You need the junction, Date, rider details and accident summary.. that is it
If this map highlights a particular road or junction (Kingsland Road, Upper thames St, Southampton Row, St Johns etc) then further investigation and research needs to be carried out on that junction.

of users, # HGV/Busses, # near misses and so on, with sufficient data you can then create a case to change the road layout or sign an alternative route for cyclists, there isn't enough people working on this so effort has to be concentrated.

@TSK - Good point well made, i have a list of all road deaths over the last three years and the best information is from internet forums, then local papers a week or so later. they often recieve little or no collumn space..
They should still be noted but marked as un-confirmed, if 40% of accidents were un-confirmed or un-reported then i'd me more concerned about the seriousness of cycle safety in the media.

We haven't even plotted any severe (non-fatal) accidents....