Changes

July 2024 — minor update. A minor typographical error was corrected.

Update

Goals

To support primary healthcare professionals to:

• Be aware of when to suspect a diagnosis of food allergy in primary care.
• Arrange immediate ambulance transfer to Accident and Emergency if there are systemic symptoms or suspected anaphylaxis.
• Advise on prompt recognition and management of acute symptoms following accidental or new exposures.
• Offer appropriate self-management advice and information to parents and carers.
• Arrange appropriate allergy testing and/or referral to an allergy specialist, depending on clinical judgement.
• Arrange referral to a dietitian for advice on allergen avoidance and food reintroduction, if appropriate.
• Ensure the person is reviewed by a specialist or in primary care at least annually.

Outcome measures

Audit criteria

No audit criteria were found during the review of this topic.

QOF indicators

QIPP - Options for local implementation

NICE quality standards

Food allergy

• Children and young people with suspected food allergy have an allergy‑focused clinical history taken.
• Children and young people whose allergy‑focused clinical history suggests an IgE‑mediated food allergy are offered skin prick or blood tests for IgE antibodies to the suspected food allergens and likely co‑allergens.
• Children and young people whose allergy‑focused clinical history suggests a non‑IgE‑mediated food allergy, and who have not had a severe delayed reaction, are offered a trial elimination of the suspected allergen and subsequent reintroduction.
• Children and young people are referred to secondary or specialist allergy care when indicated by their allergy‑focused clinical history or diagnostic testing.

[NICE, 2018b]

What is it?

• Food allergy describes an adverse immune-mediated response, which occurs when a person is exposed to specific food allergen(s), usually by ingestion and more rarely by inhalation or skin contact [Boyce, 2010; Turnbull, 2015; NICE, 2018a; Burks, 2012].
  • Immunoglobulin (Ig)E-mediated food allergy follows exposure and sensitization to trigger food allergen(s) with the development of serum-specific IgE antibodies. It produces immediate and consistently reproducible symptoms which may affect multiple organs including the skin, gastrointestinal tract, respiratory, cardiovascular, and neurological systems.
    • Pollen food syndrome (or oral allergy syndrome) describes a localized food allergy which may occur due to cross-reactivity between aeroallergens, such as birch pollen, and raw vegetables, fruits, and nuts. As a result, pollen-sensitized people mount an IgE response to epitopes present in fruit and vegetables on oral contact [Skypala, 2022]. An epitope is a portion of a foreign protein, or antigen, which is capable of stimulating an immune response by binding to a B-cell receptor. 
  • Non-IgE-mediated food allergy involves cell-mediated mechanisms, such as food protein-induced enterocolitis syndrome which tends to occur in young children and presents with solely gastrointestinal symptoms such as vomiting with or without diarrhoea, and possible faltering growth [Turnbull, 2015; Connors, 2018].
    • See the CKS topic on Faltering growth for more information.
  • Mixed IgE and non-IgE-mediated food allergy may present as cows' milk protein allergy, eosinophilic oesophagitis, or eosinophilic gastroenteritis.
    • See the CKS topic on Cows' milk protein allergy in children for more information.
• Food sensitization describes the production of serum-specific IgE to food allergens, without the clinical symptoms of an allergic reaction on food exposure [Boyce, 2010; Turnbull, 2015].
• Food intolerances are non-immune adverse reactions to foods and/or food additives which are distinct from food allergy [Boyce, 2010; Turnbull, 2015; NICE, 2018a].
  • They often present non-specifically with gastrointestinal symptoms, headache, fatigue, and musculoskeletal symptoms. Typically, there is a delay in symptom onset and a prolonged symptomatic phase. 
  • They may overlap with symptoms of other conditions such as irritable bowel syndrome or fibromyalgia. 
    • See the CKS topic on Irritable bowel syndrome for more information.
  • The exact cause is unknown, but they may be due to enzyme deficiencies or pharmacological reactions to chemicals such as caffeine or tyramine. 

What causes it?

