The NHTSA Bike HVE report and Traffic Tech were published relating to the two city passing distance intervention study using the C3FT device.
Available in the NTL/ROSAP/Behavioral Safety Research Collection:
Evaluating High Visibility Enforcement of Bicycle Passing Laws – DOT HS 813 248
Evaluating High Visibility Enforcement of Bicycle Passing Laws, Traffic Tech, Technology Transfer Series – DOT HS 813 249
They are also available via the NHTSA.gov website: