TY  - RPRT
TI  - Understanding controlled trials. Why are randomised controlled trials important?
AU  - B Sibbald
AU  - M Roland
PY  - 1998
DO  - 10.1136/bmj.316.7126.201
UR  - https://pubmed.ncbi.nlm.nih.gov/9468688/
ID  - 9468688
ER  -