Paediatrics Calculators

79 calculators & risk scores

Browse 79 Paediatrics clinical calculators and risk scores used in everyday UK practice. Every tool runs entirely in your browser — enter the values and get instant scoring, colour-coded interpretation bands and a link to the underlying guideline or publication. ClinCalc Pro is free, needs no sign-up, and is built for working clinicians.

These paediatrics tools span Neonatal, Paediatric Calculations, Paediatric Deterioration, Respiratory, Head Injury, Neurological Assessment and more.

APGAR Score

Assesses neonatal condition at 1 and 5 minutes of life and the response to resuscitation; it does not decide whether resuscitation is needed.
Paediatric Weight Estimation (APLS)

Estimates weight in children for drug dosing when actual weight unavailable. APLS formulas (6th edition, 2016).
Paediatric Maintenance Fluid (Holliday-Segar)

Calculates maintenance IV fluid rate using Holliday-Segar method. Output in ml/hr.
Paediatric Early Warning Score (PEWS)

Identifies deteriorating children in hospital using age-appropriate vital sign thresholds.
Westley Croup Score

Classifies croup severity to guide management (dexamethasone, nebulised adrenaline, PICU).
PECARN Paediatric Head Injury

Decision rule for CT head in children with head injury. Minimises radiation exposure. Two algorithms: < 2 years and ≥ 2 years.
Paediatric Dehydration Assessment (WHO)

WHO (2005) clinical assessment of dehydration in children with diarrhoea: condition, eyes, thirst and skin pinch. NICE CG84 uses the same signs to recognise clinical dehydration and shock.
Neonatal Jaundice Threshold (NICE)

Compares serum bilirubin with the NICE CG98 phototherapy and exchange transfusion thresholds for gestational age and age in hours.
Paediatric Glasgow Coma Scale

Age-modified GCS for children under 5 years, accounting for developmental verbal and motor responses.
Yale Observation Scale (YOS)

Six-item observational scale to identify seriously ill febrile children aged 3–36 months. Scores ≤10 suggest low risk of serious illness.
CATCH Rule — Paediatric Head CT

Canadian Assessment of Tomography for Childhood Head injury. Guides CT head in children 0–16 years with blunt minor head injury (GCS 13–15) and loss of consciousness, amnesia, disorientation, persistent vomiting or irritability.
PRAM — Paediatric Respiratory Assessment Measure

Validated 5-item score assessing severity of acute asthma exacerbations in children aged 2–17 years.
Schwartz Equation — Paediatric GFR

Estimates GFR in children and adolescents using serum creatinine and height (bedside Schwartz formula).
Ballard Maturational Assessment

New Ballard Score (Ballard 1991): 6 neuromuscular and 6 physical maturity signs; the total converts to an estimated gestational age of 20–44 weeks.
CHALICE Rule for Childhood Head Injury

Children's Head injury ALgorithm for the prediction of Important Clinical Events — identifies children requiring CT head after head injury. Any criterion = CT indicated.
CHEOPS — Children's Hospital of Eastern Ontario Pain Scale

Observational pain scale for children aged 1–7 years. Assesses 6 behavioural categories. Score 4–13; higher = more pain.
Paediatric Trauma Score (PTS)

Triage tool for paediatric trauma patients. Score -6 to +12. PTS ≤8 predicts major injury requiring paediatric trauma centre.
Step-by-Step Approach to Febrile Infants

Sequential rule for well and unwell febrile infants ≤ 90 days old with fever without source (Gomez 2016): appearance, age, urinalysis, procalcitonin, then CRP and neutrophil count, to identify infants at low risk of invasive bacterial infection (IBI).
Paediatric Early Warning Score (PEWS)

Structured observation-based scoring system to identify children at risk of clinical deterioration. Scores behaviour, cardiovascular, and respiratory domains. Triggers escalation based on total score.
Kawasaki Disease Diagnostic Criteria

Diagnoses Kawasaki disease (KD) using clinical criteria. Classic KD requires fever ≥5 days PLUS ≥4 of 5 principal features. Incomplete KD: fever ≥5 days with <4 features but echocardiographic or laboratory evidence.
Kocher Criteria for Septic Arthritis of the Hip

Differentiates septic arthritis from transient synovitis in children with acute hip pain. Each predictor increases the probability of septic arthritis multiplicatively.
Bacterial Meningitis Score for Children

