You might also check my previous notes [in fact I may do so myself to ensure there are no holes...]
http://www.alzheimers.org.uk/talkingpoint/discuss/showthread.php?t=2879
Below, page 1 of the new notes
http://www.alzheimers.org.uk/talkingpoint/discuss/showthread.php?t=2879
Below, page 1 of the new notes