TY  - RPRT
TI  - Effectiveness research and implications for study design: sample size and statistical power.
AU  - R Sturm
AU  - J Unützer
AU  - W Katon
DO  - 10.1016/s0163-8343(99)00024-9
UR  - https://pubmed.ncbi.nlm.nih.gov/10514951/
ID  - 10514951
ER  -