Identifies children with CSF pleocytosis at low risk of bacterial meningitis who may not require empirical antibiotics. Score ≥2 or any high-risk feature = treat as bacterial.
Rochester Criteria for Febrile Infants

Identifies febrile infants ≤ 60 days old (rectal temperature ≥ 38 °C) at low risk of serious bacterial infection (SBI). All 7 criteria must be met for 'low risk'.
BRUE Criteria for Infants

Brief Resolved Unexplained Events (BRUE) criteria replace ALTE (apparent life-threatening event). Identifies lower-risk infants who may not need extensive workup.
Pediatric Appendicitis Score (PAS)

Samuel's Pediatric Appendicitis Score assesses risk of acute appendicitis in children. More sensitive for paediatric appendicitis than the Alvarado score in children.
Pediatric Asthma Severity Score (PASS)

Scores severity of acute asthma exacerbation in children aged 1–18 years. Guides treatment decisions and disposition (discharge vs hospital admission).
Pediatric Ulcerative Colitis Activity Index (PUCAI)

Non-invasive clinical score for disease activity in paediatric ulcerative colitis. Validated as an alternative to endoscopy in children. Remission: <10. Severe: ≥65.
PELD Score (Pediatric End-Stage Liver Disease)

Predicts mortality in children under 12 years old with end-stage liver disease. Used for liver transplant priority listing (similar to MELD for adults). Higher score = higher mortality risk.
Pediatric Crohn's Disease Activity Index (PCDAI)

Assesses disease activity in paediatric Crohn's disease (Hyams 1991). Turner 2010 cut-offs: remission < 10, mild 10–27.5, moderate 30–37.5, severe ≥ 40.
Lansky Play-Performance Scale

Measures functional performance in paediatric oncology patients aged 1–16 years. Analogous to the Karnofsky Performance Scale for children. 100 = fully active; 0 = unresponsive.
Shock Index, Pediatric Age-Adjusted (SIPA)

Age-adjusted Shock Index for paediatric patients. HR/SBP ratio with age-specific thresholds. Predicts need for blood transfusion, massive transfusion, and mortality in paediatric trauma.
Oxygenation Index (OI)

Measures severity of hypoxaemic respiratory failure in mechanically ventilated paediatric patients. OI >16 suggests severe respiratory failure; OI >40 indicates potential ECMO candidacy.
Phoenix Sepsis Score

2024 international paediatric sepsis criteria (Phoenix). Scores respiratory, cardiovascular, coagulation and neurological dysfunction; replaces the SIRS-based 2005 definitions. Missing measurements score 0.
Paradise Criteria for Tonsillectomy in Children

Identifies children who are most likely to benefit from tonsillectomy based on frequency and severity of sore throat episodes. Threshold: ≥7 episodes in 1 year, or ≥5/year for 2 years, or ≥3/year for 3 years.
FLACC Scale (Face, Legs, Activity, Cry, Consolability) for Pediatric Pain

Behavioural pain assessment tool for children 2 months to 7 years (and non-verbal patients) who cannot self-report pain. Validated for post-operative and procedural pain assessment.
Paediatric Endotracheal Tube (ETT) Size and Depth Calculator

Calculates appropriate uncuffed and cuffed ETT size, and insertion depth for children based on age. Based on validated age-based formulas used in APLS/EPLS guidelines.
Paediatric SIRS, Sepsis, and Septic Shock Criteria

Age-adjusted criteria for SIRS, sepsis, severe sepsis, and septic shock in children. Based on International Pediatric Sepsis Consensus Conference (IPSCC) 2005 definitions.
Cornell Assessment of Pediatric Delirium (CAPD)

Nursing-administered observational delirium screening tool for children in PICU. Validated for all ages including non-verbal and pre-verbal children. Score >= 9 indicates delirium.
HEADS-ED: Paediatric Mental Health Assessment for the Emergency Department

Standardised tool for assessing paediatric mental health presentations in the emergency department. Assesses 7 domains: Home, Education, Activities, Drugs/alcohol, Suicidality, Emotions/Behaviour, Discharge resources.
PECARN Paediatric Intra-Abdominal Injury (IAI) After Blunt Torso Trauma

Validated clinical decision rule to identify children at very low risk of intra-abdominal injury requiring acute intervention following blunt torso trauma, potentially avoiding CT scanning.
Adverse Childhood Experiences (ACE) Score

