The following links will hopefully help define how stringent studies are done. The first link is from the US Preventitive Services Task Force (USPSTF) This is the manual for determining how studies are to be classed, how they are to be documented, and how the data is to be assessed.www.uspreventiveservicestaskforce.org/uspstf08/methods/procmanual4.htm
The following document is a simplified descript
ion as applied to prostate cancer from the PCRI:www.prostate-cancer.org/pcricms/sites/default/files/PDFs/ls12-3_p6-7.pdf
We see a lot of studies posted here. And most are not proof of anything. In fact, most are level II-2 or lower assessments.
Here is the rating system (Section 4.3 of the USPSTF manual):
The Task Force recognizes that research design is an important component of the validity of the information in a study, for the purpose of answering a key question. Although RCTs cannot answer all key questions, they are ideal for questions of the benefits or harms of various interventions. Thus, for these questions, the current Task Force endorses a slightly revised version of the "hierarchy of research design" used by the second Task Force:
The various Levels of data:
I: Properly powered and conducted randomized controlled trial (RCT); well-conducted systematic review or meta-analysis of homogeneous RCTs
II-1: Well-designed controlled trial without randomization
II-2: Well-designed cohort or case-control analytic study
II-3: Multiple time series with or without the intervention; dramatic results from uncontrolled experiments
III: Opinions of respected authorities, based on clinical experience; descript
ive studies or case reports; reports of expert committees
Level 1 data is very strict and is considered "proof" and anything below it is varied levels of evidence. Most local therapies lack Level I assessment. For example, the MSK nomograms are based on Level II-2 information.
I hope this helps putting studies into perspective.
Advanced Prostate Cancer at age 44 (I am 48 now)
pT3b,N0,Mx (original PSA was 19.8) EPE, PM, SVI. Gleason 4+3=7
RALP ~ 2/17/2007 at the City of Hope near Los Angeles.
Adjuvant Radiation Therapy ~ IMRT Completed 8/07
Adjuvant Hormone Therapy ~ 28 months on Casodex and Lupron.
"I beat up this disease and took its lunch money! I am in remission."
I am currently not being treated, but I do have regular oncology visits.
I am the president of an UsTOO chapter in Las Vegas
Blog : www.caringbridge.org/visit/tonycrispino