Adams V, Mathisen B, Baines S, Lazarus C, Callister R A systematic review and meta-analysis of measurements of tongue and hand strength and endurance using the Iowa Oral Performance Instrument (IOPI). Dysphagia. 2013 Sep;28(3):350-69. doi: 10.1007/s00455-013-9451-3. Epub 2013 Mar 7. Review.
Alsanei, W A. S. (2015). Tongue Pressure-A Key Limiting Aspect in Bolus Swallowing (Doctoral dissertation, University of Leeds).
Crow HC, Ship JA Tongue strength and endurance in different aged individuals. J Gerontol A Biol Sci Med Sci. 1996 Sep;51(5):M247-50.
Logemann, J A. (1998). Evaluation and Treatment of Swallowing Disorders (2nd ed.). Austin, TX: Pro-Ed.
Park JS, You SJ, Kim JY, Yeo SG, Lee JH Differences in orofacial muscle strength according to age and sex in East Asian healthy adults. Am J Phys Med Rehabil. 2015 Sep;94(9):677-86. doi: 10.1097/PHM.0000000000000230.
Robinovitch SN, Hershler C, Romilly DP A tongue force measurement system for the assessment of oral-phase swallowing disorders. Arch Phys Med Rehabil. 1991 Jan;72(1):38-42.
Stierwalt JA, Youmans SR Tongue measures in individuals with normal and impaired swallowing. Am J Speech Lang Pathol. 2007 May;16(2):148-56.
Vanderwegen J, Guns C, Van Nuffelen G, Elen R, De Bodt M The influence of age, sex, bulb position, visual feedback, and the order of testing on maximum anterior and posterior tongue strength and endurance in healthy belgian adults. Dysphagia. 2013 Jun;28(2):159-66. doi: 10.1007/s00455-012-9425-x. Epub 2012 Sep 16.
Vitorino J Effect of age on tongue strength and endurance scores of healthy Portuguese speakers. Int J Speech Lang Pathol. 2010 Jun;12(3):237-43. doi: 10.3109/17549501003746160.
Youmans SR, Youmans GL, Stierwalt JA Differences in tongue strength across age and gender: is there a diminished strength reserve? Dysphagia. 2009 Mar;24(1):57-65. doi: 10.1007/s00455-008-9171-2. Epub 2008 Aug 9.
The Influence of Age and Gender on Tongue Pressure and Swallowing Tongue Pressure
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.