Dinlen N, Zenciroglu A, Beken S, Dursun A, Dilli D, Okumus N Association of vitamin D deficiency with acute lower respiratory tract infections in newborns. J Matern Fetal Neonatal Med. 2016 Mar;29(6):928-32. doi: 10.3109/14767058.2015.1023710. Epub 2015 Mar 19.
Fort P, Salas AA, Nicola T, Craig CM, Carlo WA, Ambalavanan N A Comparison of 3 Vitamin D Dosing Regimens in Extremely Preterm Infants: A Randomized Controlled Trial. J Pediatr. 2016 Jul;174:132-138.e1. doi: 10.1016/j.jpeds.2016.03.028. Epub 2016 Apr 11.
Gernand AD, Simhan HN, Caritis S, Bodnar LM Maternal vitamin D status and small-for-gestational-age offspring in women at high risk for preeclampsia. Obstet Gynecol. 2014 Jan;123(1):40-48. doi: 10.1097/AOG.0000000000000049.
Hollis BW, Johnson D, Hulsey TC, Ebeling M, Wagner CL Vitamin D supplementation during pregnancy: double-blind, randomized clinical trial of safety and effectiveness. J Bone Miner Res. 2011 Oct;26(10):2341-57. doi: 10.1002/jbmr.463. Erratum in: J Bone Miner Res. 2011 Dec; 26(12):3001.
Monangi N, Slaughter JL, Dawodu A, Smith C, Akinbi HT Vitamin D status of early preterm infants and the effects of vitamin D intake during hospital stay. Arch Dis Child Fetal Neonatal Ed. 2014 Mar;99(2):F166-8. doi: 10.1136/archdischild-2013-303999. Epub 2013 Jul 13.
Nemet D, Dolfin T, Wolach B, Eliakim A Quantitative ultrasound measurements of bone speed of sound in premature infants. Eur J Pediatr. 2001 Dec;160(12):736-40.
Pinto K, Collins CT, Gibson RA, Andersen CC Vitamin D in preterm infants: A prospective observational study. J Paediatr Child Health. 2015 Jul;51(7):679-81. doi: 10.1111/jpc.12847. Epub 2015 Feb 12.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.