Changes

October 2024 — reviewed. A literature search was conducted in September 2024 to identify evidence-based guidelines, UK policy, systematic reviews, and key randomized controlled trials published since the last revision of this topic. The recommended dose of sustained-release nifedipine for drug prophylaxis has been amended, in line with the consensus best practice pathway of the UK Scleroderma Study Group (2015). The prescribing information section has been updated and expanded, in line with current CKS style. No major changes to recommendations have been made.

Update

Goals

To support primary healthcare professionals to:

• Be aware when to suspect Raynaud's phenomenon and make a working diagnosis.
• Be able to differentiate between suspected primary and secondary Raynaud's phenomenon.
• Offer management in primary care, when appropriate.
• Offer information on sources of information and support.
• Arrange referral to secondary care for further assessment and management, if appropriate.

Outcome measures

Audit criteria

QOF indicators

QIPP - Options for local implementation

NICE quality standards

What is it?

• Raynaud's phenomenon describes cold- or stress-induced episodic vasospasm of the arteries or arterioles in the extremities (usually the digits) which usually leads to transient, reversible skin colour change, typically [Belch, 2017]:
  • Blanching (due to vasospasm and vasoconstriction) which is necessary to make the diagnosis, which may be followed by:
  • Cyanosis (due to deoxygenation of static venous blood), and/or
  • Rubor or erythema (due to reperfusion and reactive hyperaemia). This may be associated with significant pain.
• Raynaud’s phenomenon can be classified as [Belch, 2017] [Haque, 2020] [Curtiss, 2024a]:
  • Primary (or idiopathic) — occurs in 80–90% of cases with no associated or underlying condition (previously known as 'Raynaud disease').
  • Secondary — occurs in 10–20% of cases due to an associated cause or underlying condition (previously known as 'Raynaud syndrome'). See the section on Causes and associated conditions for more information.

What are the causes and associated conditions?

The pathogenesis of Raynaud's phenomenon involves a complex interplay between genetic, neural, vascular, and intravascular factors that regulate peripheral blood flow [Haque, 2020] [Choi, 2021].

• Primary Raynaud’s phenomenon occurs in the absence of an underlying disease or cause [Belch, 2017] [Curtiss, 2024a].
  • The pathogenesis is not fully understood but abnormalities in neural control of vascular tone are likely to be involved, leading to an exaggerated sympathetic vasoconstrictive response of the small arteriovenous anastomoses to cold exposure. These structures play a key role in maintaining stable core body temperature by thermoregulation [Belch, 2017; Shapiro, 2017].
  • About 30% of people with primary Raynaud's phenomenon report having an affected family member [Curtiss, 2024a].
• Secondary Raynaud’s phenomenon is associated with an underlying condition, environmental exposure, or medication which may precipitate or exacerbate symptoms, such as:
  • Connective tissue disease — for example systemic sclerosis (Raynaud's phenomenon occurs in about 90% of people), mixed connective tissue disease (85%), systemic lupus erythematosus (10–45%), Sjögren’s syndrome (occurs in 33%, often with primary biliary cirrhosis), rheumatoid arthritis (10%), and dermatomyositis/polymyositis (20%). See the CKS topics on Cirrhosis and Rheumatoid arthritis for more information [Belch, 2017; Herrick, 2017].
    • Raynaud’s phenomenon is the most common presenting feature of systemic sclerosis and can precede a diagnosis of connective tissue disease by several years if a person has the 'limited cutaneous' sub-type of systemic sclerosis [Belch, 2017].
  • Obstructive vascular disease/atherosclerotic disease (especially in older age groups); arterial embolization; Buerger's disease (thromboangiitis obliterans) [Belch, 2017; Herrick, 2020; Casanegra, 2021; Curtiss, 2024a]. See the CKS topics on Peripheral arterial disease and Superficial vein thrombosis (superficial thrombophlebitis) for more information.
  • Extrinsic vascular compression — for example due to thoracic outlet syndrome or carpal tunnel syndrome [Belch, 2017; Herrick, 2020]. See the CKS topic on Carpal tunnel syndrome for more information.
  • Haematological conditions — including cryoglobulinaemia; polycythaemia vera; protein C, protein S, or antithrombin III deficiency; Factor V Leiden; and paraproteinaemia [Herrick, 2020; Curtiss, 2024a]. See the CKS topic on Multiple myeloma for more information.
  • Endocrine conditions — such as hypothyroidism, phaeochromocytoma, and carcinoid syndrome [Belch, 2017]. See the CKS topic on Hypothyroidism for more information.
  • Drugs — including non-selective beta-blockers, ergot derivatives, bromocriptine, oestrogens, ephedrine, amphetamines, caffeine, cocaine, cannabis, some cytotoxic drugs, and interferons [Belch, 2017; Herrick, 2020; Curtiss, 2024a].
  • Occupational — hand-arm vibration syndrome and hand-hammer syndrome (the risk relating to the degree and duration of vibration exposure); or environmental chemicals such as vinyl chloride monomer, silica, and solvents [Belch, 2017; Herrick, 2020; Curtiss, 2024b].
  • Low body mass index (BMI) — loss of thermoregulation function and increased cold sensitivity [Belch, 2017; Nawaz, 2022].
  • Other — 'systemic vasospasm' disorders such as migraine, Prinzmetal's angina, and irritable bowel syndrome may be associated with primary Raynaud's phenomenon [Belch, 2017; Casanegra, 2021]. See the CKS topics on Angina, Irritable bowel syndrome, and Migraine for more information.

