Helpful, that says nothing of the happiness of marriages. Certain communities look down on divorce so much that people would rather stay in bad, abusive marriages than get divorced.
I have seen statistics that do show dating length does not necessarily corrolate to length of marriage. But those studies include those who live together before marriage* and do not concentrate on religious groups. I would be surprised if levels of divorce in MO communities was vastly different than in right wing communities. I have not seen any data though.
What I’ve heard (and haven’t seen statistics so take this for what its worth) is that often people are living together and feel their relationship start to break apart so they get married or have a child in an attempt to solidify their relationship, which does nothing to actually fix their problem.