1 Understand that hepatitis B vaccination-induced protective antibodies can last for up to 15 years, but appear to fall off over time.  Patients who were vaccinated 10 to 15 years ago, especially those who were vaccinated as children, may not be adequately protected. For patients with this history who are at moderate to high risk of hepatitis B infection consider quantitative hepatitis B antibody measurement to determine protective immunity.
Definition of thickness. 1 : the smallest of three dimensions length, width, and thickness. 2 : the quality or state of being thick. 3a : viscous consistency boiled to the thickness of honeyb : the condition of being smoky, foul, or foggy. 4 : the thick part of something. 5 : concentration, density.
1. the linear extent or measurement of something from end to end, usually being the longest dimension or, for something fixed, the longest horizontal dimension. 2. the extent of something from beginning to end, measured in some more or less regular units or intervals: the book was 600 pages in length.