How common is it?

• Raynaud’s phenomenon is relatively common, but prevalence rates vary with geographical region and climate [Choi, 2021].
  • The European Society for Vascular Medicine (ESVM) expert consensus document cites evidence in the literature that [Belch, 2017]:
    • The population prevalence varies widely (from 3–21%) depending on the definition used, geographical location, and local climate. Prevalence is higher in colder regions.
    • Primary Raynaud’s phenomenon is nine times more common in women than men.
    • Primary Raynaud's phenomenon has an overall prevalence of 10% in the general population.
    • Primary Raynaud's phenomenon typically presents in teenagers and young adults in the second or third decade.
    • Over 90% of people with systemic sclerosis have secondary Raynaud’s phenomenon.
    • There is a prevalence of occupational Raynaud's phenomenon in 50% of all workers using vibrating tools for any significant period of time.
  • Expert opinion in a review article states that most population-based surveys estimate the prevalence of Raynaud's phenomenon to be 3–5% in the general population [Wigley, 2016].
  • A UK survey of 720 children aged 12–15 years using a validated self-completed questionnaire found [Jones, 2003]:
    • 18% of girls and 12% of boys reported symptoms of Raynaud's phenomenon.
    • The prevalence increased with age.
  • A systematic review and meta-analysis of 33 observational studies of primary Raynaud's phenomenon obtained from 5 electronic databases (n = 33,733) reported [Garner, 2015]:
    • A pooled prevalence of 4.85% in the general population.
    • A pooled annual incidence of 0.25% in the general population.
    • Identified risk factors included female sex (odds ratio [OR] 1.65), positive family history (OR 16.6), smoking (OR 1.27), manual occupation (OR 2.66), cardiovascular disease (OR 1.69), and migraine (OR 4.02).
    • There was variation in the definition of primary Raynaud's phenomenon between the studies.

What is the prognosis?

