[dan000892]

s/effect/association/g

The study established association not causality (as is also customary in initial studies).

[tester756]

why do people write regex in comments?

I see it from time to time and struggle to understand it

[erichdongubler]

It's a concise notation for a type of editing drawn from an old Unix program called `sed`, which is still around in Unix's descendants (i.e., Linux).

In this case, GP suggests that GGP replace "effect" with "association".

[kQq9oHeAz6wLLS]

Strangely they are using the global flag, even though there's only one instance to replace.