Changes

July 2026 — minor update. Removed table of ABPI thresholds and added PAD threshold for PAD diagnosis.

Update

Goals

To support primary healthcare professionals to:

• Make a diagnosis of peripheral arterial disease.
• Offer appropriate initial and subsequent management.
• Manage any co-existing cardiovascular risk factors.
• Refer people with peripheral arterial disease, when appropriate, to other healthcare professionals.

Outcome measures

Audit criteria

QOF indicators

Table 1. Indicators related to peripheral arterial disease in the Quality and Outcomes Framework (QOF) of the General Medical Services (GMS) contract 2025-26.

QIPP - Options for local implementation

NICE quality standards

Peripheral arterial disease

• People who have symptoms of, or who are at risk of developing, peripheral arterial disease (PAD) are offered a clinical assessment and ankle brachial pressure index (ABPI) measurement.
• People with PAD are offered an assessment for cardiovascular comorbidities and modifiable risk factors.
• People with intermittent claudication are offered a supervised exercise programme.
• People with PAD being considered for revascularisation who need further imaging after a duplex ultrasound are offered magnetic resonance angiography (MRA).
• People with intermittent claudication are offered angioplasty only when imaging has confirmed it is appropriate, after advice on the benefits of modifying risk factors has been given and after a supervised exercise programme has not improved symptoms.

[NICE, 2014]

What is it?

• Peripheral arterial disease is a term used to describe a chronic condition where atherosclerotic obstruction (narrowing or occlusion) of the peripheral arteries affects the blood supply to the lower limbs.
  • There are numerous definitions and classification systems.  
• Peripheral arterial disease can present as: 
  • Intermittent claudication is the most common clinical symptom associated with peripheral arterial disease — walking (exercise) induced pain in the lower limbs caused by diminished circulation that is relieved by rest. 
  • Critical limb ischaemia — circulation is so severely impaired that there is an imminent risk of limb loss.
  • Chronic limb-threatening ischaemia — clinical patterns with threatened limb viability related to several factors (not only severe ischaemia). It is characterised by chronic, inadequate tissue perfusion in combination with ischaemic rest pain, with or without tissue loss (for example ulcers, gangrene) or infection. It represents the end stage of peripheral arterial disease. 
    • This newer terminology is intended to replace the concept of critical limb ischaemia. It includes a broader range of people with varying degrees of ischaemia that may delay wound healing and increase the likelihood of amputation [Conte, 2019]. We will use this terminology throughout this topic. 
  • Asymptomatic peripheral arterial disease — this is considered to be an early stage in the continuum of the condition and may progress with symptoms of intermittent claudication or chronic limb-threatening ischaemia. 
• Acute limb ischaemia is a sudden decrease in limb perfusion that threatens limb viability — decreased perfusion and symptoms and signs develop over less than 2 weeks. It is a medical emergency. 

[Conte, 2015; Gerhard-Herman, 2017; Aboyans, 2018; Morley, 2018; Conte, 2019; NICE, 2020; BMJ Best Practice, 2023; Nordanstig, 2024]

What causes it?

• Peripheral arterial disease of the lower limbs is most commonly caused by atherosclerosis (in 95% of cases), which narrows the affected arteries. This limits blood flow to the affected limb. 
  • Less common causes of peripheral arterial disease include inflammatory disorders (for example vasculitis) and non-inflammatory arteriopathies (for example fibromuscular dysplasia).
  • Chronic limb-threatening ischaemia can also be caused by:
    • Adventitial cystic disease. 
    • Buerger's disease.
    • Arterial dissection.
    • Popliteal entrapment syndrome.
    • Thromboembolism.
    • Trauma.
  • In younger people, more likely causes are genetic, congenital, immunological, infectious, or traumatic. 
• Acute limb ischaemia is caused by a sudden reduction in arterial perfusion of the limb, most commonly due to thrombosis within a diseased artery when an atherosclerotic plaque ruptures (80–85% of cases). 
  • Less common causes include:
    • Aortic dissection or embolization.
    • Cardiac embolization.
    • Graft thrombosis.
    • Hypercoagulable states.
    • Iatrogenic complications of vascular interventions.  
    • Thrombosis of a popliteal aneurysm.
    • Trauma.

[Santistevan, 2017; Aboyans, 2018; Morley, 2018; Conte, 2019; Powell, 2020; BMJ Best Practice, 2023; Nordanstig, 2024]

How common is it?

