PT  - JOURNAL ARTICLE
AU  - Bilimoria, Karl Y
AU  - Chung, Jeanette W
AU  - Hedges, Larry V
TI  - External validity is also an ethical consideration in cluster-randomised trials of policy changes
AID  - 10.1136/bmjqs-2018-008777
DP  - 2019 Feb 01
TA  - BMJ Quality & Safety
PG  - 167--167
VI  - 28
IP  - 2
4099  - http://qualitysafety.bmj.com/content/28/2/167.short
4100  - http://qualitysafety.bmj.com/content/28/2/167.full
SO  - BMJ Qual Saf2019 Feb 01; 28