Narrow band green light effects on headache, photophobia, sleep, and anxiety among migraine patients: an open-label study conducted online using daily headache diary.
Although not significantly different, a nonsignificant trend was observed ( p = 0.083, Mann Whitney).
also in 5,406 other papers
Quoted from the open-access full text in Europe PMC under the licence the publisher applied. The sentence is reproduced exactly as published; the emphasis is ours.