• Peripheral arterial disease is uncommon in people aged under 50 years, but increases with age [Gerhard-Herman, 2017]. 
  • Evidence from population studies suggests that about 20% of people aged over 60 years have some degree of peripheral arterial disease [NICE, 2020].
  • Men and women have a similar prevalence of peripheral arterial disease, although men have a higher prevalence of more severe or symptomatic disease [Criqui, 2015; BMJ Best Practice, 2023]. 
• Intermittent claudication is the most common initial symptom of lower limb peripheral arterial disease, but asymptomatic peripheral arterial disease is more common [Criqui, 2015; NICE, 2020]. 
  • In most studies, 1 in 3 to 1 in 5 people diagnosed with peripheral arterial disease are symptomatic [Aboyans, 2018]. 
• The prevalence of chronic limb-threatening ischaemia is low at 0.4% [Aboyans, 2018].    
• The true incidence of acute limb ischaemia is unknown [Björck, 2020], however, it is estimated at 1.5 cases per 10,000 people per year [Santistevan, 2017], but it is a frequently missed or delayed diagnosis [Brearley, 2013]. 

What are the risk factors?

• Risk factors for peripheral arterial disease are similar to those of other cardiovascular diseases. Strong risk factors include [Criqui, 2015; Foley, 2016; Aboyans, 2018; BMJ Best Practice, 2023]:  
  • Smoking — smoking is the most powerful predictor of peripheral arterial disease. There is a four-fold increase in risk due to smoking, and there is a dose-dependent association with severity. People with peripheral arterial disease who continue to smoke are at increased risk of developing claudication and chronic limb-threatening ischaemia and are twice as likely to need limb amputation compared with someone who quits.
  • Diabetes mellitus — there is a two- to four-fold increased risk of peripheral arterial disease. The UK Prospective Diabetes Study Group showed that each 1% increase in glycosylated haemoglobin levels is associated with a 28% increased risk of incident peripheral arterial disease and a 28% increased risk of death, independent of other variables such as blood pressure, serum cholesterol, age, or smoking status. 
  • Hypertension — there is an increased risk associated with hypertension with odds ratios ranging from 1.5 to 2.2.
  • Hypercholesterolaemia — elevated total cholesterol, LDL, triglycerides, and lipoprotein (a) are associated with increased risk of peripheral arterial disease.
• Other risk factors for peripheral arterial disease include [Conte, 2015; Criqui, 2015; Gerhard-Herman, 2017; Aboyans, 2018; Morley, 2018; Firnhaber, 2019; BMJ Best Practice, 2023]: 
  • Older age — prevalence increases with age.  
  • Known atherosclerotic disease elsewhere (for example coronary, carotid, abdominal aorta). 
  • Chronic kidney disease — an association has been seen in several studies, particularly in people with end-stage renal disease. 
  • Elevated plasma homocysteine levels — approximately 30-40% of people with peripheral arterial disease have high levels of homocysteine. However, there is no evidence that treatment improves clinical outcomes in people with peripheral arterial disease. 
• The odds of developing peripheral arterial disease increases in people who have more than one risk factor. One risk factor results in a 1.5-fold increase and three or more risk factors cause a 10-fold increase [Firnhaber, 2019].
• Not all people with acute limb ischaemia have risk factors [Brearley, 2013].

What are the complications?

• Complications of peripheral arterial disease include [NICE, 2020]:
  • Impairment of quality of life due to limitations in mobility.
  • Severe pain. 
  • Psychosocial consequences such as depression — this is commonly associated with advanced peripheral arterial disease [Shishehbor, 2016]. 
  • Tissue loss (ulceration and gangrene) in chronic limb-threatening ischaemia [Aboyans, 2018].
    • Risk of amputation is increased in people with chronic limb-threatening ischaemia [Gerhard-Herman, 2017]. 
    • Few people with intermittent claudication develop complications which are limb-threatening (1–3% over 5 years) [Morley, 2018]. 
  • Infection [Aboyans, 2018].
  • Procedural complications in people undergoing invasive treatments for peripheral arterial disease [Conte, 2015]. 
• People with peripheral arterial disease are also at high risk of vascular complications such as myocardial infarction, stroke, vascular dementia, renovascular disease, and mesenteric disease [Cea-Soriano, 2018; Morley, 2018]. 
  • Atherosclerosis is often generalised and, if it is present at one site, there is an increased risk of cardiovascular events [Aboyans, 2018]. 
• Complications of acute limb ischaemia include [Björck, 2020]: 
  • Reperfusion injury — this occurs when blood flow to the ischaemic limb is restored. Tissue damage is initiated in the ischaemic phase but continues, and even aggravated, after reperfusion. In some cases this can lead to multiorgan failure and cardiovascular collapse [Gerhard-Herman, 2017].  
  • Compartment syndrome — reperfusion of ischaemic muscles can cause oedema and increased compartmental pressure. This results in muscle damage, accompanied by leakage of myoglobin and creatine kinase into the circulation (rhabdomyolysis). Untreated, the extremity (usually the foot) becomes ischaemic again, and the limb may be lost. 

