Changes

January 2024 — reviewed. A literature search was conducted in December 2023 to identify evidence-based guidelines, UK policy, systematic reviews, and key randomized controlled trials published since the last revision of this topic. No significant changes to recommendations have been made.

Update

Goals

To support primary healthcare professionals to:

• Be aware of when to suspect a diagnosis of febrile seizure.
• Identify which children should be admitted to hospital for further assessment.
• Provide self-management advice and information to parents and carers.
• Advise parents and carers about the immediate management of possible future febrile seizures.

Outcome measures

Audit criteria

QOF indicators

QIPP - Options for local implementation

NICE quality standards

What is it?

• A febrile seizure is defined as a seizure accompanied by fever (temperature higher than 38°C by any method), without central nervous system infection, which occurs in infants and children aged 6 months to 5 years [AAP, 2011; Wilmshurst, 2015].
• Febrile seizures may be classified as simple or complex depending on the seizure duration, clinical features, and recurrence pattern  [AAP, 2011; Patel, 2015; Leung, 2018; Eilbert, 2022]:
  • Simple febrile seizures are isolated, generalized, tonic-clonic seizures lasting less than 15 minutes that do not recur within 24 hours or within the same febrile illness, with complete recovery within 1 hour.
  • Complex febrile seizures have one or more of the following characteristics: focal features (usually movement limited to one limb or one side of the body), duration of more than 15 minutes, recurrence within 24 hours or within the same febrile illness, or recovery not complete within an hour.
• Febrile status epilepticus describes a prolonged seizure, but the precise definition varies. The majority of the literature on febrile seizure describes febrile status epilepticus as a febrile seizure that lasts for 30 minutes or longer, or where there are a series of seizures without full recovery in between that last for 30 minutes or longer [Patel, 2015; Leung, 2018; Eilbert, 2022]. However, many guidelines, such as those from the National Institute of Health and Care Excellence (NICE) and the Resuscitation Council UK, define convulsive status epilepticus as seizures lasting 5 minutes or more [NICE, 2022; Resuscitation Council UK, 2023]. The International League Against Epilepsy (ILAE) proposed a definition incorporating the recommendations that 5 minutes is the time after which treatment should be given and that 30 minutes is the time after which there are risks of long-term consequences [Trinka, 2015]. It is generally agreed, however, that once a seizure has lasted 5 minutes, it is likely to be prolonged, and treatment protocols all use a 5-minute definition to minimize the risk of the seizure lasting to a point which risks adverse outcomes [Glauser, 2016; Messahel, 2022].

What causes it?

The exact cause of febrile seizures is unknown, but it is thought to be an age-dependent response of the immature brain triggered by a combination of genetic predisposition and environmental factors (fever and its causes) [Patel, 2015; Leung, 2018; Sawires, 2022].

• Genetic
  • About one-third of children with febrile seizures have a positive family history of seizures [Leung, 2018; Eilbert, 2022].
  • The background prevalence risk of 1 in 30 rises to 1 in 5 if one sibling is affected and 1 in 3 if both parents and a sibling have been affected [Patel, 2015].
  • The concordance rate is between 35–69% and 14–20% in monozygotic and dizygotic twins, respectively [Leung, 2018].
• Environmental 
  • Viral infection — this is the cause of fever in 80% of cases, with human herpes virus 6 (HHV-6), which causes roseola infantum (sixth disease) and influenza viruses being common triggers, along with respiratory syncytial virus, adenovirus, enteroviruses, and rhinoviruses [Leung, 2018; Sawires, 2022].
  • Other infections — any febrile illness may cause febrile seizures. Viral upper respiratory infections, otitis media, lower respiratory tract infections, urinary tract infections, and gastroenteritis are all potential causes [Patel, 2015; Leung, 2018].
  • Post-immunization (infrequent) — febrile seizures may occur following immunization, but conversely, immunization helps to prevent illnesses which may be associated with febrile seizures and so may reduce the risk overall [Sawires, 2022].  Vaccination with diphtheria-tetanus-pertussis and measles-mumps-rubella (MMR), for example, may be associated with a very small increased risk of febrile seizure. However, this is not a contraindication to vaccination, and childhood vaccinations should be completed as normal [Leung, 2018; Smith, 2019]. A 2021 Cochrane review estimated the risk of febrile seizures attributable to the MMR vaccine as 1 per 1150 to 1 per 1700 administered doses [Di Pietrantonj, 2021]. See the CKS topic on Immunizations - childhood for more information.

What are the risk factors?

