BACKGROUND About 50% of term and 80% of preterm babies develop jaundice, which usually appears 2 to 4 days after birth, and resolves spontaneously after 1 to 2 weeks. Jaundice is caused by bilirubin deposition in the skin. Most jaundice in newborn infants is a result of increased red cell breakdown and decreased bilirubin excretion. METHODS We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of different wavelengths of light in hospital phototherapy as treatment for unconjugated hyperbilirubinaemia in term and preterm infants? What are the effects of different intensities of light in hospital phototherapy as treatment for unconjugated hyperbilirubinaemia in term and preterm infants? What are the effects of different total doses of light in hospital phototherapy as treatment for unconjugated hyperbilirubinaemia in term and preterm infants? What are the effects of starting hospital phototherapy at different thresholds in term and preterm infants? We searched Medline, Embase, The Cochrane Library, and other important databases up to January 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). RESULTS Fourteen studies were included. We performed a GRADE evaluation of the quality of evidence for interventions. CONCLUSIONS In this systematic review we present information relating to the effectiveness and safety of different wavelengths, intensities, total doses, and threshold for commencement of the following intervention: hospital phototherapy.