• Primary Raynaud’s phenomenon is typically associated with mild symptoms and does not progress or lead to irreversible tissue injury [Belch, 2017] [Casanegra, 2021].
  • A large community-based prospective cohort study (n = 717 women and 641 men) over a 7-year period found [Suter, 2005]:
    • The incidence of primary Raynaud's phenomenon was 2.2% in women and 1.5% in men.
    • Of the participants who had primary Raynaud's phenomenon at baseline, 36% of both women and men had persistent symptoms at follow-up, and 64% of both women and men had remission of symptoms at follow-up.
  • A prospective study of 244 consecutive patients diagnosed with primary Raynaud's phenomenon were followed up for a mean duration of 11.2 years and found [Hirschl, 2006]:
    • The annual incidence of transition to secondary Raynaud's phenomenon was 1%.
    • The sample mainly consisted of people with moderate-to-severe symptoms, which may not be representative of the general population.
• The prognosis of secondary Raynaud’s phenomenon varies depending on the progression of the underlying cause or associated condition, and disease severity [Belch, 2017] [Stringer, 2018] [Casanegra, 2021].
  • Symptoms are usually more severe and follow a more aggressive course than in primary Raynaud's phenomenon, especially when associated with a connective tissue disorder such as systemic sclerosis [Curtiss, 2024a]. Additional predictors of attack rate, severity, and pain are low average daily temperature, stress and anxiety, older age, and female sex [Belch, 2017].
  • A systematic review of 7 observational studies (n = 4051 patients with primary Raynaud's phenomenon and 657 with suspected secondary Raynaud's phenomenon) found [Ingegnoli, 2017]:
    • The mean incidence rate of transition from primary Raynaud's phenomenon to connective tissue disease was 2.65 per 100 person-years. The risk of transition to connective tissue disease was significantly increased by the presence of nailfold capillary abnormalities and/or positive anti-nuclear antibody (ANA) titres. 
    • The mean incidence rate of transition from suspected secondary Raynaud's phenomenon to connective tissue disease was 11.01 per 100 person-years and to systemic sclerosis was 5.7 per 100 person-years.
  • A prospective study of 250 children and young people with primary Raynaud’s syndrome aged 10–20 years (mean age 15 years) followed up 6-monthly for up to 6 years found [Pavlov-Dolijanovic, 2006]:
    • 23.6% of participants had developed clinical features of a connective tissue disease over the follow-up period.
    • The mean time to development of underlying disease was 2.4 years.

What are the complications?

It is important to clinically distinguish between primary and secondary Raynaud's phenomenon, as the long-term morbidity, risk of complications, and outcomes differ between the two conditions [Choi, 2021].

• Primary Raynaud's phenomenon typically causes reversible symptoms and signs which do not progress to tissue damage. In people who are severely affected it can cause significant discomfort and reduce quality of life [Wigley, 2016; Curtiss, 2024a].
• Secondary Raynaud's phenomenon may progress to potentially permanent tissue destruction if undiagnosed and untreated, due to ongoing biochemical and structural changes in the vasculature [Curtiss, 2024a]. Complications may include:
  • Digital ischaemia causing digital pitting, digital ulceration, acute digital ischaemia with tissue necrosis or dry gangrene, resorption of underlying bone (telescoping digits), and eventual loss of digits [Belch, 2017; Herrick, 2017; Shapiro, 2017; Choi, 2021; Curtiss, 2024a; Denton, 2024].
  • Secondary infection of superficial and deep tissues including abscess formation and osteomyelitis  [Belch, 2017; Haque, 2020; Herrick, 2020; Denton, 2024].

When should I suspect Raynaud's phenomenon?

