Process and methods
8 Linking to other guidance
This chapter describes how guidelines link to other NICE guidance in the topic area and to guidance from other developers.
Related NICE guidelines and guidance on health technologies should be identified during scoping of a guideline (see chapter 2), or when checking if a guideline needs updating (see chapter 13). This includes identifying any related guidance or guidelines in development, as well as those that are published.
When a guideline topic covers guidance on health technologies that is published or in development, NICE staff with a quality assurance role work closely with NICE staff from the health technologies team to agree the approach to take.
A guideline committee cannot usually publish its own recommendations on health technologies covered by published or in development health technologies guidance. In rare cases, technology appraisal guidance will be updated in the guideline (see below).
When a technology appraisal is developed at the same time as a related NICE guideline, development should ideally be coordinated so that the appraisal recommendations are published in time for a link to be included in the consultation draft of the guideline. This is not always possible (for example, if the technology has not yet received a marketing authorisation). In this case, the guideline consultation draft should link to the appraisal consultation document or final appraisal determination. If guideline committee members wish to comment on the appraisal, they do this through the developer (see the technology appraisal process guide).
The guideline committee chair and the developer may attend relevant appraisal committee meetings as advisers, but do not take part in the formal decision-making.
If there is evidence that a technology appraisal needs updating, the NICE technology appraisals team follow the process in the technology appraisal process guide.
In rare cases, a technology appraisal is updated as part of guideline development, if the criteria in the policy on updating technology appraisals in clinical guidelines are met.
Early planning is essential to identify how the guideline developer will update technology appraisal guidance within a guideline. The developer should consider whether there are any data not in the public domain that are likely to be useful. If so, they should call for evidence from registered stakeholders, using the procedures described in section 5.5.
If there is significant new evidence or a change in costs since the technology appraisal guidance was published, the developer assesses cost effectiveness (performs an economic analysis) to determine whether a change in the recommendations is appropriate. In exceptional circumstances, it may not be clear that an economic analysis is needed until the evidence is reviewed and discussed by the committee. Nevertheless, the developer should start planning for any economic analysis at an early stage. The intended approach to cost-effectiveness (economic) analysis for technology appraisal updates should be included in the economic plan and discussed with the committee and a member of NICE staff with responsibility for quality assurance.
The approach should follow the principles described in chapter 7 and should be similar to that used in the technology appraisal. Any differences must be justified by changes in the evidence base or the decision context (for example, a broader range of comparators in the guideline).
The developer may sometimes consider that cost effectiveness can best be assessed by modifying or building on the architecture of an existing economic analysis from the technology appraisal. If so, this should be discussed with a member of NICE staff with responsibility for quality assurance during development of the economic plan.
A first assessment of a new medicine or a significant new indication for an existing medicine is usually carried out as a technology appraisal. However, in exceptional circumstances a first assessment can be carried out using the guideline development process, as long as this has been agreed by both the Department of Health and Social Care and the company.
When a new related technology appraisal is referred after the guideline has started development, and will be developed alongside the guideline, NICE's technology appraisals team informs the developer and NICE staff with responsibility for guideline quality assurance.
When related technology appraisal guidance is identified, the usual approach is for the guideline to make a recommendation to follow the technology appraisal recommendations with a link to where these appear in the NICE Pathway (everything NICE has said on the topic). If needed, a brief explanation can be included in the guideline recommendation, for example, if it covers the sequencing of treatments recommended in technology appraisals. Any explanation needs to be agreed with the technology appraisals team at NICE.
In rare cases, technology appraisal recommendations may be included in the guideline, for example, if this is essential for readability or there is a need to highlight specific recommendations.
Sometimes a guideline covers a medicine for which there is technology appraisal guidance, but for a different population or indication (condition). In these cases, the committee developing the guideline recommendation should assess evidence of effectiveness using methods described in this manual. The guideline recommendations may be different from the technology appraisal recommendations if there is evidence of differing safety or effectiveness for the population or indications covered by the guideline.
Related published or in development NICE guidelines should be identified by the developer at the scoping stage, or by the NICE surveillance team when checking if a guideline needs updating (see chapter 13). The scope should document which NICE guidelines are considered relevant for the guideline that is being developed. Any other related NICE guidelines that are highlighted during guideline development should be discussed, and a joint approach agreed with NICE staff with responsibility for quality assurance.