• Allergy may develop to almost any food, but common food allergens include: 
  • Cows' milk — see the CKS topic on Cows' milk protein allergy in children for more information.
  • Hen's eggs — there is often cross-reactivity between hens' egg and turkey, duck, and goose egg allergy. 
  • Peanuts and other legumes such as soybean, pea, and chickpea — cross-reactivity is uncommon. 
  • Tree nuts (such as walnut, almond, hazelnut, pecan, cashew, pistachio, and Brazil nuts) — there is often cross-reactivity between different tree nuts such as cashew and pistachio, and a person may be allergic to multiple different tree nuts. 
  • Crustacean shellfish (such as shrimp, crab, and lobster) and fish — there is often cross-reactivity between different shellfish, and a person may be allergic to multiple different shellfish. Similarly, there is significant cross-reactivity between different fish species. 
  • Wheat — cross-reactivity is uncommon. 
• Major allergens in Europe also include celery, mustard, sesame, lupine, and molluscan shellfish. 
• In the United States, eight major food allergens (milk, egg, peanut, tree nuts, soy, wheat, fish, and crustacean shellfish) are responsible for 90% or more of serious adverse food-induced reactions. 
• Other common cross-reactions include:
  • Between peanuts, tree nuts, and sesame. 
  • 30–50% of people with known latex allergy experience a phenomenon where latex allergens cross-react with plant-derived food allergens, resulting in allergy to banana, kiwi, avocado, tomato, potato, and chestnut, for example (so-called 'latex-fruit syndrome').
• Common raw food allergens for pollen food syndrome include cross-reactivity between:
  • Birch pollen — with apple, apricot, cherry, pear, peach, plum, carrot, celery, parsley, almond, and hazelnut.
  • Timothy grass (a common agricultural grass) — with peach, watermelon, orange, tomato, kiwi, and aubergine, bell peppers, chilli, potato and Swiss chard.

[Boyce, 2010; Longo, 2013; Turnbull, 2015; Stiefel, 2017; Ewan, 2020; Leech, 2021; Skypala, 2022]

What are the risk factors?

Risk factors for the development of food allergy include:

• Existing food allergy — the presence of a confirmed food allergy increases the likelihood of additional food allergies [Turnbull, 2015].
  • Egg allergy in infancy is associated with an increased risk of developing peanut allergy [Leech, 2021]. 
• Atopic eczema — the development of early-onset atopic eczema before 6 months of age, and severe eczema below the age of one year, are associated with the development of egg, milk, and peanut allergy [RCPCH, 2011; Burks, 2012; Leech, 2021; BMJ, 2022].
  • Peanut allergy may develop through skin sensitization in children with an impaired skin barrier function, and use of eczema cream containing peanut oil is an independent risk factor for development of peanut allergy.
• Family history of food allergy — confirmed food allergy in a parent or sibling increases the risk of food allergy [Longo, 2013; BMJ, 2022]. 
  • Peanut allergy is 7 times more likely to occur in a child with a parent or sibling who is peanut-allergic than in the general population. 
  • Monozygotic twins have been reported to have a 64% concordance rate for food allergy compared with 6.8% among dizygotic twins. 
• Family history of atopy — particularly affecting parents and/or siblings [RCPCH, 2011; Nwaru, 2014a; Turnbull, 2015].

Risk factors for severe allergy include [Turnbull, 2015; Leech, 2021; BMJ, 2022]:

• A previous severe reaction. 
• A history of asthma. 
  • Asthma is common to almost all fatal cases of anaphylaxis due to food allergy. 
• Younger age — the majority of severe non-fatal and fatal accidental reactions occur in teenagers and young adults.

How common is it?

The reported prevalence of food allergy varies depending on the definitions of food allergy used, the study population, study design, and time period assessed [Stiefel, 2017]. There is also a discrepancy between self-reported food allergy and confirmed true food allergy prevalence, with over-estimates in the literature for self-reported symptoms [Burks, 2012; Longo, 2013; Muraro, 2014]. 

• There is evidence that the prevalence of food allergy has increased since the early 1990s [Boyce, 2010; Stiefel, 2017; Spolidoro, 2023].
• Primary nut allergy affects over 2% of children and 0.5% of adults in the UK [Stiefel, 2017].
• Egg allergy most commonly presents in infancy with a prevalence of about 2% in children and 0.1% in adults [Leech, 2021].
• A European systematic review and meta-analysis of 110 studies that examined people with suspected food allergy found that the overall pooled estimate [Spolidoro, 2023]:
  • Of self-reported lifetime prevalence of any food allergy was 19.9% (18.7% for children and 22.8% for adults), and the self-reported point prevalence was 13.1% (14.2% for children and 12.3% for adults).  
  • For self-reported physician-diagnosed lifetime prevalence was 6.6% (9.3% for children and 5.0% for adults), and the point prevalence was 4.9% (3.8% for children and 6.9% for adults).
  • For point prevalence of sensitization based on specific IgE (sIgE) positivity to any food was 16.6% (18.4% for children and 11.2% for adults), and 5.7% for skin prick test (SPT) positivity (4.5% for children and 21.4% for adults).  
  • For prevalence of symptoms plus sIgE positivity to any food allergen was 2.9% (3.5% for children and 2.4% for adults), and 2.4% for symptoms plus SPT positivity. 
  • For prevalence of food challenge positivity to any food allergen was 0.8% (0.7% for children and 1.4% for adults).
• Pollen food syndrome affects about 2% of the UK population, affecting 66% of birch-allergic adults and 48% of birch-allergic children [Skypala, 2022].  

