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MSc MRPharmS MBA CPP
RPSiS representative on SIGN Council
Lead Pharmacist for Clinical Governance
North Glasgow University Hospitals NHS Division
The Scottish Intercollegiate Guidelines Network (SIGN) was formed in 1993. The founding chairman, Professor James Petrie, successfully argued the case for a professionally led organisation representing the medical Royal Colleges, specialist associations of healthcare professionals and relevant educational bodies to develop clinical guidelines. SIGN was therefore established under the auspices of the Academy of Royal Colleges and medical faculties in Scotland, with funding from the Scottish Office provided through the Clinical Resource and Audit Group (CRAG).
In 2003, in common with other key clinical governance organisations, SIGN became part of the National Health Service (NHS), with funding channelled through NHS Quality Improvement Scotland (NHSQIS). However, selection of topics, methodology used and editorial independence of the guidelines remained under the control of the SIGN council.
The aim of SIGN is to improve the quality of healthcare for patients in Scotland by reducing variations in practice and outcome, through the development and dissemination of national clinical guidelines containing recommendations for effective practice based on current evidence. SIGN guidelines are developed using a rigorous and systematic methodology to ensure the development of nonbiased, evidence-based clinical guidelines that will ultimately improve patient care. It is this systematic methodology for which SIGN is internationally renowned today.
Based within the Royal College of Physicians in Edinburgh, the executive SIGN staff comprises a total of 17 people. The executive staff report to the SIGN council, itself consisting of representatives of all medical specialties, nursing, pharmacy, dentistry, professions allied to medicine, patients, health
service managers, social services and researchers.
Usefulness of evidence-based guidelines in practice
Clinical evidence-based guidelines provide an easily accessible summary of current evidence and recommended practice based on the evidence. They allow clinicians direct access to the best practice in other areas within the NHS. Most importantly, SIGN guidelines provide important information for patients and carers.
Topics are selected after wide national consultation, based on proposals received from a variety of individuals.(1) A core of the selected topics are then presented to the Guideline Programme Advisory Group (GPAG), the members of which systematically “score” the guidelines for presentation to the SIGN council using specific criteria. Those with the highest scores go forward for review by the SIGN council, which then decides which topics will be accepted in the programme for the following year, subject to approval by NHSQIS. The guideline development programme for 2004–2005 includes autistic spectrum disorders, cervical cancer, control of cancer pain review, antibiotic prophylaxis review, hepatitis C, gastrointestinal blood loss and meningococcal disease.
Once a topic is agreed as part of the work programme, the Guideline Development Group (GDG) is formed. The GDG is “managed” by a programme manager from the SIGN executive but is chaired by a specialist in the clinical field. Consultation around membership of the GDG is extensive, to ensure that all appropriate healthcare professionals are represented. The multidisciplinary GDG represents a cross-sector of the relevant healthcare professionals from across Scotland. It is important to ensure that a variety of geographical areas are represented, and that their expertise is utilised effectively.
During development, the GDG formulates key questions from the overall topic. These questions form the basis of a literature search, which is undertaken by the SIGN information team using a variety of databases, including the Cochrane Library, Medline and Embase.
The evidence is scored depending on the weight of clinical evidence, not clinical importance. Subgroups of the GDG review the literature associated with their key questions from the guideline topic.
Scoring the evidence
Evidence is linked explicitly to the supporting evidence and graded according to the strength of that evidence. Initially, the system for the grading of evidence was that of the US Agency for Healthcare Research and Quality. Following a review, a new system was implemented in 2001.(2) Randomised controlled trials (RCTs) give the best level of unbiased evidence, but cognisance needs to be taken of the quality of other study designs and of the best available evidence. This new grading system seeks to take into account the methodological quality, quantity, consistency and applicability of the evidence base.
Synthesising the evidence
The direction of the evidence is then considered. Evidence originating from small trials requires an extra body of evidence to show consistency of evidence of effect, whereas a well-designed large RCT may stand alone in support of a recommendation. Healthcare professionals need to have faith in the guidelines they follow.(3,4) To make sure that this is the case, the GDG considers the quality, quantity, consistency, applicability, generalisability and clinical impact of what they recommend. The group is required to present how they link the evidence to the recommendation in a clear way. By doing so, any bias is reduced.
National consultative meetings
Each GDG hosts a national consultative meeting, approximately one year after commencing development of the guideline. This meeting:
Patients participate in the development of the guideline and are generally present at the national meeting. Following the national meeting, the guideline is sent out for wide peer-review, before finally being edited by the SIGN editorial board.
The quality of the guideline developed depends on the quality assurance mechanisms applied throughout guideline development. SIGN ensures the quality of guidelines by adopting a structured, systematic and methodological approach. This methodology meets most of the criteria of the Appraisal of Guidelines Research and Evaluation (AGREE), an internationally recognised tool for the evaluation of guidelines. By using such indicators, guideline development is being harmonised internationally, thereby reducing duplication of effort.
SIGN is not responsible for the implementation of the guidelines. This task is generally undertaken at a local level, via clinical governance committees.
Local implementation of guidelines can be a challenge, because of the potential resources required. However, even partial adoption of the recommendations can ensure better treatment outcomes for patients.
Patients play an important role in the development of SIGN guidelines, and a section at the end of each guideline seeks to identify the key issues of concern to patients.
Since 1993, SIGN has published 77 guidelines covering a wide variety of topics, ranging from “The management of diabetes”(5) to “The management of harmful drinking”.(6)
Many guidelines are related to the national priority areas of cancer, mental health, child health and cardiovascular diseases. The strategic aim is to improve health and tackle inequalities of healthcare.
Closing the loop: external audit of practice
Part of the role of NHSQIS is to undertake external audit of organisations within the NHS. SIGN guidelines provide the evidence base for many of the standards set by this independent body.
The rigorous methodology applied in the development of SIGN guidelines ensures a low level of bias and, ultimately, leads to the development of an evidence-based clinical guideline that will improve patient care within the NHS in Scotland.
The pharmacist has a key role to play at all stages in the process, whether it is being a member of a GDG, chairing the GDG or presenting at a national meeting.
It is therefore essential that, during consultation, GDG membership pharmacists are viewed as key members of the multidisciplinary team, as they have a valuable part to play in the improvement of patient care.
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