Author: Nial Mullen / Editor: Nicola McDonald / Reviewer: Mohamed Waseem, Peter Lynas / Codes: MHC6, MHP3, SaC1, SaC2, SaP2, SLO1, SLO5, SLO7Published: 26/04/2021

FII is a broad term to describe a group of behaviours by parents or caregivers which cause harm to children [1].

These behaviours include [2,3]:

  • Fabrication (invention) of symptoms or signs
  • Fabrication of supporting evidence, e.g. seizure diaries
  • Direct induction of illness, e.g. smothering, poisoning

Illnesses may include practically any condition [1]:

  • Medical
  • Surgical
  • Psychiatric
  • Physical disability
  • Learning difficulties and special educational needs


This term has replaced ‘Munchausen syndrome by proxy [4,5]. This term was thought to be unhelpful because:

  • It suggested a single parental diagnosis to explain behaviours [1]
  • It takes the focus away from the potential harm to the child [1]
  • It does not account for grey areas where it is unclear if the carer genuinely believes the child to be unwell or is anxious, misinformed or deluded [2]

FII should be used as it is a descriptive term which keeps the focus on establishing what has happened to the child.

“The determination of what, if any, harm has been caused to the child is more important than semantic debates” [2]

FII describes a spectrum of behaviours.


This is the invention of symptoms or signs in the child. The caregiver provides a false story to health professionals. Harm comes to the child through unnecessary interventions, e.g. invasive tests, medication, surgery [1]

Verbal fabrication with supporting evidence

This occurs when verbal fabrications are accompanied by false specimens and/or documents, e.g. manufactured kidney stones, falsified seizure records [1].

Induction of illness

Deliberate causation of signs or symptoms in the child by the caregiver. Causes direct harm to the child:

  • BRUE (Brief resolved unexplained event is a current term for ALTE)
  • Administration of noxious substances or poisons
  • Excess use of ordinary substances, e.g. salt poisoning. Salt poisoning can be differentiated from other causes of hypernatraemia, e.g. diabetes insipidus as it causes hypernatraemia, weight gain and a raised urinary (Na+) [6]
  • Excess use of medication
  • Use of medically provided portals, e.g. gastrostomies, central lines to administer toxic or infected material [1]

Obstetric fabrication or induction

This occurs when a pregnant woman falsely describes or induces problems with her pregnancy. This may result in premature delivery, loss of fetus or other harm.

FII co-existing with chronic illness

Co-existing chronic illness is present in many cases of FII [4]. This may make FII more difficult to identify [3].

It is difficult to perform epidemiological studies of child abuse in general and FII in particular.

  • One BPSU [4] study puts the figure at 0.5/100,000 for under 16 year olds
  • The figure for children under 1 year rises to 2.8/100,000
Age range
  • FII has it’s onset in early years [2]
  • The majority of cases are <5 years of age [4]
  • The median age at diagnosis in the BPSU study was 21.8 months [4]
Position in family
  • Several children in a family may be at risk or just one [1]
Perpetrator characteristics
  • Most often the mother – >80% of cases [1,2,4]
  • May have existing mental health disorders, e.g. somatising and somatoform disorders, eating disorders, alcohol and drug use [2]
  • However, most are not obviously deluded or identifiably mentally unwell [1]
  • They may have personal histories of physical or sexual abuse as a child (25%) or being in local authority care [2]
  • Previous paramedical training is not necessary: 7 – 20% [2]
  • May seem caring and knowledgeable and can be persistent/demanding [1]
  • May be skilled at concealing activities and misleading professionals [3]
  • May deny activities when challenged and may seek alternative health care or move to another area thus continuing the risk to the child [3]

Children may adopt parents’ perception of the illness and comply with bogus symptoms [3]. Thus they may acquiesce or even collude in the falsification [1]. Despite this it remains important that the child is asked for their account [3]. This may result in a disclosure or an account at variance with the carer’s.

The range of collusive behaviours includes [2]:

  • Unawareness – the child has no knowledge of what is happening. e.g. infants, poisoning
  • Passive acceptance: the child is aware what is happening but does not resist
  • Active participation: the child participates in creating the false story or signs
  • Self harm: adolescents may proceed to somatising behaviour [2] and self harm

Collusion occurs for many reasons, e.g. naivety, fear of abandonment, re-enforcing of the relationship with their caregiver when the sick role is adopted [3].

These are complex interactions which are likely to require a full family assessment.

FII is a form of child abuse.

It results in short term and/or long term harm to the child:

  • This may be physical morbidity or mortality related to the direct induction of illness. e.g. suffocation or poisoning. This includes death and serious physical injury
  • Fabrication results in harm to the child because of iatrogenic morbidity caused by unnecessary investigations, treatments and hospital admissions
  • FII also places restrictions on normal childhood development such as:
    • Reduced school attendance
    • Limited/no involvement in sporting or social activities
    • Anxiety over health and adoption of the sick role
    • Placement in special schools, adoption of special educational requirements
  • Long term emotional and psychological development may be impaired as a result of the abnormal relationship with the perpetrator [2]
  • There can be overlap with other forms of abuse:
    • Once FII is identified there is a significant risk of further abuse [1,2]
    • A significant percentage of those who did not suffer physical harm may become victims of other forms of abuse, e.g. neglect or physical abuse [7]

FII can cause death and disability as well as physical, emotional and psychological problems.

The diagnosis of FII can be extremely difficult. Health Professionals evaluating children should be aware of the possible presenting features and include FII in the differential diagnosis along with other acute medical conditions.

