SIDS is rare and probably has nothing to do with a baby's position.
There's a bunch of research on the subject, and the resulting recommendation is that sleeping on the back is preferred. I haven't read the actual studies, but a bunch are mentioned in the article I linked to:
Swedish Medical Research Council State of the Art Conference on the Sudden Infant Death Syndrome. Proceedings. Gothenburg, 3-5 June 1992. Acta Paediatr Suppl 1993;389(1):1-129.
Alm B, Milerad J, Wennergren G, Skjaerven R, Øyen N, Norvenius G, et al. A case-control study of smoking and sudden infant death syndrome in the Scandinavian countries, 1992 to 1995. The Nordic Epidemiological SIDS Study. Arch Dis Child 1998;78(4):329-34.
Alm B, Norvenius SG, Wennergren G, Skjaerven R, Oyen N, Milerad J, et al. Changes in the epidemiology of sudden infant death syndrome in Sweden 1973-1996. Arch Dis Child 2001;84(1):24-30.
Alm B, Möllborg P, Erdes L, Pettersson R, Aberg N, Norvenius G, Wennergren G. SIDS risk factors and factors associated with prone sleeping in Sweden. Arch Dis Child. 2006;91:915-9.
Wennergren G. Prevention of sudden infant death syndrome. Pediatr Pulmonol 2004;37 Suppl 26:110-1.
Carpenter RG, Irgens LM, Blair PS, England PD, Fleming P, Huber J, et al. Sudden unexplained infant death in 20 regions in Europe: case control study. Lancet 2004;363(9404):185-91.
American Academy of Pediatrics, Task Force on Sudden Infant Death Syndrome. Policy Statement. The changing concept of sudden infant death syndrome: diagnostic coding shifts, controversies regarding the sleeping environment, and new variables to consider in reducing risk. Pediatrics 2005;116:1245-55.
[edit: google the names of the studies and you'll find abstracts or more]
I've read some of the actual studies you've quoted (and others), and they seem to indicate that infants that sleep on their backs fair slightly better in statistics. Some also blame heavier blankets and "bumper pads" (the pads that wrap around the bars at the base of the mattress).
As I mentioned elsewhere, my understanding is that it's merely a recommendation based on statistics with no direct correlation.
My babies went on their backs, because even a %.001 difference is enough for me to play the game, seeing as I don't know what I'd do if one of them passed away.
a recommendation based on statistics with no direct correlation
"a recommendation based on statistics" usually means there is a correlation. I think you mean that it may not imply causation, which is true of course.
There's a bunch of research on the subject, and the resulting recommendation is that sleeping on the back is preferred. I haven't read the actual studies, but a bunch are mentioned in the article I linked to:
Alm B, Lagercrantz H, Wennergren G. Stop SIDS - sleeping solitary supine, sucking soother, stopping smoking substitutes. Acta Paediatr. 2006 Mar;95(3):260-2.
Swedish Medical Research Council State of the Art Conference on the Sudden Infant Death Syndrome. Proceedings. Gothenburg, 3-5 June 1992. Acta Paediatr Suppl 1993;389(1):1-129.
Alm B, Milerad J, Wennergren G, Skjaerven R, Øyen N, Norvenius G, et al. A case-control study of smoking and sudden infant death syndrome in the Scandinavian countries, 1992 to 1995. The Nordic Epidemiological SIDS Study. Arch Dis Child 1998;78(4):329-34.
Alm B, Norvenius SG, Wennergren G, Skjaerven R, Oyen N, Milerad J, et al. Changes in the epidemiology of sudden infant death syndrome in Sweden 1973-1996. Arch Dis Child 2001;84(1):24-30.
Alm B, Möllborg P, Erdes L, Pettersson R, Aberg N, Norvenius G, Wennergren G. SIDS risk factors and factors associated with prone sleeping in Sweden. Arch Dis Child. 2006;91:915-9.
Wennergren G. Prevention of sudden infant death syndrome. Pediatr Pulmonol 2004;37 Suppl 26:110-1.
Carpenter RG, Irgens LM, Blair PS, England PD, Fleming P, Huber J, et al. Sudden unexplained infant death in 20 regions in Europe: case control study. Lancet 2004;363(9404):185-91.
American Academy of Pediatrics, Task Force on Sudden Infant Death Syndrome. Policy Statement. The changing concept of sudden infant death syndrome: diagnostic coding shifts, controversies regarding the sleeping environment, and new variables to consider in reducing risk. Pediatrics 2005;116:1245-55.
[edit: google the names of the studies and you'll find abstracts or more]