During scoping, identified related guidelines should be reviewed to determine whether the guideline in development will link to existing published recommendations (that is, the key issue(s) will be excluded from the scope of the guideline in development) or whether the guideline in development will consider similar review questions (that is, the key issues are included in the scope of the guideline in development).
When a guideline in development will link to recommendations in a published guideline, this will be specified in the scope.
When a similar review question is identified in a published NICE guideline, and the evidence review underpinning any recommendations is considered appropriate, the committee developing the guideline can choose to link to the recommendations in the published guideline or to draft new recommendations, based on the evidence review for the published guideline.
In these cases, the committee should discuss and document whether:
the review question in the guideline in development is similar enough to the question addressed in the published guideline
the evidence base underpinning any recommendations is unlikely to have changed significantly since the publication of the related guideline
the evidence review for the review question in the published guideline is relevant and appropriate to the question in the guideline in development.
If the committee agree that the evidence review is relevant for the guideline in development, they consider the recommendations based on the evidence review.
There are 3 options in these circumstances and these are described below.
If the committee are happy to accept the intent and exact wording of the recommendations, and understand that any future changes (for example, as part of an update) would also apply to their guideline, then the guideline will link to the recommendations in the published guideline. If needed, a recommendation can be added to the guideline explaining anything users will need to take into account when applying the recommendations from the published guideline (for example, if some parts of a recommendation do not apply to the population or setting covered by the new guideline). The committee's discussion and decision should be documented clearly in the guideline. This should include areas of agreement and difference with the committee for the published guideline (for example, in terms of key considerations – balance of benefits and harms or costs, and interpretation of the evidence).
Linking to other guidelines is preferred to copying recommendations into the guideline in development. In rare cases, recommendations may be copied into the guideline, for example, if this is essential for readability or there is a need to highlight specific recommendations.
If the committee considers that the intent and wording of the published recommendations are not appropriate for their guideline, or they are not prepared to agree that any updates to recommendations would also apply to their guideline, they may make new recommendations based on the existing evidence review. When evidence reviews from another guideline are used to develop new recommendations, the decision should be made clear in the methods section of the guideline, and their independent interpretation and discussion of the evidence should be documented in the discussion section. The evidence reviews from the published guideline (including review protocol, search strategy, evidence tables and full evidence profiles [if available]) should be included in the guideline. They then become part of the whole evidence base for the guideline, and are updated as needed in future updates of the guideline.
If the review question is not considered similar enough or the evidence review is not considered appropriate, the committee may request that a new evidence review is conducted. This should follow NICE's standard processes and methods, as described in this manual. The decision to conduct a new review should be agreed by NICE staff with responsibility for quality assurance, and documented in the methods section and the discussion section for the review question.
Interventional procedures (IP) guidance differs from other NICE guidance in that it addresses the safety and efficacy of interventions, and not their effectiveness or cost effectiveness. (For more details see the IP programme process guide.)
Any related published IP guidance should be identified during the scoping of a guideline or by the surveillance review. The approach depends on whether the recommendation in the IP guidance is for 'standard' (previously known as 'normal') or 'special' arrangements for clinical governance, consent and audit or research. Because guidelines focus on placing established treatments in the care pathway, they will generally only include IP guidance that recommends 'standard' arrangements.
If IP guidance on a procedure relevant to a guideline starts development during development of the guideline, the IP programme will send the finalised scope(s) for the procedure(s) to NICE staff with responsibility for quality assurance of the guideline.
If the scoping group for a guideline decides that IP guidance for which 'standard' arrangements (previously known as normal arrangements) are recommended is relevant to the guideline but does not justify a review question, the guideline simply links to the IP guidance in the NICE Pathway. The developer does not search for new evidence on procedures that are not incorporated into a review question. However, if in the course of their search for evidence for the guideline the developer finds new relevant evidence on that procedure, they inform the IP team at NICE.
If the scoping group for a new guideline considers that IP guidance with 'standard' arrangements is likely to justify a review question, this is highlighted in the scope for the guideline. For example, comparisons of clinical and cost effectiveness could be included if there is IP guidance covering several procedures for the same condition. The IP team is contacted by NICE staff with responsibility for guideline quality assurance during scoping to seek their input on the proposed approach.