Behaviours that should raise concern include [2]:

  • Reported symptoms and signs not explained by any medical condition [2]
  • Physical examination and investigations that do not explain reported symptoms [2], e.g. normal peak flow and minimal wheeze despite reported severe asthma attacks
  • Inexplicably poor response to prescribed medication [2], e.g. persistent seizures despite anti-epilepsy medication
  • Acute symptoms observed in the presence of the carer that are not seen in their absence [2], e.g. seizures seen at home but not at school or in hospital
  • Limitation in the child’s activities in excess of what might be expected for their condition [2], e.g. partial or no school attendance; special aids e.g. wheelchairs for ambulant children
  • Further objective evidence of fabrication, e.g. different histories from child and mother or biologically implausible symptoms, e.g. reports of massive fluid losses without any weight loss [2]
  • Disclosure from the child or another relative that the caregiver may be responsible for the child’s illness
  • Caregivers who seek multiple opinions inappropriately. The child may have seen many different health professionals in different settings and varied geographical locations [2]
  • Common presenting complaints include [4]: Seizures, BRUE, drowsiness, GI bleeds, and feeding difficulties. However FII can present with any symptom

FII is a clinical diagnosis. It is based on a full consideration of the clinical features, past medical and obstetric histories, examination findings and test results. The diagnosis is unlikely to be made on a single finding or consultation.

If you suspect FII:

  • The safety of the child is paramount especially with regard to poisoning, suffocation or other physical induction of illness [2]
  • Always discuss your concerns with senior colleagues. These include the paediatric registrar, the duty consultant, the named health professionals for child protection, senior nursing staff [1]
  • Do not challenge the caregiver directly as they may break contact with medical staff and thus put the child at increased risk
  • If immediate protection is required, i.e. you suspect the child to be at risk of harm, then local and national guidelines should be followed. This will include consideration of siblings
  • Ensure thorough and accurate documentation of all consultations including the child’s account [1].This may include noting abnormal interaction between the child and carer or an unusual response by the carer to events
  • A multi-agency strategy meeting will subsequently decide how best to investigate concerns and protect the child
  • Subsequent diagnosis relies on a meticulous chronology of events. This includes a review of all available health records. Thus good inter-agency co-operation is vital
  • Further investigations may include DNA sampling, toxicology or covert video surveillance. These are infrequently needed and should follow evidence based guidelines [2]

“Detailed accurate informative medical records are pivotal to the management of an FII case”

Covert video surveillance (CVS) is the video and audio recording of interactions between a child and his or her caregiver without the knowledge of the carer [8].

This is a technique which has been open to much debate [8].

It is an option available to child protection agencies when concerns regarding child abuse cannot be resolved in any other way [2].

CVS is agreed to be an acceptable diagnostic tool in a small number of children presenting with an apparent life threatening event where child abuse is strongly suspected [8].

CVS may reveal FII or it may reveal a medical cause for the child’s illness [2]. In some cases the use of CVS may also prevent the separation of children from innocent parents [8].

CVS should only be carried out by the police [2]. It must follow evidential rules.

Use of CVS should follow local and national guidance [2].

Key Learning Points

  • FII refers to a broad spectrum of presentations ranging from over-anxiety to direct induction of illness
  • Any disorder may be fabricated or induced. This includes medical and surgical as well as psychiatric and developmental
  • The term Munchausen Syndrome by Proxy is no longer used
  • Victims of FII are most commonly of pre-school age
  • The offenders of FII may be any carer for the child but it is most often the mother
  • FII causes harm to children which may be physical or psychosocial. Health professionals may be the instruments of harm by carrying out unnecessary investigations and procedures
  • Children may collude in FII making the diagnosis more difficult
  • Recognition and diagnosis of FII is rarely straightforward. Clinicians should be aware of possible presenting features
  • If FII is suspected, thorough documentation and good inter-agency communication are vital. The key to diagnosis is likely to be a meticulous chronology of events
  • CVS should be used more often
  1. Royal College of Paediatrics and Child Health. Child Protection. RCPCH, 2007. View document
  2. Royal College of Paediatrics and Child Health. Fabricated or Induced Illness by Carers (FII): A Practical Guide for Paediatricians. RCPCH, 2009. (Page 22, Table 3) View document
  3. Royal College of Paediatrics and Child Health. Perplexing Presentations (PP)/Fabricated or Induced Illness (FII) in Children Guidance. RCPCH, 2021. View document.
  4. McClure RJ, Davis PM, Meadow SR et al. Epidemiology of Munchausen Syndrome by Proxy, non accidental poisoning and non accidental suffocation. Arch Dis Child 1996;75:57-61. View article
  5. Meadow R. Munchausen syndrome by proxy. The hinterland of child abuse. Lancet 1997;2(8033):343-345. View abstract
  6. Coulthard MG, Haycock GB. Distinguishing between salt poisoning and hypernatraemic dehydration in children. BMJ 2003;326:157-160. View article
  7. Davis P, McClure RJ, Rolfe K et al. Procedures, placement and risks of further abuse after Munchausen Syndrome by Proxy, non accidental poisoning and non-accidental suffocation. Arch Dis Child 1998;78(3):217-221. View article
  8. Shabde N. Craft AW. Covert video surveillance: an important investigative tool or a breach of trust? Arch Dis Child 1999;81:291-294. View article
  9. Maguire S, Mann MK, Sibert J et al. Are there patterns of bruising in childhood which are diagnostic or suggestive of abuse? A systematic review. Arch Dis Child 2005;90(2):182-186 View article
  10. Maguire S, Mann MK, Sibert J et al. Can you age bruises accurately in children? A systematic review? Arch Dis Child 2005;90(2):187-189. View article
  11. National Institute for Health and Care Excellence. Urinary tract infection in children: Diagnosis, treatment and long-term management. NICE: CG54, 2007. View guideline