What is the prognosis?

• The course of peripheral arterial disease is not always predictable — it can progress gradually along a spectrum from claudication to rest pain to ischaemic ulcers or gangrene, but there may be more sudden progression [Norgren, 2007].
• Intermittent claudication has a variable prognosis. Over a 5-year period [NICE, 2020]: 
  • Most people continue to have stable claudication. 
  • 10–20% develop worsening symptoms. 
  • 5–10% develop chronic limb-threatening ischaemia. 
  • 10–15% die of cardiovascular causes.
  • 20% will have a non-fatal cardiovascular event.
  • Amputation is eventually required in around 1–2% of people with intermittent claudication. This increases to 5% in people with diabetes. 
• Chronic limb-threatening ischaemia carries a high risk of amputation and premature death [Morley, 2018]. 
  • Of people with chronic limb-threatening ischaemia, it is estimated that 50–90% will have a revascularization procedure [Abu Dabrh, 2015].
  • Around a third of people will require a lower limb amputation within a year of diagnosis without revascularization [NICE, 2020]. 
  • Overall survival is worse than for many cancers, with a 5-year all-cause mortality of 50% [Morley, 2018]. 
• Most people with peripheral arterial disease also have atherosclerotic disease of the brain or heart and are three times more likely to die of cardiovascular causes than someone without peripheral arterial disease [Foley, 2016]. 
  • Cardiovascular events are more likely in people with peripheral arterial disease, even if it is asymptomatic [NICE, 2020].
  • An ankle-brachial pressure index (ABPI) of less than 0.9 or more than 1.4 indicates the person has an increased risk of major cardiovascular events [Conte, 2015]. 
  • For people with chronic limb-threatening ischaemia, there is a three-fold excess risk of myocardial infarction, stroke, and vascular death compared with people with intermittent claudication [Aboyans, 2018]. 
• One systematic review which analysed the morbidity and mortality associated with atherosclerotic peripheral artery disease found that [Agnelli, 2020]: 
  • People with peripheral arterial disease have a high risk of all-cause and cardiovascular mortality, and the risk of stroke or myocardial infarction is at least equivalent to the risk in people with coronary artery disease.
  • Compared with an ABPI less than 0.9, the presence of chronic limb-threatening ischaemia was associated with an increased risk of all-cause and cardiovascular mortality (RR, 2.26, 95% CI, 1.77–2.89 and 1.42, 1.01–2.01, respectively), myocardial infarction (RR, 2.63, 95% CI, 1.49–4.64), major cardiovascular events (RR, 1.73, 95% CI, 1.25–2.38), and major amputations (RR, 3.85, 95% CI, 2.52–5.87). The event rates for stroke were similar.
• In acute limb ischaemia [Santistevan, 2017]: 
  • Mortality rates range from 15–20%, with about a third of deaths resulting from metabolic complications associated with revascularisation (for example acidosis and hyperkalaemia). 
  • Limb prognosis is related to the severity of arterial disease, the acuteness of ischaemia onset, and how rapidly perfusion is restored. 
  • Amputation rate relates to the time between ischaemia onset and reperfusion, increasing with longer duration of ischaemia (6% if within 12 hours, 12% within 13–24 hours,20% after 24 hours). 
• Factors associated with disease progression include increasing age, low and high ankle brachial pressure index (ABPI), male sex, smoking, diabetes mellitus, and concurrent cardiovascular disease [Sigvant, 2016].

What are the clinical features of acute limb ischaemia?

