Blodgett J, Theou O, Kirkland S, Andreou P, Rockwood K The association between sedentary behaviour, moderate-vigorous physical activity and frailty in NHANES cohorts. Maturitas. 2015 Feb;80(2):187-91. doi: 10.1016/j.maturitas.2014.11.010. Epub 2014 Nov 2
Gale CR, Westbury L, Cooper C Social isolation and loneliness as risk factors for the progression of frailty: the English Longitudinal Study of Ageing. Age Ageing. 2018 May 1;47(3):392-397. doi: 10.1093/ageing/afx188.
Katzmarzyk PT, Church TS, Craig CL, Bouchard C Sitting time and mortality from all causes, cardiovascular disease, and cancer. Med Sci Sports Exerc. 2009 May;41(5):998-1005. doi: 10.1249/MSS.0b013e3181930355.
Owen N, Healy GN, Matthews CE, Dunstan DW Too much sitting: the population health science of sedentary behavior. Exerc Sport Sci Rev. 2010 Jul;38(3):105-13. doi: 10.1097/JES.0b013e3181e373a2.
Petrusevski C, Choo S, Wilson M, MacDermid J, Richardson J Interventions to address sedentary behaviour for older adults: a scoping review. Disabil Rehabil. 2021 Oct;43(21):3090-3101. doi: 10.1080/09638288.2020.1725156. Epub 2020 Feb 14.
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.