What are the complications?

The possible complications of food allergy include:

• Severe and life-threatening reactions 
  • Food allergy is the most common trigger of anaphylaxis in the community.
  • The risk of anaphylaxis depends on the specific food allergy — allergy to peanuts, tree nuts, fish, and shellfish are associated with a higher risk of anaphylaxis. See the CKS topic on Angio-oedema and anaphylaxis for more information.
  • A systematic review and meta-analysis of 13 European studies found the incidence rate of fatal food anaphylaxis in people with food allergy was 1.81 per million person-years (which is lower than the rate of accidental death in the general population) [Umasunthar, 2013].
• Stress and anxiety (affecting the child, adult, and parents/carers)
  • This may be associated with the need for constant vigilance over food choices, and risk of accidental food exposure and severe reactions. 
• Reduced quality of life 
  • The impact on social interactions, such as eating out, playing at friends' houses, attending birthday parties, and participating in school meals. 
  • The impact of peer pressure, stigma, and embarrassment about food allergy on the person. 
  • Potential social exclusion, such as being prevented from going to friends' houses, going on trips, or other activities. 
• Restricted diet and malnutrition 
  • The risk of inadequate nutritional intake and faltering growth in children, if food allergens that contribute essential nutrients are eliminated. See the CKS topic on Faltering growth for more information.

[Boyce, 2010; Longo, 2013; Muraro, 2014; Turnbull, 2015; Stiefel, 2017; Meyer, 2018; BMJ, 2022; BMJ, 2023]

What is the prognosis?

The prognosis of food allergy depends on the person's age, comorbidities, and specific causal food allergen.

• Children may outgrow their food allergy to certain foods, such as milk, egg, soy, and wheat [Boyce, 2010; Anagnostou, 2015].
  • Systematic review data suggest that 30% of egg-allergic children will continue to have persisting egg allergy after the age of 16 years. There are no data on continued resolution in young adults. However, while it persists in some and may be lifelong, many others may have partly or wholly resolving egg allergy, even in their late 20s [Leech, 2021]. 
    • At 1 year of age, complete resolution of egg allergy is more likely in children who can tolerate baked egg than those who continue to react. Children with mild/moderate egg allergy or with cutaneous reactions only are more likely to resolve. Persistence of egg allergy is associated with respiratory or multisystem symptoms, high egg-specific IgE, presence of other food allergies or atopic comorbidities.
    • Allergy to well-cooked egg resolves in about one-third of children by 3 years of age, and two-thirds by 6 years.
  • A study of children with confirmed egg allergy (n = 881, limited clinical details available) found that tolerance had developed in 4% of children by 4 years of age; 26% by 8 years; 48% by 12 years; and 68% by 16 years of age [Savage, 2007].
  • A retrospective study of children (n = 103) with wheat allergy (from clinical history and positive allergy testing) found that tolerance had developed (confirmed by oral food challenge) in 29% of children by 4 years of age; 56% by 8 years; and 65% by 12 years. The median age of resolution was 6.5 years [Keet, 2009].
• Certain food allergies are most likely to persist, such as peanuts, tree nuts, fish, and shellfish [Boyce, 2010; Anagnostou, 2015]. There are limited data on the natural history of nut allergy, so it is unknown whether tolerance develops or not [Stiefel, 2017]. 
  • In a prospective study of people aged 4–20 years with confirmed peanut allergy (n = 223), 21.5% had a subsequent negative oral challenge suggesting they had developed tolerance (median age 6 years) [Skolnick, 2001]. However, the initial diagnosis in this study was not based on an initial oral food challenge.  
  • A prospective study of children with tree nut allergy (n = 278, from clinical history and/or positive allergy testing) found that about 9% of children developed tolerance following oral food challenge [Fleischer, 2005].  
  • In a population-based prospective cohort study of children (n = 156) who had peanut allergy confirmed at one year of age by oral food challenge, 22% of children had outgrown peanut allergy by 4 years of age [Peters, 2015]. 
  • A 12-year prospective, longitudinal follow-up study of children (n = 202; median age 12.1 months) found that spontaneous resolution of peanut allergy occurs predominantly before 6 years of age, and is much less common after 10 years of age [Begin, 2013]. However, there were methodological weaknesses with this study.  

