“…The validity of the videofluoroscopy rests heavily on the assumption that swallowing behaviors seen while swallowing barium are representative of swallowing behaviors that occur with normal, nonbarium liquids and foods outside the assessment context. However, the addition of barium sulfate powder to a thin liquid alters taste (Ekberg et al, 2009; Nagy, Steele, & Pelletier, 2014a) and is also known to alter rheological characteristics such as density, shear thinning, and extensional viscosity (Cichero, Burey, Nicholson, Halley, & Tobin, 2011; Cichero et al, 2000; Ekberg et al, 2009; Frazier et al, 2016; Steele, van Lieshout, & Goff, 2003; Stuart & Motz, 2009). Furthermore, commercially available barium sulfate products commonly include other ingredients to aid suspension, limit foaming, and achieve desired degrees of mucosal coating.…”