For reasons that remain largely unexplained, the incidence of celiac disease has increased more than fourfold in the past sixty years.
This study has revealed large and unexplained regional incidence differences, e.g. between East and Central Africa.
The former is characteristically associated with a more indolent clinical course and a more severe proximal colonic involvement with rectal sparing (60 70%) (Loftus et al., 2005) and there is an unexplained higher incidence of colorectal cancer (Shetty et al., 1999, Soetikno et al., 2002).
Oesophageal cancer, in particular adenocarcinomas, has shown a rapid and largely unexplained increase in incidence in the Western world.
Surveys show large unexplained variation in incidence of sedation at the end of life across countries and care settings and there are ethical concerns about the use, intentions, risks and significance of the practice in palliative care.
Officials in Wisconsin and North Dakota say that feeding assistants actually reduced the incidence of unexplained weight loss and dehydration among nursing home residents, perhaps because they didn't rush the patients through their meals but sat and socialized with them instead.
One in three "non-toxic" chemicals used in the manufacture of everyday items significantly affected the potency of sperm cells, which may account for the high incidence of unexplained infertility in the human population, the researchers said.
To test whether there is unexplained variation in a) incidence of diagnosed bacterial food poisoning; and b) notification of bacterial food poisoning between general practices.
In high-risk areas, cattle movements also play a role, but unidentified local-scale processes may account for up to 75% of unexplained variation in the incidence of cattle bTB [29].
The average incidence of unexplained infertility varies from 0%to37%37 % [ 3].
