Assertion: trichloroethylene's use | /r/CapableOf | introduce bias
Facets:
Source sentences:
text: results.20,21 The Bruning et al study29 improved upon several study design aspects of the Vamvakas et al study; however, hospital referral patterns in the region and the use of hospital-based controls may have introduced bias.
text: results.20,21 The Bruning et al study29 improved upon several study design aspects of the Vamvakas et al study; however, hospital referral patterns in the region and the use of hospital-based controls may have introduced bias.