The Cadillac SuperCruise outranked the Tesla Inc. Autopilot in an Oct. 4 Consumer Reports review of partially automated driving systems.

The report evaluated four systems: Cadillac SuperCruise, a division of General Motors Co., the Tesla Autopilot, the Nissan Motor Co. Ltd. ProPilot Assist and the Volvo Pilot Assist, a subsidiary of Geely Automobile Holdings Ltd.

Consumer Reports tested the self-driving systems on capability and performance, ease of use, clarity for when safe to use, keeping the driver engaged and unresponsive drivers. There were five rankings, from "worse" to "better."

Cadillac had the best ranking, followed by Tesla, Nissan and Volvo, according to the report.

Using a Cadillac CT6 to test the system, the report said SuperCruise had the highest rating of "clear when safe to use" and also scored well with keeping the driver engaged. Its capabilities were in the middle of the scoring system, while ease of use had a lower score.

Tesla's Models X, S and 3 were tested, scoring high in capability and performance but lower on keeping the driver engaged, and it was less clear when it was safe to use the system.

The system was also tested on a Nissan Leaf and an Infiniti QX50, which achieved lower rankings for capability and performance, ease of use and clear when safe to use. The system scored in the middle on keeping the driver engaged.

Tests on Volvo's XC40 and XC60 found the automated driving system had the lowest rankings for each category, except it scored in the middle for keeping the driver engaged.