TY  - RPRT
TI  - Tutorial in biostatistics. An introduction to hierarchical linear modelling.
AU  - L M Sullivan
AU  - K A Dukes
AU  - E Losina
PY  - 1999
DO  - 10.1002/(sici)1097-0258(19990415)18:7<855::aid-sim117>3.0.co;2-7
UR  - https://pubmed.ncbi.nlm.nih.gov/10327531/
ID  - 10327531
ER  -