Patient description: A 3-day-old Asian female infant presents with jaundice that started a day ago. She was born at 38w3d of gestation, after an uncomplicated pregnancy. The family history is unremarkable. The baby is breastfed. Vital signs are reported as: axillary temperature: 36.3°C, heart rate: 154 beats/min, respiratory rate: 37 breaths/min, and blood pressure: 65/33 mm Hg. Her weight is 3.2 kg, length is 53 cm, and head circumference 36 cm. Her sclera are yellow and her body is icteric. No murmurs or any other abnormalities are detected in the heart and lung auscultation. Her liver and spleen are normal on palpation. Laboratory results are as follows: Serum total bilirubin: 21.02 mg/dL Direct bilirubin of 2.04 mg/dL AST: 37 U/L ALT: 20 U/L GGT: 745 U/L Alkaline phosphatase: 531 U/L Creatinine: 0.3 mg/dL Urea: 29 mg/dL Na: 147 mEq/L K: 4.5 mEq/L CRP: 3 mg/L Complete blood cell count within the normal range. She is diagnosed with uncomplicated neonatal jaundice that may require phototherapy.

Clinical trial eligibility criteria: eligible ages (years): 0.0-4.917,  Pneumonia Childhood for child in accuracy and consistency evaluations for ARIDA test device and expert clinician: A child (2 to 59 months) who fulfils ALL of the following will be included in the accuracy and consistency evaluations: 1. Age 2 to 59 months 2. Cough or difficulty breathing 3. Parent or Guardian consent A young infant (0 to <2 months) who fulfils ALL of the following will be included in the accuracy evaluation: 1. Age 0 to <2 months 2. Parent or Guardian consent for child in RR fluctuation evaluations: A child who fulfils ALL of the following will be included in the respiratory rate fluctuation evaluation: 1. Age 2 to 59 months 2. Parent or Guardian consent 3. Normal breathing  for child/young infant in all elements of the study: A child/young infant with the following will be excluded from all elements of this study: 1. General danger signs: 1. Newborns (<28 days): not feeding well, active convulsions/fits, chest indrawing, fever (37.5 degrees or more), low body temperature (less than 35.5 degrees) or movement only when stimulated/no movement at all. 2. All other age groups: active convulsions/fits, unconscious/lethargic, not breastfeeding/not drinking or vomiting everything. 2. Signs of severe pneumonia: 1. Chest indrawing or 2. Stridor in a calm child 3. IMNCI pink referral signs for severe disease including stridor, severe dehydration, severe persistent diarrhoea, very severe febrile disease, severe complicated measles, mastoiditis, complicated severe malnutrition, and severe anaemia. 4. Parent or Guardian's age less than 16 years. 5. No Parent or Guardian consent. 7. Device Manufacturer Safety If newborn or young infant (<2months): 1. Born before 37 weeks of gestation (pre-term) All age groups: 2. Wearing supportive device at area of chest/belly 3. Skin not intact in chest/belly In addition, a child with the following will be excluded from the respiratory rate fluctuation evaluation: 1. Cough or difficult breathing 2. Fast breathing (see table 2) Additional for child/young infant in an in-patient facility: 1. Child/young infant being managed by barrier nursing (such as severe burns, child with neutropenia, severe infectious diseases). 2. Child/young infant not eligible for research procedures as advised by the supervising clinician