Dedoncker J, Brunoni AR, Baeken C, Vanderhasselt MA A Systematic Review and Meta-Analysis of the Effects of Transcranial Direct Current Stimulation (tDCS) Over the Dorsolateral Prefrontal Cortex in Healthy and Neuropsychiatric Samples: Influence of Stimulation Parameters. Brain Stimul. 2016 Jul-Aug;9(4):501-17. doi: 10.1016/j.brs.2016.04.006. Epub 2016 Apr 12. Review.
Galli G, Vadillo MA, Sirota M, Feurra M, Medvedeva A A systematic review and meta-analysis of the effects of transcranial direct current stimulation (tDCS) on episodic memory. Brain Stimul. 2019 Mar - Apr;12(2):231-241. doi: 10.1016/j.brs.2018.11.008. Epub 2018 Nov 17.
Hill AT, Fitzgerald PB, Hoy KE Effects of Anodal Transcranial Direct Current Stimulation on Working Memory: A Systematic Review and Meta-Analysis of Findings From Healthy and Neuropsychiatric Populations. Brain Stimul. 2016 Mar-Apr;9(2):197-208. doi: 10.1016/j.brs.2015.10.006. Epub 2015 Oct 23. Review.
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Non-invasive Transcranial Direct Current Stimulation to Improve Cognitive Efficiency
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.