• Suspect a diagnosis of Raynaud’s phenomenon if a person presents with skin colour changes of the digits, usually precipitated by cold, or less frequently by stress or emotion.
  • There is a history of clearly demarcated blanching of the digit(s), involving volar and dorsal aspects (circumferential distribution).
  • Colour changes typically start at the tip of the finger and then spread to one or more phalanges, or to more digits.
    • The classical triphasic colour changes of blanching followed by cyanosis and erythema may not always be present.
    • The colour change is often associated with other symptoms such as transient numbness and paraesthesia of the affected finger tips, with pain on rewarming.
    • Extremities other than the digits may be affected, such as the tip of the nose, ears, tongue, lips, and areolar tissue.
• Suspect a diagnosis of secondary Raynaud’s phenomenon if any of the following are present:
  • Onset over the age of 30 years.
  • Episodes that are intense, painful, or asymmetrical.
  • Symptoms of paraesthesia, numbness, and pain which persist between attacks.
  • Evidence of an underlying cause or associated condition such as connective tissue disease.
  • Signs of a complication such as digital ischaemia.
  • Abnormal nail fold capillaries on examination and/or positive anti-nuclear antibody (ANA) titres on blood testing. See the section on Assessment for more information.
• Suspect a diagnosis of primary Raynaud’s phenomenon if there:
  • Are symmetrical symptoms, typically affecting both hands and sparing the thumbs.
  • Are reversible episodes.
  • Is no evidence of an underlying cause or associated condition.
  • Is a negative or low ANA titre (such as less than 1:40) on blood testing. See the section on Assessment for more information.

How should I assess a person with suspected Raynaud's phenomenon?

If a person has clinical features suggesting a diagnosis of Raynaud's phenomenon:

• Ask about:
  • Symptoms including increased cold sensitivity; colour change of digits or other extremities; whether symptoms are symmetrical; associated features such as numbness, paraesthesia, or pain (on rewarming or persistent); frequency and severity of episodes.
    • A typical episode lasts 15 to 20 minutes after rewarming, but may last hours.
  • Any known underlying cause or associated condition or suggestive symptoms, such as:
    • Fatigue, joint stiffness, swollen joints, sclerodactyly (puffy fingers with skin tightening), rash, photosensitivity, hair loss, oral or nasal ulceration, dry eyes or mouth, oesophageal dysmotility or acid reflux, migraine, muscle weakness or pain, peripheral oedema, breathlessness, or weight loss.
  • Any triggers such as cold exposure, emotion, drugs, vibration exposure, repetitive use of digits, or digital injury which may precipitate or exacerbate symptoms.
  • The impact on hand function and daily activities, if relevant.
  • Age at onset — can help differentiate primary from secondary Raynaud's phenomenon.
    • Primary Raynaud's phenomenon tends to present in the teens and 20s, whereas secondary Raynaud's phenomenon tends to present in older age groups.
  • Any symptoms of complications, such as digital ulceration.
  • Any family history of Raynaud’s phenomenon (more common in primary disease), autoimmune, and/or rheumatological disease.
  • Smoking and occupational history.
• Examine the person:
  • Assess the digits for skin temperature and colour change.
    • In primary Raynaud's phenomenon, physical examination is typically normal in between episodes, but fingers and toes may be cold to the touch.
    • As clinical signs may not be present at the time of assessment, ask the person to take a photograph of affected digits during an episode, if possible.
  • Assess the skin, hair, nails, and joints for signs of digital ischaemic complications such as digital pitting or ulceration.
  • Assess the skin, hair, nails, and joints for signs of an underlying cause or associated condition such as connective tissue disease, suggested by:
    • Abnormal nail fold capillaries (best viewed with a dermatoscope in primary care) —  an early sign of connective tissue disease, particularly systemic sclerosis.
    • Sclerodactyly or skin thickening and tightening elsewhere such as around the mouth or puffy fingers or toes (dactylitis); calcinosis (subcutaneous calcium deposition) — increased likelihood of systemic sclerosis.
    • Widespread telangiectasia; malar rash; joint synovitis; alopecia.
  • Check peripheral pulses in upper and lower limbs and blood pressure in both arms.
    • Asymmetrical pulses suggest proximal vessel involvement above brachial artery level, which may indicate occlusive vascular disease. See the CKS topic on Peripheral arterial disease for more information.
    • Peripheral pulses are typically easily felt and symmetrical in primary Raynaud's phenomenon.
• Consider arranging investigations in primary care to assess for possible secondary Raynaud's phenomenon, such as:
  • Blood tests for full blood count (FBC), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) inflammatory markers, thyroid function tests, and anti-nuclear antibody (ANA) titres.
    • If there is a high index of suspicion of connective tissue disease and/or the ANA screen is positive (such as an ANA titre more than 1:40), consider checking extractable nuclear antigen (ENA) antibody titres to screen for specific connective tissue diseases, depending on local laboratory availability and protocols.
  • Other tests to check for an underlying cause or associated condition, depending on clinical judgement.