When should I suspect food allergy?

• Suspect a diagnosis of immediate IgE-mediated food allergy if there are typical clinical features:
  • Symptoms develop within seconds or minutes to 1–2 hours after ingestion of a specific trigger food, and typically resolve before 12 hours:
    • Systemic — respiratory distress, wheeze, hypotension, tachycardia or bradycardia, drowsiness, confusion, collapse and loss of consciousness, which suggests life-threatening anaphylaxis. See the CKS topic on Angio-oedema and anaphylaxis for more information on emergency management.
    • Skin — pruritus, urticaria (localized or generalized), angioedema (most commonly of the lips, face, and around the eyes), erythema, generalized itching, and flushing. See the CKS topic on Urticaria for more information.
    • Respiratory — cough, chest tightness, wheezing, hoarseness, wheeze, breathlessness, stridor; nasal discharge, congestion, nasal itching, and sneezing. See the CKS topics on Asthma and Allergic rhinitis for more information. 
    • Gastrointestinal — nausea, vomiting, diarrhoea, and abdominal pain. 
  • Symptoms suggesting a diagnosis of pollen food syndrome (also known as oral allergy syndrome) or latex-fruit syndrome:
    • Pollen food syndrome — typically mild, transient localized oropharyngeal pruritus and angioedema of the lips, oral mucosa and soft palate after ingestion of raw fruit or vegetables (for example, apples, stone fruits, kiwi, carrot, celery). Often in people with a history of allergic rhinitis. Severe reactions may be more likely in the birch pollen season, especially in people with perennial or seasonal asthma. See the CKS topic on Allergic rhinitis for more information.
    • Latex-fruit syndrome —  about 50% of people with latex allergy have food allergy due to cross-reacting allergens. A variety of foods may be involved, including banana, avocado, kiwi, melon, and chestnut. Symptoms include urticaria, angioedema, oral symptoms, or anaphylaxis.
    • Note: be aware that a diagnosis of primary nut allergy and oral allergy syndrome may co-exist.
• Consider a diagnosis of food allergy in people whose symptoms do not respond adequately to treatment for: 
  • Atopic eczema — see the CKS topic on Eczema - atopic for more information.
  • Gastro-oesophageal reflux disease — for more information, see the CKS topic on Dyspepsia - proven GORD.
  • Chronic gastrointestinal symptoms (including chronic constipation). 
• Also consider a diagnosis of food allergy in children with faltering growth — see the CKS topic on Faltering growth for more information.

How should I assess a person with suspected food allergy?

If a diagnosis of immunoglobulin (Ig)E-mediated food allergy is suspected: 

• Ask about:
  • The age symptoms started.
  • The symptoms — frequency of occurrence, speed of onset, duration, and the timing of the reaction in relation to the suspected allergen exposure. 
  • The possible causal food or foods, how much exposure causes a reaction, the form in which the food has been eaten (raw, semi-cooked, cooked, or baked), and quantity of food ingested. 
  • Any uneventful exposures to the suspected allergen before or after the reaction. 
  • The setting of reactions (such as school or home). 
  • The reproducibility of symptoms on repeated food exposure. 
  • Any response to the elimination and reintroduction of foods. 
  • Details of any previous treatment, including medication and the response. 
  • The person's feeding history (age of complementary feeding [weaning], breast- or formula-fed), weight gain, and nutritional status.
  • The mother's diet if the child is currently being breastfed.
  • Any co-factors which may increase the likelihood of a clinical reaction: age (teenager and young adults), exercise, infection, nonsteroidal anti-inflammatory drugs (NSAIDs), or alcohol. 
  • Cultural and religious factors that affect the foods they eat. 
  • Any comorbid atopic conditions such as asthma, eczema, or allergic rhinitis.
    • See the CKS topics on Asthma, Eczema - atopic, and Allergic rhinitis for more information.
  • Any family history of food allergy or atopic conditions in parents and siblings.
• Examine the person for:
  • Signs of faltering growth (in children) and malnutrition — nutritional status, including weight, length/height, and calculation of body mass index (BMI).
  • Any signs of a clinical reaction. 
  • Any signs of comorbid conditions (such as asthma, atopic eczema, and allergic rhinitis). 
• Arrange for skin prick testing and/or serum-specific IgE allergy testing to the suspected food allergens and likely cross-reactive foods, depending on local referral pathways and availability. 
  • See the section on Specialist referral for more information.
• Do not use atopy patch testing, or oral food challenges to diagnose IgE-mediated food allergy in primary care. 
• Advise the person that the following diagnostic tools are not recommended for the diagnosis of IgE-mediated food allergy:
  • Food elimination diets.
  • Serum-specific immunoglobulin (Ig)G testing. 
  • Vega testing (electroacupuncture devices).
  • Applied kinesiology (muscle strength testing). 
  • Hair analysis (assessing mineral content). 