• The clinical presentation of acute limb ischaemia depends on the location and duration of the arterial occlusion, the presence of collateral circulation, and the metabolic changes related to tissue ischaemia. 
• Typical features of acute limb ischaemia include the six Ps:
  • Pain — constantly present and persistent.
  • Pallor (or cyanosis or mottling).
  • Pulselessness — ankle pulses are always absent.
  • Poikilothermia (perishing with cold).
  • Paraesthesia or reduced sensation or numbness.
  • Paralysis or power loss.
• Note: not all typical features need to be present for diagnosis — this occurs rarely; if there is severe ischaemia.    
• If there is ischaemia due to an embolus:
  • Onset is acute. 
  • The limb appears mottled and there may be a distinct demarcation between areas of perfusion and ischaemia. 
  • Vascular examination in the other leg is usually normal. 
• If there is ischaemia due to thrombosis:
  • Onset is more gradual (due to increased collateral circulation in people with pre-existing peripheral arterial disease). 
  • The leg may be bluish, and there is no distinct demarcation.  
  • Presentation is usually with worsening claudication. Pulses in the other leg may be abnormal.

What are the clinical features of intermittent claudication and chronic limb-threatening ischaemia?

• Classical features of intermittent claudication include:
  • Fatigue, discomfort, cramping or pain in the muscles of the lower extremities after walking a predictable distance that is relieved by rest (within 10 minutes) and reproduced by walking the same distance again — it is not present at rest or exacerbated by position.
    • It may also be described as aching or burning.
  • Symptoms usually occur in the distal extremity before the proximal extremity — the calves are more commonly affected than the thigh, buttocks or hips.
  • Symptoms may be unilateral or bilateral.  
  • Note that some people present with atypical symptoms, and may use terminology such as 'tired', 'giving way', 'sore', and 'hurts', rather than describing cramp. 
• Features of chronic limb-threatening ischaemia include:
  • Chronic rest pain, which may be worse at night because of the decrease in blood pressure when asleep and the loss of beneficial gravitational effects on lower limb circulation. People may report sleeping with the leg hanging out of bed, or sleep in a chair to relieve symptoms in the affected foot.
    • Note: many people do not have a history of intermittent claudication (it may not be clinically apparent in people with limited mobility, or who do not walk far enough to cause symptoms, or people with diabetic neuropathy). 
  • Dependent rubor, pallor on elevation of the extremity.
  • Skin changes including non-healing foot wounds, ischaemic ulcers and tissue loss (usually over pressure areas), and gangrene (usually of the toes).
  • Absent foot pulses — however, foot pulses may be palpable in distal embolisation. 

How should I assess a person with suspected peripheral arterial disease?

• Assess people for peripheral arterial disease if they:  
  • Have symptoms suggestive of peripheral arterial disease.
  • Have diabetes, non-healing wounds on the legs or feet, or unexplained leg pain.
  • Are being considered for interventions to the leg or foot.
  • Need to use compression hosiery.
• Take a medical history and ask about:
  • The presence and severity of possible symptoms of acute limb ischaemia, intermittent claudication, and chronic limb-threatening ischaemia. 
  • The duration of symptoms. 
  • The location and timing of symptoms (at rest or during exercise).  
  • The impact of symptoms on work, daily living, and socialising. 
  • Lifestyle habits, diet, walking performances, and physical activity. 
  • Risk factors for peripheral arterial disease. 
  • Current and previous medication.  
  • Previous vascular surgical procedures.  
  • A family history of coronary artery disease, cerebrovascular disease, aortic aneurysm, or peripheral arterial disease.
• Complete a physical examination: 
  • Examine both legs and feet for evidence of chronic limb-threatening ischaemia — for example: 
    • Dependent rubor.
    • Dry, shiny skin. 
    • Elevation pallor.
    • Hair loss over the dorsum of the foot. 
    • Muscle atrophy.
    • Thickened toenails.
    • Ulceration or tissue loss on the heel or between the toes.
  • Palpate the abdominal aorta, the femoral, brachial, popliteal, and foot pulses. 
  • Examine the cardiovascular system (including auscultation for femoral, aortic, or carotid bruits).
• Measure the ankle brachial pressure index (ABPI) — this should be undertaken by an experienced operator using validated equipment. 
  • If an experienced operator using validated equipment is not able to detect an ankle pulse on Doppler, consider the possibility of acute limb ischaemia (see Features of acute limb ischaemia) and seek immediate advice from a vascular specialist. 
• With the person resting and supine (if possible): 
  • Record systolic blood pressure with an appropriately sized cuff in both arms and in the posterior tibial, dorsalis pedis, and, where possible, peroneal arteries.
  • Take measurements manually using a Doppler probe of suitable frequency in preference to an automated system.
  • Calculate the index in each leg by dividing the highest ankle pressure by the highest arm pressure.
• Measure ankle-brachial pressure index (ABPI) using Doppler assessment to help identify peripheral arterial disease.
• ABPI should be interpreted alongside clinical findings, as it may be unreliable in people with diabetes, chronic oedema, lymphoedema, or arterial calcification.
  • Toe-brachial pressure index (TBPI) or Doppler waveform analysis may be required when ABPI is unreliable.
• An ABPI of less than 0.9 is recommended as the diagnostic threshold for peripheral arterial disease.
• Do not exclude a diagnosis of peripheral arterial disease in people with a normal or raised ABPI — if there is any doubt about the diagnosis, seek advice from a vascular surgeon. 

