> Lastly, we analyzed the use of blue-light filters, according to an answer to a simple question: whether participants did or did not use a specific filter for filtering blue-light on their screens. Only 10.6% of the sample (N1⁄474) reported using filters, whereas 622 parti- cipants did not. The most prevalent means of filtering blue light were f.lux (Windows) and Twilight (Android) software. No significant dif- ferences were observed for all sleep-related variables mentioned in the previous analyses. A statistical trend was found for the duration of sleep on workdays (489 vs. 461 minutes, t1⁄43.595, p1⁄40.058, Cohen's d1⁄40.23), meaning those that used blue-light filters slept in average approximately 28 minutes longer on a workday than those that did not use any means of filtering blue-light. No other differences were observed. An interesting finding, however, is that the group of people who use filters had more (albeit without statistical signifi- cance) total screen exposure (8.6 vs. 8.3 hrs) on average and more screen exposure on PC (4.3 vs. 3.6 hrs) and mobile devices (3.6 vs 3.4hrs), but less exposure to TV (0.7 vs. 1.2 hrs).
The article is quite positive about blue lights and presents excuses for its findings in the discussion. They ask for a better study with more participants and more samples.
(I don't have access to the article text and the abstract just seems to point the correlation)