Retrospective questionnaire assessing 10 categories of adverse childhood experiences. Higher ACE scores correlate with increased risk of physical and mental health conditions in adulthood. Used in paediatric, family medicine, and public health settings.
Modified Asthma Predictive Index (mAPI) for Children

Identifies young children (≤ 3 years) with recurrent wheeze at high risk of persistent asthma at school age. Modified API (PEAK trial / COAST cohort) of the original Tucson Asthma Predictive Index.
Behavioural Observational Pain Scale (BOPS) for Post-Operative Paediatric Pain

Three-item observational pain scale for post-operative pain assessment in children aged 1-7 years. Validated in children unable to self-report pain. Uses facial expression, verbalisation, and body position.
Palchak (UC Davis) Rule for Paediatric Head Trauma CT Prediction

Clinical decision rule for CT head in children with blunt head trauma. Developed at UC Davis to identify children at low risk for traumatic brain injury without CT scanning.
DHAKA Score for Paediatric Dehydration Assessment

DHAKA Dehydration Score (Levine 2015) for children under 5 with acute diarrhoea: general appearance, respirations, skin pinch and tears (0–12). Derived and externally validated in Dhaka, Bangladesh.
Withdrawal Assessment Tool (WAT-1) for Paediatric Iatrogenic Withdrawal

Validated 11-item tool for assessing iatrogenic opioid and benzodiazepine withdrawal in critically ill children. Assesses symptoms over the past 12 hours plus a 2-minute observation period.
CKiD U25 eGFR Calculator for Children and Young Adults

Revised Schwartz CKiD U25 equation for estimating GFR in children and young adults aged 1-25 years using serum creatinine, cystatin C, BUN, height, and sex. More accurate than the bedside Schwartz equation.
Paediatric NEXUS II Head CT Decision Instrument for Blunt Trauma

The NEXUS II head CT decision instrument applied to children (Oman 2006). Of its 8 criteria, age 65 or over does not apply to children, leaving 7. All absent = low risk of clinically important intracranial injury.
CATCH Rule for Paediatric Head Injury

Canadian Assessment of Tomography for Childhood Head Injury (CATCH) rule. Identifies children at risk for brain injury requiring CT head after minor head injury.
Kocher Criteria for Septic Arthritis in Children

Predicts probability of septic arthritis of the hip in children, differentiating from transient synovitis. Used to guide need for emergency surgery.
Lansky Play-Performance Scale

Measures functional status and activity level in children (ages 1–16). Paediatric equivalent of the Karnofsky Performance Scale. Used in oncology and palliative care.
Pediatric Asthma Score (PAS)

Assesses asthma exacerbation severity in children aged 2–18 to guide treatment intensity and disposition.
Pediatric Appendicitis Score (PAS)

Estimates risk of appendicitis in children aged 3–18 presenting with abdominal pain. Aids in disposition and imaging decisions.
Oxygenation Index (OI)

Calculates the Oxygenation Index to quantify the severity of hypoxic respiratory failure in mechanically ventilated paediatric patients. Used to guide ECMO candidacy and PARDS severity classification.
Pediatric Glasgow Coma Scale (pGCS)

Modified Glasgow Coma Scale for infants and young children (<2 years), with age-appropriate verbal response scoring. Assesses level of consciousness and guides clinical decision-making.
Paediatric Early Warning Score (PEWS)

Standardised scoring tool to detect clinical deterioration in hospitalised children. Triggers escalation to senior review or PICU referral.
Paediatric Fluid Resuscitation Calculator

Calculates initial fluid resuscitation bolus and maintenance fluid rate for children based on weight. Uses Holliday-Segar formula for maintenance and weight-based bolus for resuscitation.
Paediatric INR Goals for Mechanical Heart Valves

Target INR ranges for anticoagulation in children with mechanical heart valves, based on valve position and type. Guides warfarin management in paediatric cardiology.
Bronchiolitis Severity Score (Wang Score)

Wang clinical severity score for bronchiolitis in infants. Guides clinical decision-making for bronchiolitis management and hospital admission.
Kawasaki Disease Diagnostic Criteria

American Heart Association (AHA) diagnostic criteria for Kawasaki Disease (KD). Fever ≥5 days PLUS ≥4 principal features required for classic KD. Guides IVIG and aspirin therapy.
Neonatal Jaundice Treatment Thresholds (NICE CG98)