What else might it be?

• Acute limb ischaemia is a commonly missed diagnosis as it is often not considered. Conditions that can mimic arterial occlusion include:
  • Acute compressive peripheral neuropathy (compartment syndrome) — may present with a cold, pale, pulseless limb and tense muscle compartments (not present in acute limb ischaemia). 
  • Acute deep vein thrombosis — pulses are usually palpable unless chronic arterial occlusive disease, vasospasm, or significant oedema is also present (oedema does not occur with acute limb ischaemia). 
  • Chronic peripheral neuropathy (diabetic neuropathy) — pulses are present, unless there is also chronic arterial occlusive disease or vasospasm, and skin temperature is normal (unlike in acute limb ischaemia). 
  • Low cardiac output in conjunction with chronic lower extremity peripheral arterial disease. 
• Intermittent claudication has a number of differential diagnoses, including:
  • Foot and ankle arthritis — aching pain in the ankle and foot arch. Symptoms may be influenced by activity level, not quickly resolving, but may be relieved by not weight-bearing. 
  • Hip arthritis — aching discomfort in the lateral hip and thigh after exercise, not quickly relieved, but may improve when not weight-bearing. 
  • Nerve root compression — sharp lancinating pain, radiating down the leg, exacerbated by sitting, standing, or walking, and improved by a change in position. 
  • Spinal stenosis — often bilateral pain and weakness affecting the buttocks and posterior leg. Worse on standing, relieved by flexing the lumbar spine. 
  • Chronic compartment syndrome, venous claudication, and symptomatic Baker's cyst — these are less common. 
• Chronic limb-threatening ischaemia can be missed if symptoms are confused with other causes of foot pain, for example: 
  • Arthritis. 
  • Cellulitis.
  • Gout.
  • Plantar fasciitis.

Scenario: Acute limb ischaemia

From age 18 years onwards.

Scenario: Chronic limb-threatening ischaemia

From age 18 years onwards.

Scenario: Intermittent claudication

From age 18 years onwards.

Naftidrofuryl oxalate

Paracetamol and weak opioids

• For more information on prescribing paracetamol and weak opioids, see the CKS topic on Analgesia - mild-to-moderate pain.

Search strategy

Scope of search

A literature search was conducted for guideline and systematic reviews on primary care management of peripheral arterial disease. 

Search dates

July 2019 - March 2024

Key search terms

The terms listed below are the core search terms that were used for EBSCOhost MEDLINE (searched 12th July 2019). 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. 

S13    S1 OR S2 OR S5 OR S6 OR S7 OR S8 OR S9 OR S10 OR S11 OR S12 
S12    AB intermittent claudication OR TI intermittent claudication 
S11    AB ( ((limb* or "lower extremity") N2 (ischaemi* or ischemi*)) ) OR TI ( ((limb* or "lower extremity") N2 (ischaemi* or ischemi*)) ) 
S10    AB ( (peripheral arterial occlusi* or peripheral artery occlusi*) ) OR TI ( (peripheral arterial occlusi* or peripheral artery occlusi*) ) 
S9    AB ( (peripheral arterial ischemi* or peripheral artery ischemi*) ) OR TI ( (peripheral arterial ischemi* or peripheral artery ischemi*) ) 
S8    AB ( (peripheral arterial ischaemi* or peripheral artery ischaem*) ) OR TI ( (peripheral arterial ischaemi* or peripheral artery ischaem*) ) 
S7    AB (peripheral vascular disease*) OR TI (peripheral vascular disease*) 
S6    AB ( (peripheral arterial disease* or peripheral artery disease*) ) OR TI ( (peripheral arterial disease* or peripheral artery disease*) ) 
S5    S3 AND S4 
S4    (MH "Lower Extremity+") 
S3    (MH "Ischemia+") 
S2    (MH "Intermittent Claudication") 
S1    (MH "Peripheral Arterial 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.
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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.