Interesting article: Record linkage research and informed consent: who consents? Nicole Huang , Shu-Fang Shih, Hsing-Yi Chang and Yiing-Jenq Chou. BMC Health Services Research 2007, 7:18 doi:10.1186/1472-6963-7-18. [Abstract] [PDF] Description: Asking patients for permission before linking their data in a survey with health insurance records may be required from an ethical perspective, but it is well known to cause problems with selection bias. Those who agree to the linkage are different than those who refuse. In this study, researchers showed that age, income, literacy level, and other factors were different between patients who provided consent and those who did not provide consent. The description of this article was written on 2007-07-26, 2008-01-12. Category: Exclusions in research, Category: Interesting articles