If a guideline is being updated and the surveillance review identifies that IP guidance with 'standard' arrangements is likely to justify a review question in the updated guideline, this is highlighted in the surveillance report.
When a review question in a guideline relates to IP guidance, the IP guidance remains active unless the IP team and NICE staff with responsibility for guideline quality assurance have identified reasons why not. This is because the IP guidance relates to the efficacy and safety of the procedure, and so the guideline and the IP guidance address different questions. Therefore IP guidance remains current even if the recommendations are supplemented by a guideline recommendation on the effectiveness of a procedure for 1 or more indications. IP guidance may also contain more detailed information that may be of value to practitioners and people considering having the procedure. Importantly, the IP guidance may also specify conditions for use of the procedure; for example, that the surgeon should have training, or that the procedure should be carried out within the context of a multidisciplinary team. The guideline will link to the IP guidance in the NICE Pathway, and the NICE webpage for the IP guidance will include a link to the guideline.
If NICE staff with responsibility for guideline quality assurance and the IP team agree that a different approach is needed, they present a paper to NICE's Guidance Executive. Decisions to take other approaches are made on a case-by-case basis. Examples include:
Appraisal of the evidence indicates that a procedure with IP guidance is not effective, and the guideline recommends that it should not be used.
There is considerable uncertainty about the clinical or cost effectiveness of a procedure.
The guideline committee makes a 'research only' recommendation for a procedure with published IP recommendations for 'standard' arrangements.
If the guideline committee considers that a procedure with recommendations for 'special' arrangements has become part of NHS practice and falls into the area of a review question, the IP team is notified for potential review of the IP guidance. If the guidance is reviewed and the procedure's status is changed to 'standard' arrangements, the developer considers the procedure's effectiveness and cost effectiveness. If the procedure retains its 'special' arrangements status, the guideline should link to the IP guidance in the NICE Pathway.
Sometimes IP guidance recommends that a procedure should only be carried out in research, or that it should not be used. A recommendation not to use a procedure is made if there is no evidence of efficacy and/or safety, or evidence of a lack of efficacy and/or safety. A 'research only' recommendation is made if the evidence shows that there are important uncertainties. The evidence base for procedures with recommendations for 'research only' or 'do not use' usually reflects the fact that they are not established procedures. As such, they would not normally form part of a review question in a guideline.
When a newly notified procedure has been scoped and it has been agreed that it will be assessed by the IP team, the IP team informs the developer and NICE staff with responsibility for guideline quality assurance that the notified procedure is relevant to the guideline. The guideline can link to the IP guidance when it is published.
Sometimes relevant guidelines published by organisations other than NICE are identified in the search for evidence and considered appropriate for inclusion in the evidence base. Guidelines produced by organisations accredited by NICE are not subject to further appraisal of the guideline development process because this has already been assessed by NICE. However, the evidence reviews in the guideline will still need to be critically appraised (using checklists in appendix H) to ensure that the quality of the evidence is appropriate for deriving NICE recommendations.
Published guidelines produced by organisations not accredited by NICE are assessed for quality using the AGREE II instrument or the AGREE global rating scale instrument. There is no cut‑off point for accepting or rejecting a guideline, and each committee needs to set its own parameters. These should be documented in the methods of the guideline, and a summary of the assessment included in the evidence review. The full results of the assessment should be presented with the guideline.
Reviews of evidence from other guidelines that cover review questions being addressed by the committee may be considered as evidence if they are:
If using evidence from published guidelines, the committee should create its own evidence summaries or statements (see section 6.4). Evidence tables from guidelines published by other organisations should be referenced with a direct link to the source website or a full reference of the published document. The committee should formulate its own recommendations, taking into consideration the whole body of evidence.
Recommendations from guidelines published by another organisation should not be quoted or linked to, unless the organisation's process has been accredited by NICE and the evidence reviews have been critically appraised to verify quality.
Brouwers MC, Kho ME, Browman GP et al. (2010) AGREE II: advancing guideline development, reporting and evaluation in health care. Canadian Medical Association Journal 182: E839–42