Assesses risk of significant hyperbilirubinaemia in newborns using hour-specific total serum bilirubin (TSB) plotted on the Bhutani nomogram. Guides phototherapy and exchange transfusion decisions.
Paediatric Sepsis Criteria (pSOFA)

Paediatric Sequential Organ Failure Assessment (pSOFA). Adapted from adult SOFA; assesses organ dysfunction across 6 systems for paediatric sepsis severity and mortality prediction.
Revised Trauma Score (T-RTS) in Children

The triage Revised Trauma Score (coded GCS + systolic BP + respiratory rate) applied to injured children. There is no separate paediatric version; the Paediatric Trauma Score is the paediatric-specific alternative.
Paediatric Index of Mortality 3 (PIM3)

Predicts the risk of death for children (< 16 years in the original model; < 18 in PIM3) admitted to intensive care, from values in the first hour. Designed for benchmarking units, not for individual decisions.
Neonatal Abstinence Syndrome Score (Finnegan)

Scores severity of neonatal abstinence syndrome (NAS) in neonates exposed to opioids in utero. Guides pharmacotherapy initiation.
Paediatric Burn TBSA (Lund-Browder)

Estimates total body surface area (TBSA) burned in children using the Lund-Browder chart, which accounts for age-related proportions.
Tanner Staging (Sexual Maturity Rating)

Assesses pubertal development stage in children and adolescents based on physical characteristics.
Fenton Preterm Growth Chart (Gestational Age Correction)

Assesses growth of preterm infants using corrected gestational age. Identifies SGA (<10th percentile) and LGA (>90th percentile).
Denver Developmental Screening Test II (DDST-II)

Screens for developmental delays in children from birth to 6 years across four domains: personal-social, fine motor, language, gross motor.
Paediatric Glasgow Coma Scale (pGCS)

Modified GCS adapted for preverbal and young children. Assesses eye, verbal, and motor responses. Score 15 = normal; score ≤ 8 = severe impairment, secure airway.
Westley Croup Score

Assesses croup (laryngotracheobronchitis) severity in children (Westley 1978, 0–17). Guides corticosteroid, nebulised adrenaline and admission decisions.
Pediatric Asthma Severity Score (PASS)

Gorelick's Pediatric Asthma Severity Score for acute asthma in children aged 1–18: wheezing, work of breathing and prolongation of expiration, each 0–2 (total 0–6).
Febrile Seizure Risk Stratification

Classifies febrile seizures as simple vs complex and stratifies meningitis risk and recurrence. Guides LP decision and anticonvulsant use.
Kawasaki Disease Diagnostic Criteria

Diagnoses Kawasaki disease using AHA/JCS classic and incomplete criteria. Guides IVIG and aspirin therapy to prevent coronary artery aneurysms.
Paediatric DKA Severity Assessment (ISPAD)

Classifies paediatric DKA severity by the degree of acidosis (ISPAD 2022). Diagnosis also needs glucose > 11 mmol/L and ketonaemia (β-hydroxybutyrate ≥ 3 mmol/L) or moderate/large ketonuria. In the UK follow the BSPED guideline, whose severity bands differ.
RACHS-1 — Risk Adjustment for Congenital Heart Surgery

Six-category consensus risk adjustment for in-hospital mortality after congenital heart surgery in children (Jenkins 2002). Use the category of the most complex procedure. For comparing groups, not individual prognosis.
Phoenix Sepsis Score (Paediatric Sepsis Criteria)

International consensus criteria for sepsis and septic shock in children under 18 (SCCM Pediatric Sepsis Definition Task Force, 2024). Phoenix score = respiratory (0–3) + cardiovascular (0–6) + coagulation (0–2) + neurological (0–2). Sepsis = suspected infection with a score ≥ 2; septic shock = sepsis with ≥ 1 cardiovascular point. Replaces the 2005 IPSCC (SIRS-based) criteria.
PELOD-2 — Paediatric Logistic Organ Dysfunction Score

PELOD-2 (Leteurtre 2013): 10 variables across 5 organ dysfunctions (neurological, cardiovascular, renal, respiratory, haematological), score 0–33. Use the worst value of each variable over the period; a variable not measured is taken as normal.
CHAQ — Childhood Health Assessment Questionnaire

Childhood Health Assessment Questionnaire (Singh 1994) for juvenile idiopathic arthritis: 30 items in 8 domains rated 0 (without difficulty) to 3 (unable). Result = disability index, the mean of the 8 domain scores (0–3).