TY  - JOUR
T1  - CLinical practice guidelines and scientific evidence
AU  - McAlister FA
Y1  - 2009/07/08
N1  - 10.1001/jama.2009.909
JO  - JAMA
SP  - 142
EP  - 147
VL  - 302
IS  - 2
N2  - 
To the Editor: In their study, Dr Tricoci and colleagues1 pointed out that less than one-fifth of recommendations advocating a particular procedure or treatment in ACC/AHA practice guidelines were based on level A evidence. However, in using the ACC/AHA evidence grading schema to judge the quality of evidence underpinning guideline recommendations, I believe they have overestimated the strength of this evidence base. For example, under the ACC/AHA schema RCTs or meta-analyses are deemed to be level A evidence (or at worst level B if there is only a single RCT or the RCTs are small) irrespective of study conduct, end points evaluated (surrogate outcomes vs patient-centered outcomes), or the applicability of that RCT to the clinical scenario for which the recommendation is being made.

SN  - 0098-7484
M3  - doi: 10.1001/jama.2009.909
UR  - http://dx.doi.org/10.1001/jama.2009.909
ER  -