“…For example, the age categories are not homogenous. In particular, the highest age category varies significantly by study: from 75 years (Dias et al ., 1994), to 80 years (Schrag et al ., 2000), to 90 years (Tison et al ., 1994; Claveria et al ., 2002), and to 95 years (van de Vijver et al ., 2001). Several surveys found an increasing tendency with age (Sutcliffe et al ., 1985, Granieri et al ., 1991; de Rijk et al ., 1995; Schrag et al ., 2000; van de Vijver et al ., 2001; Claveria et al ., 2002), while others reported a peak at the age of 70 (or 75) to 79 years (D'Alessandro et al ., 1987; Kis et al ., 2002), followed by a decreased prevalence at ages over 80 years.…”