Strong risk factors for a first febrile seizure include [BMJ Best Practice, 2022; Eilbert, 2022]:

• Family history of febrile seizure in first-degree relatives.
• Young age. Incidence is rare before 6 months and after the age of 5.
• A high peak temperature (rather than the rapidity of the temperature rise) [Leung, 2018]. The risk increases with increasing height of temperature.
• Viral infection.

Weaker risk factors for a first febrile seizure include [Smith, 2019; BMJ Best Practice, 2022; Sawires, 2022]:

• Prematurity and underlying neurological deficits or neurodevelopmental delay.
• Maternal smoking during pregnancy.
• Iron deficiency.
  
  • Meta-analyses show that iron deficiency anaemia and poor iron indices are associated with an increased risk of febrile seizure [Kwak, 2017; Sulviani, 2023].
• Zinc deficiency.
  • Results have been inconsistent, but there is some evidence to suggest that there may be an association between zinc deficiency and febrile seizures [Saghazadeh, 2015; Heydarian, 2020].

How common is it?

The prevalence of febrile seizures varies in the literature depending on the definition used, the age of the child, the inclusion criteria, and the geographic region studied [Patel, 2015; Mewasingh, 2020].

• Febrile seizures are the most common form of childhood seizure up to the age of 5 years [Eilbert, 2022; Sawires, 2022].
  • A UK national cohort study of 13,135 children followed up from birth to 5 years with a health questionnaire found 2.3% had febrile convulsions, and 20% of these presented with a complex febrile seizure [Verity, 1985]. This is consistent with the 2 – 5% incidence in the USA and Western Europe, which is widely quoted in the literature [AAP, 2011; Patel, 2015; Mewasingh, 2020; BMJ Best Practice, 2022; Eilbert, 2022; Sawires, 2022]. Higher incidence rates are quoted in some other areas, notably Japan and Guam.
  • Onset is rare after 5 years of age [BMJ Best Practice, 2022].
  • Peak incidence is between 12–18 months of age [Sawires, 2022].
  • Some studies have found equal incidence between genders, whereas others have found a higher incidence in boys [Leung, 2018; Sawires, 2022; Eilbert, 2022].
• Around 70% of febrile seizures are simple, 25% are complex, and 5% are categorized as febrile status epilepticus [Eilbert, 2022].
  • Febrile status epilepticus is the most common cause of status epilepticus in children [Eilbert, 2022; Sawires, 2022].

What are the complications?

Febrile seizures are generally benign with a normal cognitive outcome [Wilmshurst, 2015; BMJ Best Practice, 2022].

Outcome studies may be confounded by whether children with significant pre-existing neurological or neurodevelopmental disorders are excluded, as well as by varying and evolving definitions of febrile status epilepticus used [Mewasingh, 2020].

Possible complications following febrile seizure include:

• Parental/carer anxiety
  • This may be related to concern over recurrent episodes, how to manage an acute seizure, or fears about subsequent complications, and the family's quality of life may be adversely affected [Leung, 2018; Mewasingh, 2020].
• Febrile status epilepticus
  • This accounts for 25 to 52% of all status epilepticus in children and about 5% of all febrile seizures [Patel, 2015; Eilbert, 2022; Sawires, 2022]. Figures in the literature vary, however, due to differing use of the definition and other study inclusion factors [Mewasingh, 2020; Messahel, 2022].
  • It is a risk factor for further prolonged seizures [Patel, 2015].
  • Prognosis worsens with duration [Trinka, 2015; Messahel, 2022]. It also worsens in the presence of pre-existing profound comorbidity [Pujar, 2018; Mitchell, 2021; Messahel, 2022].
  • There is a theorized risk of associated hypoxia, brain injury, hippocampal abnormalities, and an increased risk of temporal lobe epilepsy. However, the evidence in the literature is conflicting [Patel, 2015; Leung, 2018; Mewasingh, 2020; BMJ Best Practice, 2022].
• Epilepsy
  • There is a small increased risk of epilepsy in children who have had a febrile seizure, which varies in the literature depending on the type of seizure and duration of follow-up in studies [Leung, 2018].
  • Around 1% – 2% of children with simple febrile seizures go on to develop epilepsy, and 6% - 8% of those with complex seizures [Patel, 2015; Eilbert, 2022].
  • Risk factors for the development of epilepsy include [Smith, 2019; Eilbert, 2022]:
    • Short duration of fever (less than 1 hour) before the seizure.
    • Complex febrile seizures.
    • Family history of epilepsy.
    • Neurodevelopmental abnormality before the onset of febrile seizures, such as cerebral palsy or hydrocephalus.
• Neurological, cognitive and memory impairments
  • Variations with the inclusion of children with pre-existing neurological disorders lead to the confounding of study outcomes. However, it seems that short febrile seizures are not associated with long-term neurological or cognitive impairments, whereas this is more controversial for children who have had febrile status epilepticus [Mewasingh, 2020].

