Odeny TA, Bukusi EA, Cohen CR, Yuhas K, Camlin CS, McClelland RS Texting improves testing: a randomized trial of two-way SMS to increase postpartum prevention of mother-to-child transmission retention and infant HIV testing. AIDS. 2014 Sep 24;28(15):2307-12. doi: 10.1097/QAD.0000000000000409.
Odeny TA, Newman M, Bukusi EA, McClelland RS, Cohen CR, Camlin CS Developing content for a mHealth intervention to promote postpartum retention in prevention of mother-to-child HIV transmission programs and early infant diagnosis of HIV: a qualitative study. PLoS One. 2014 Sep 2;9(9):e106383. doi: 10.1371/journal.pone.0106383. eCollection 2014.
Texting to Improve Testing (TextIT): A Cluster Randomized Stepped Wedge Trial of Text Messaging to Improve Postpartum Retention in Care and Early Infant Diagnosis of HIV
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.