What else might it be?

• Other conditions which may present similarly to Raynaud's phenomenon include:
  • Chilblains (pernio) — self-limiting painful, itchy red or purple lesions with associated swelling, typically on the finger or toe pads, nail folds, and skin of the dorsum of the feet and hands at the level of small digital joints following cold exposure; may be ulceration or blistering in severe cases. Usually resolve within 1–3 weeks.
  • Non-freezing cold injuries — usually after being cold and wet for a prolonged period. The limb shows a localized sensory neuropathy on re-warming. 
  • Frostbite injury — true tissue freezing caused by heat loss sufficient to cause ice crystal formation in superficial or deep tissues; may be associated with tissue loss, digital necrosis, and possible limb amputation.
  • Acrocyanosis — painless, persistent distal symmetrical cyanosis of the upper or all four limbs, aggravated by the cold; may be associated with hyperhidrosis due to sympathetic overdrive; more common in young women with low body mass index (BMI). No typical 'attacks', no associated numbness, no clear demarcation of skin colour change.
  • Erythromelalgia — intermittent burning pain in the extremities which is worsened by warming and relieved by cooling; with redness and heat of affected skin.
  • Paroxysmal digital haematoma — presents with sudden acute pain in a finger, less commonly palm or toe, with appearance of ecchymosis and oedema over affected area, which fade over a few days; due to spasm and rupture of a venule.
  • Haematological — malignancies; cryodiseases (cryoglobulinaemia, cold agglutinin disease), and hyperviscosity syndromes. See the CKS topic on Multiple myeloma for more information.
  • Livedo — mottled, red-to-blue netlike discolouration of the skin that can be widespread or localized, caused by deoxygenation in the superficial venous plexus. May follow vasospasm due to cold exposure, arterial embolism, increased blood viscosity, and vasculitis.
  • Peripheral nerve injury. 
  • Complex regional pain syndrome (reflex sympathetic dystrophy) — diffuse persistent pain in an extremity, often associated with vasomotor changes following an injury. See the CKS topic on Chronic pain for more information.
  • Occlusive vascular disease — for example due to vasculitis, embolism from thoracic outlet syndrome, or atherosclerosis.

Scenario: Management of Raynaud's phenomenon

From age 5 years onwards.

Nifedipine

Search strategy

Scope of search

A literature search was conducted for guidelines and systematic reviews on primary care management of Raynaud's phenomenon.

Search dates

January 2020 - September 2024.

Key search terms

The terms listed below are the core search terms that were used for EBSCOhost MEDLINE (searched 13th January 2020). These were combined with filters to identify guidelines, systematic reviews and primary care relevant literature in EBSCOhost MEDLINE. The strategy was adapted for The Cochrane Library databases. 

S3    S1 OR S2 
S2    AB raynaud* OR TI raynaud* 
S1    (MH "Raynaud Disease+") 

Sources of guidelines

• National Institute for Health and Care Excellence (NICE)
• Scottish Intercollegiate Guidelines Network (SIGN)
• Royal College of Physicians
• Royal College of General Practitioners
• Royal College of Nursing
• NICE Evidence
• World Health Organization
• Guidelines International Network
• TRIP database
• Agency for Healthcare Research and Quality
• National Health and Medical Research Council (Australia)
• Royal Australian College of General Practitioners
• British Columbia Medical Association
• Canadian Medical Association
• Alberta Medical Association
• Michigan Quality Improvement Consortium
• Singapore Ministry of Health
• National Resource for Infection Control
• RefHELP NHS Lothian Referral Guidelines
• Medline (with guideline filter)
• Driver and Vehicle Licensing Agency
• NHS Health at Work (occupational health practice)

