DO NOT trust that study because
eHarmony is ONLY a 16+ years old obsolete site and a HOAX, based on a big scientific fraud, only sustained by big marketing budget.
The Big Five normative test used by eHarmony, had been proven/revealed as an incomplete and incorrect model to assess/measure personality of persons.
Moreover eHarmony was copycatted in several countries like the online dating sites EliteSingles in Canada, Australia, USA, UK; eDarling in Spain, German, France, Russia; also TeAmo in Russia is another copycat of eHarmony. eSynchrony in Singapore, MiMediaManzana in Colombia, Peru, Mexico, Chile, etc.
SFC article: eHarmony CEO wants to court the Tinder crowd
eHarmony reinforces security
Very easy to copycat eHarmony, but very difficult to innovate: a 100 times better algorithm than eHarmony.