TY  - RPRT
TI  - Data-based approach for developing a physical activity frequency questionnaire.
AU  - M Bernstein
AU  - D Sloutskis
AU  - S Kumanyika
AU  - A Sparti
AU  - Y Schutz
AU  - A Morabia
PY  - 1998
DO  - 10.1093/oxfordjournals.aje.a009427
UR  - https://pubmed.ncbi.nlm.nih.gov/9457004/
ID  - 9457004
ER  -