What is the risk of recurrence?

Febrile seizures are usually self-limiting, and most children have normal growth and development.

Following a first febrile seizure, there is approximately a 32% risk of a recurrence.

• If febrile seizures are recurrent:
  • About 75% of recurrences will occur within one year of the first febrile seizure.
  • About 90% will occur within two years.
• Risk factors for recurrent febrile seizures include:
  • Early onset under 18 months of age.
    • 50% of children aged less than 12 months and 30% of children aged more than 12 months have recurrent febrile seizures.
  • Family history of febrile seizures in a first-degree relative.
  • Low-grade fever associated with seizure onset (less than 39°C).
  • Short duration of fever before the seizure (less than 1 hour).
  • Multiple seizures in 24 hours or during the same febrile episode.
  • Attendance at a daycare nursery — presumed increased viral exposure and frequent febrile illness.
  • Note: the greater the number of risk factors, the higher the recurrence rate. Children with no risk factors have around a 4 to 14% chance of recurrence, whereas those with all the risk factors have up to an 80% chance of recurrence.

[Patel, 2015; Wilmshurst, 2015; Leung, 2018; Smith, 2019; Eilbert, 2022]

When should I suspect a febrile seizure?

Suspect a diagnosis of febrile seizure if a child has a fever or febrile illness and a reported or witnessed seizure. Typical features include:

• The child is aged 6 months to 5 years.
• The seizure occurs in the context of a febrile illness, typically within the first day of the illness and often soon after the onset of the fever.
• Fever is high; on average 39°C.
• The child may have had a previous febrile seizure.

Typical features of a simple febrile seizure include:

• The seizure usually lasts less than 5 minutes and rarely lasts more than 10 minutes.
• The seizure is a generalized tonic-clonic type (muscle stiffening followed by rhythmical jerking or shaking of the limbs, which may be asymmetrical); twitching of the face, rolling back of the eyes, staring and losing consciousness.
• There may be foaming at the mouth, difficulty breathing, pallor, or cyanosis.
• A brief post-ictal period of drowsiness, irritability, or confusion, with complete recovery within 1 hour.

Typical features of a complex febrile seizure include one or more of the following:

• A partial onset or focal feature (movement limited to one side of the body or one limb).
• The seizure lasts more than 15 minutes.
• There is seizure recurrence within 24 hours or within the same febrile illness.
• There is incomplete recovery within 1 hour, and there may be prolonged post-ictal drowsiness or transient hemiparesis (Todd's palsy).

How should I assess a child with a suspected febrile seizure?

If a diagnosis of febrile seizure is suspected on the basis of clinical features, assess the child for the underlying cause of fever and to exclude an alternative condition.

• Assess for:
  • Red flag symptoms and signs suggesting a serious or life-threatening cause such as meningitis/meningococcal disease or encephalitis, and manage appropriately. See the CKS topics on Feverish children - risk assessment and management and Meningitis - bacterial meningitis and meningococcal disease for more information.
  • Other conditions that may mimic a febrile seizure, and manage appropriately.
• Ask about:
  • If fever was associated with the seizure.
    • Reported parental perception of fever should be accepted as a valid indicator of fever.
    • Be aware that fever can occur any time during or after a seizure, and the majority of febrile seizures occur within 24 hours of fever onset.
  • When the fever started, peak temperature and duration, and any associated symptoms to suggest an underlying cause of febrile illness.
  • The relationship of the onset of fever to the seizure.
  • The characteristics and duration of the seizure to help classify whether it is simple or complex. 
  • The duration of any post-ictal drowsiness.
  • Any previous seizure episodes.
  • Any recent antibiotic use (may mask signs of central nervous system infection).
  • Any recent immunizations, missed immunizations, or unknown immunization history. See the CKS topic on Immunizations - childhood for more information.
  • Neurodevelopmental history and any concerns.
  • Whether the child attends daycare such as nursery (source of potential exposure to infection).
  • Any family history of febrile seizures or epilepsy.
• Examine the child:
  • Assess the level of consciousness and check for any focal neurological deficit such as weakness of the hand, arm, or leg.
  • Check the temperature after the seizure has ended.
    • A temperature of more than 38°C is generally considered significant.
  • Assess fluid status and for signs of dehydration. See the CKS topic on Feverish children - risk assessment and management for more information.
  • Assess for other signs to identify the underlying cause of febrile illness, and manage appropriately. See the CKS topics on Feverish children - risk assessment and management for more information.
  • Assess for stigmata of a neurocutaneous or metabolic disorder suggesting an alternative cause for seizure.
• Be aware that investigations are not usually needed in primary care.
  • Consider measuring blood glucose if a child cannot be roused or is having an acute seizure episode, if possible and appropriate.
  • Consider urine dipstick analysis and urine microscopy and culture if there is no clear focus for infection, and the underlying cause of fever is uncertain. See the CKS topic on Urinary tract infection - children for more information.

