On the face of it, data from the first year of the National Highway Traffic Safety Administration's project to track the safety of advanced driver assistance systems look terrible for Tesla. Its electric vehicles were involved in 70% of the reported crashes involving Level 2 technologies, 60% of those resulting in serious injuries and nearly 85% of the fatal ones.

The data released early Wednesday were collected under the federal regulator’s Standing General Order issued last June, requiring automakers to report the most serious crashes that involved Level 2 ADAS, which need a human driver to remain fully engaged in the driving task. NHTSA is also tracking crashes involving fully automated vehicles — none of which are currently available to consumers.

There are five levels of automation under standards created by SAE International. Level 2 means two functions such as adaptive cruise and lane keeping are automated and still have a human driver in the loop at all times. Level 2 is an advanced driver assistance system, and has become increasingly common in new vehicles.

Tesla topped the ADAS list for all the wrong reasons: 273 reported crashes, three with serious injuries, and five deaths. Honda trailed far behind Tesla with 90 crashes and one fatality, while most other manufacturers reported just a handful. Nissan reported none at all.

So does that mean Tesla owners should trade in their Model 3 with Autopilot for a Nissan Leaf, and its own Level 2 ADAS, called ProPilot?

It’s a more complicated question than one might think. The way the Order is worded, the technologies that Tesla has deployed, and the sheer number of Tesla vehicles on the road mean that its vehicles may not be quite as dangerous as the numbers suggest.

For a start, there are more ADAS-equipped Teslas on the road (about 830,000) than vehicles from other manufacturers, although Nissan isn’t far off, with 560,000.

Tesla’s Autopilot can also be used on a variety of roads, unlike Nissan’s ProPilot and GM’s SuperCruise systems, which are limited to highways. Without knowing the number of miles driven with each ADAS system in operation, and where, it is impossible to compare their relative levels of safety — or how each might contrast with accident rates under full human control.