Sources of systematic reviews and meta-analyses

• The Cochrane Library:
  • Systematic reviews
  • Protocols
  • Database of Abstracts of Reviews of Effects
• Medline (with systematic review filter)
• EMBASE (with systematic review filter)

Sources of health technology assessments and economic appraisals

• NIHR Health Technology Assessment programme
• The Cochrane Library:
  • NHS Economic Evaluations
  • Health Technology Assessments
• Canadian Agency for Drugs and Technologies in Health
• International Network of Agencies for Health Technology Assessment

Sources of randomized controlled trials

• The Cochrane Library:
  • Central Register of Controlled Trials
• Medline (with randomized controlled trial filter)
• EMBASE (with randomized controlled trial filter)

Sources of evidence based reviews and evidence summaries

• Drug and Therapeutics Bulletin
• TRIP database
• Central Services Agency COMPASS Therapeutic Notes

Sources of national policy

• Department of Health
• Health Management Information Consortium (HMIC)

Patient experiences

• Healthtalk
• BMJ - Patient Journeys

Sources of medicines information

The following sources are used by CKS pharmacists and are not necessarily searched by CKS information specialists for all topics. Some of these resources are not freely available and require subscriptions to access content.

• British National Formulary (BNF)
• electronic Medicines Compendium (eMC)
• European Medicines Agency (EMEA)
• Medicines and Healthcare products Regulatory Agency (MHRA)
• REPROTOX
• Scottish Medicines Consortium
• Stockley's Drug Interactions
• TERIS
• TOXBASE
• Micromedex
• UK Medicines Information

Stakeholder engagement

Our policy

The external review process is an essential part of CKS topic development. Consultation with a wide range of stakeholders provides quality assurance of the topic in terms of:

• Clinical accuracy.
• Consistency with other providers of clinical knowledge for primary care.
• Accuracy of implementation of national guidance (in particular NICE guidelines).
• Usability.

Principles of the consultation process

• The process is inclusive and any individual may participate.
• To participate, an individual must declare whether they have any competing interests or not. If they do not declare whether or not they have competing interests, their comments will not be considered.
• Comments received after the deadline will be considered, but they may not be acted upon before the clinical topic is issued onto the website.
• Comments are accepted in any format that is convenient to the reviewer, although an electronic format is encouraged.
• External reviewers are not paid for commenting on the draft topics.
• Discussion with an individual or an organization about the CKS response to their comments is only undertaken in exceptional circumstances (at the discretion of the Clinical Editor or Editorial Steering Group).
• All reviewers are thanked and offered a letter acknowledging their contribution for the purposes of appraisal/revalidation.
• All reviewers are invited to be acknowledged on the website. All reviewers are given the opportunity to feedback about the external review process, enabling improvements to be made where appropriate.

Stakeholders

• Key stakeholders identified by the CKS team are invited to comment on draft CKS topics. Individuals and organizations can also register an interest to feedback on a specific topic, or topics in a particular clinical area, through the Getting involved section of the Clarity Informatics website.
• Stakeholders identified from the following groups are invited to review draft topics:
  • Experts in the topic area.
  • Professional organizations and societies (for example, Royal Colleges).
  • Patient organizations, Clarity has established close links with groups such as Age UK and the Alzheimer’s Society specifically for their input into new topic development, review of current topic content and advice on relevant areas of expert knowledge.
  • Guideline development groups where the topic is an implementation of a guideline.
  • The British National Formulary team.
  • The editorial team that develop MeReC Publications.
• Reviewers are provided with clear instructions about what to review, what comments are particularly helpful, how to submit comments, and declaring interests.

