PT  - JOURNAL ARTICLE
AU  - P Cummings
AU  - T D Koepsell
TI  - Statistical and design issues in studies of groups
AID  - 10.1136/ip.8.1.6
DP  - 2002 Mar 01
TA  - Injury Prevention
PG  - 6--7
VI  - 8
IP  - 1
4099  - http://injuryprevention.bmj.com/content/8/1/6.short
4100  - http://injuryprevention.bmj.com/content/8/1/6.full
SO  - Inj Prev2002 Mar 01; 8