considering an alternative clinical route, particularly if GRADE recommendations were to be adopted as a policy by regulatory bodies [7]. Indeed warnings have been issued about proposals to convert guidelines into law [43]–[44].

What Should Replace GRADE?

A key question that arises when a system is questioned is: what is the alternative? There is a very good alternative to using the GRADE system to rate clinical guidelines: clinicians and organizations should use published guidelines while considering the clinical context, the credentials, and any conflicts of interest among the authors, as well as the expertise, experience, and education of the practitioner. If in the future a guideline grading system is shown to improve outcome and is without harm, it could usefully be incorporated into clinical practice.

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