Patient engagement

Clarity Informatics has enlisted the support and involvement of patients and lay persons at all stages in the process of creating the content which include:

• Topic selection
• Scoping of topic
• Selection of clinical scenarios
• First draft internal review
• Second draft internal review
• External review
• Final draft and pre-publication

Our lay and patient involvement includes membership on the editorial steering group, contacting expert patient groups, organizations and individuals.

Evidence exclusion criteria

Our policy

Scoping a literature search, and reviewing the evidence for CKS is a methodical and systematic process that is carried out by the lead clinical author for each topic. Relevant evidence is gathered in order that the clinical author can make fully informed decisions and recommendations. It is important to note that some evidence may be excluded for a variety of reasons. These reasons may be applied across all CKS topics or may be specific to a given topic.

Studies identified during literature searches are reviewed to identify the most appropriate information to author a CKS topic, ensuring any recommendations are based on the best evidence. We use the principles of the GRADE and PICOT approaches to assess the quality of published research. We use the principles of AGREE II to assess the quality of published guidelines.

Standard exclusions for scoping literature:

• Animal studies
• Original research is not written in English

Possible exclusions for reviewed literature:

• Sample size too small or study underpowered
• Bias evident or promotional literature
• Population not relevant
• Intervention/treatment not relevant
• Outcomes not relevant
• Outcomes have no clear evidence of clinical effectiveness
• Setting not relevant
• Not relevant to UK
• Incorrect study type
• Review article
• Duplicate reference

Organizational, behavioural and financial barriers

Our policy

The CKS literature searches take into consideration the following concepts, which are discussed at the initial scoping of the topic.

• Feasibility
  • Studies are selected depending on whether the intervention under investigation is available in the NHS and can be practically and safely undertaken in primary care.
• Organizational and Financial Impact Analysis
• Studies are selected and evaluated on whether the intervention under investigations may have an impact on local clinical service provision or national impact on cost for the NHS. The principles of clinical budget impact analysis are adhered to, evaluated and recorded by the author. The following factors are considered when making this assessment and analysis.
  • Eligible population
  • Current interventions
  • Likely uptake of new intervention or recommendation
  • Cost of the current or new intervention mix
  • Impact on other costs
  • Condition-related costs
  • In-direct costs and service impacts
  • Time dependencies
• Cost-effectiveness or cost-benefit analysis studies are identified where available. 

We also evaluate and include evidence from NICE accredited sources which provide economic evaluations of recommendations, such as NICE guidelines. When a recommended action may not be possible because of resource constraints, this is explicitly indicated to healthcare professionals by the wording of the CKS recommendation.

Declarations of interest

Our policy

Clarity Informatics requests that all those involved in the writing and reviewing of topics, and those involved in the external review process to declare any competing interests. Signed copies are securely held by Clarity Informatics and are available on request with the permission of the individual. A copy of the declaration of interest form which participants are asked to complete annually is also available on request. A brief outline of the declarations of interest policy is described here and full details of the policy is available on the Clarity Informatics website. Declarations of interests of the authors are not routinely published, however competing interests of all those involved in the topic update or development are listed below. Competing interests include:

• Personal financial interests
• Personal family interest
• Personal non-financial interest
• Non-personal financial gain or benefit

Although particular attention is given to interests that could result in financial gains or losses for the individual, competing interests may also arise from academic competition or for political, personal, religious, and reputational reasons. An individual is not obliged to seek out knowledge of work done for, or on behalf of, the healthcare industry within the departments for which they are responsible if they would not normally expect to be informed.

Who should declare competing interests?

Any individual (or organization) involved in developing, reviewing, or commenting on clinical content, particularly the recommendations should declare competing interests. This includes the authoring team members, expert advisers, external reviewers of draft topics, individuals providing feedback on published topics, and Editorial Steering Group members. Declarations of interest are completed annually for authoring team and editorial steering group members, and are completed at the start of the topic update and development process for external stakeholders.

Competing interests declared for this topic:

None.