Study: Being part of an accelerator doesn’t help startups survice

I thought this study was really interesting. I came across it via the Sifted newsletter.

The author classifies startups in five ways:

1. Exits: are flagged as exited by Crunchbase
2. Scale-ups: flagged as alive on Crunchbase and 50 or more full-time employees on LinkedIn
3. Somewhat alive: flagged as alive on Crunchbase and between ten and 49 full-time employees on Linkedin
4. Zombies: flagged as alive on Crunchbase and less than ten full-time employees on LinkedIn
5. Dead: flagged as dead on Crunchbase or flagged as alive on Crunchbase, but no operational website or LinkedIn page and no full-time employees on LinkedIn

He looks at the common "1/10 startups survive" figure but focuses in on European startups. He finds a similar number (11%).

But, most interesting to me was the fact that the success rate for startups that go through accelerators (thereby giving up equity) was just 12%. And if you go through a corporate accelerator that drops to 8%.

Curious to hear your thoughts on this. Are accelerators a scam?