What else might it be?

Conditions which may present similarly to IgE-mediated food allergy include:

• Acute spontaneous urticaria and angioedema — this describes symptoms without an allergic trigger, often following viral infection.
  • It should be suspected if there are persistent symptoms for days or weeks despite allergen avoidance, or lack of symptoms following future ingestion of the suspected allergen. 
  • See the CKS topics on Urticaria and Angio-oedema and anaphylaxis for more information.
• Carcinoid syndrome — may present with watery diarrhoea and upper body flushing. Symptoms may be provoked by eating (especially cheese) or alcohol ingestion. 
• Food intolerance — this describes non-immune, non-specific food reactions which may be related to enzyme deficiencies such as lactase deficiency (causing diarrhoea, abdominal pain, and increased flatus after ingestion of dairy products); pharmacological causes (such as caffeine or tyramine in cheeses);  or have no clear mechanism (including reactions to food additive flavours and preservatives, such as glutamates and sulphites). 
  • It should be suspected if there is a delay in symptom onset and prolonged symptoms. 
  • People with irritable bowel syndrome may report increased symptoms following foods rich in carbohydrates, fatty food, coffee, alcohol, and spices. See the CKS topic on Irritable bowel syndrome for more information.
• Food poisoning and toxic reactions — including scombroid poisoning, which may present with paraesthesia, burning sensations, headaches, and itch after spoilt food ingestion.
  • Scombroid poisoning is due to bacterial production of excess amines, particularly histamine, on food. Mostly associated with dark-fleshed fish, including tuna, mackerel, sardines, anchovy, and mahi-mahi fish.
  • See the CKS topic on Gastroenteritis for more information on food poisoning.
• Food refusal or aversion — be aware that in young children, food allergy may present as food refusal due to symptoms the child cannot articulate, such as oral tingling and burning, difficulty swallowing, abdominal pain, or nausea. 

Other conditions which may have some similar features to food allergy include: 

• Acute asthma exacerbation — for more information, see the CKS topic on Asthma.
• Atopic dermatitis — for more information, see the CKS topic on Eczema - atopic.
• Coeliac disease — for more information, see the CKS topic on Coeliac disease.
• Gastroenteritis — for more information, see the CKS topic on Gastroenteritis.
• Gastro-oesophageal reflux disease — for more information, see the CKS topic on Dyspepsia - unidentified cause.
• Inflammatory bowel disease — for more information, see the CKS topics on Crohn's disease, and Ulcerative colitis.
• Irritable bowel syndrome — for more information, see the CKS topic on Irritable bowel syndrome.
• Urticaria — for more information, see the CKS topic on Urticaria.

Scenario: Management

From age 1 month onwards.

Chlorphenamine

Cetirizine

• For prescribing information, see the section on Oral antihistamines in the CKS topic on Allergic rhinitis.

Loratadine

• For prescribing information, see the section on Oral antihistamines in the CKS topic on Allergic rhinitis.

Search strategy

Scope of search

A literature search was conducted for guidelines and systematic reviews on primary care management of food allergy.

Search dates

August 2018 - May 2023

Key search terms

The terms listed below are the core search terms that were used for EBSCO MEDLINE (searched 16th August 2018). These terms were combined with search filters for systematic reviews and guidelines in EBSCO MEDLINE. The strategy was adapted for The Cochrane Library databases. 

S3 S1 OR S2

S2 AB ( (( food* or egg* or fish or shellfish or crustacean* or mollusc or peanut* or lupin or mustard or wheat or soya or sesame or tree nut or pollen-food*) N3 (allerg* OR hypersensitivit* )) ) OR TI ( (( food* or egg* or fish or shellfish or crustacean* or mollusc or peanut* or lupin or mustard or wheat or soya or sesame or tree nut or pollen-food*) N3 (allerg* OR hypersensitivit* )) ) 

S1 (MH "Food Hypersensitivity+")

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
• Institute for Clinical Systems Improvement
• 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

• Bandolier
• 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)
• LactMed
• 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.