Almufty HB, Abdulrahman IS, Merza MA Latent Tuberculosis Infection among Healthcare Workers in Duhok Province: From Screening to Prophylactic Treatment. Trop Med Infect Dis. 2019 May 23;4(2):85. doi: 10.3390/tropicalmed4020085.
Chen B, Gu H, Wang X, Wang F, Peng Y, Ge E, Upshur R, Dai R, Wei X, Jiang J Prevalence and determinants of latent tuberculosis infection among frontline tuberculosis healthcare workers in southeastern China: A multilevel analysis by individuals and health facilities. Int J Infect Dis. 2019 Feb;79:26-33. doi: 10.1016/j.ijid.2018.11.010. Epub 2018 Nov 22.
Costa JC, Silva R, Ferreira J, Nienhaus A Active tuberculosis among health care workers in Portugal. J Bras Pneumol. 2011 Sep-Oct;37(5):636-45. doi: 10.1590/s1806-37132011000500011. English, Portuguese.
Park Y, Kim SY, Kim JW, Park MS, Kim YS, Chang J, Kang YA Serial testing of healthcare workers for latent tuberculosis infection and long-term follow up for development of active tuberculosis. PLoS One. 2018 Sep 20;13(9):e0204035. doi: 10.1371/journal.pone.0204035. eCollection 2018.
Latent Tuberculosis in Healthcare Workers - the Reality of a Portuguese Tertiary Hospital
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.