Same Sex Marriage "Study?"

[From article]
Researchers at the Open University in the United Kingdom interviewed and surveyed over 5,000 people and found that men and women without children are more satisfied with their relationships; they are also more likely to feel valued by their partner. The participants included people of all ages, statuses, and sexual orientation.

What is the definition of happiness? How is it measured? Is this an effort to promote same sex marriage using the prestige of an university? Did they establish a rational standard for what happiness is? It is curious that philosophers are unable to define happiness in a way that is easily measured. Rush Limbaugh raised the question whether this study is an effort to promote and celebrate same sex marriage. Do the cultural warriors make use of an alleged academic study to be quoted in media? 

http://atlanta.cbslocal.com/2014/01/14/study-couples-without-children-have-happier-marriages/

Study: Couples Without Children Have Happier Marriages
January 14, 2014 12:37 AM