What else might it be?

Other conditions that may present similarly to a febrile seizure include:

With fever

• Central nervous system infection, such as bacterial or viral meningitis or encephalitis. See the CKS topic on Meningitis - bacterial meningitis and meningococcal disease for more information.
  • Since the introduction of routine vaccines for Haemophilus influenzae type b and pneumococcal and meningococcal disease, the incidence of bacterial meningitis is significantly lower, but it remains a significant differential to exclude. 
  • A 2013 systematic review found the overall pooled prevalence of bacterial meningitis was 0.2% in children with a first simple febrile seizure and 0.6% in children with a first complex febrile seizure.
  • Red flags include irritability, neck stiffness, petechial rash, photophobia, bulging fontanelle, decreased level of consciousness, prolonged post-ictal period, and focal neurological deficit (lasting more than one hour).
    • Be aware that signs of meningeal irritation may be subtle or absent in children less than 12–24 months of age.
• Rigors or delirium (acute confusional state). See the CKS topic on Delirium for more information.
• Shivering (may occur with or without fever) — a perception of cold and involuntary muscle tremors that persist for several minutes. There is no loss of consciousness or involvement of facial or respiratory muscles.
• Febrile myoclonus — a benign disorder causing myoclonic jerks usually involving the upper limbs during fever. They may last from 15 minutes to several hours.

Without fever

• Syncope — a transient loss of consciousness due to insufficient cerebral blood flow, often caused by hypotension. It is characterized by a rapid onset, short duration, and spontaneous complete recovery. 
• Breath-holding spells or reflex anoxic seizures — brief, involuntary cessation of breathing often triggered by sudden, unexpected fright, fear, or pain. May present with pallor or cyanosis and low tone, with possible loss of consciousness and transient tonic clonic movements if the apnoea is prolonged.
• Head injury. See the CKS topic on Head injury for more information.
• Hypoglycaemia or other metabolic disorders, such as mitochondrial cytopathy — metabolic disorders may present with developmental delay, faltering growth, hepatosplenomegaly, and micro or macrocephaly.
• Drug use or withdrawal. See the CKS topic on Poisoning or overdose for more information.
• Epilepsy — suspect if there is no compelling history of fever, the seizure was complex, there were post-ictal signs, or there is a neurodevelopmental delay. See the CKS topic on Epilepsy for more information.
• Epilepsy syndromes, such as:
  • Dravet syndrome (severe myoclonic epilepsy of infancy) — a neurodevelopmental disorder characterized by prolonged intractable seizures initially triggered by fever. Typically, over time, seizures change to become myoclonic and later focal, with developmental delay associated.
  • Genetic epilepsy with febrile seizures plus (GEFS+) — an autosomal dominant disorder where seizures continue beyond 5 years of age, and afebrile seizures may also occur.
• Other neurological conditions such as cerebral palsy or neurocutaneous syndromes where seizures may form part of the condition:
  • Sturge-Weber syndrome may be suggested by a unilateral port-wine stain over the trigeminal area.
  • Tuberous sclerosis may be suggested by facial angiofibroma, shagreen or leather patches, periungual fibromas, and hypopigmented macules ('ash-leaf spots').
  • Neurofibromatosis may be suggested by cafe au lait spots, intertriginous freckling, iris hamartomas, and subcutaneous nodules.

Scenario: Acute management of febrile seizure

From age 6 months to 6 years.

Scenario: Management after a febrile seizure

From age 6 months to 6 years.

Search strategy

Scope of search

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

Search dates

October 2018 - December 2023

Key search terms

The terms listed below are the core search terms that were used for EBSCO MEDLINE (searched 11th October 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 ( (febrile or fever* or pyrexia*) N2 (seizure* or convulsion* or fit or fits) ) OR TI ( (febrile or fever* or pyrexia*) N2 (seizure* or convulsion* or fit or fits) ) 
S1 (MH "Seizures, Febrile") 

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.