Lindsay Mitchell, whose history strongly suggests she is not for sale to any lobby group, has an impressive CV as a welfare commentator and researcher.
More importantly, her conclusions on this occasion do not apply solely to this country.
The indisputable fact that children who grow up in step, blended or sole-parent families are in greater danger of abuse by adults than those who grow up with both biological parents is replicated elsewhere.
Some hackles will be raised by her finding that Maori and Pacific families are over-represented in child abuse rates, and feature more than their share of ex-nuptial births, the absence of one parent or both, large numbers of siblings (especially from clustered or multiple births) and/or very young mothers. Long-term welfare dependence is another risk factor.
But, before the knives come out, she also finds that Maori and non-Maori children alike who live in two-parent working families suffer very low abuse rates.
Asian children, whose population has the lowest proportion of single-parent families, suffer disproportionately low rates of abuse.
The presence of biological fathers matters, she says, in protecting children from abuse, and marriage presents the greatest likelihood that the father will remain part of an intact family.
Mitchell's final conclusion is that there are "certain" family structures in which children will be far more vulnerable than others.
Is anyone surprised by that? Well yes, apparently some are. And offended. Some see it as a shameless plug for Family First, and the espousing of values that have had their day.
The world has changed, you see. Adults now have the right to scratch their itches. If they don't want to commit to a relationship, they don't have to.
Society no longer expects a public display of commitment, and like it or not, some children are paying a very high price for that.
It was very gracious of one critic to "strongly suggest" that the key is stability as opposed to marital status. But having made that concession, it is difficult to see how the remainder of her scepticism can be maintained.
Indeed, if the word 'marriage' was removed she would have no grounds for complaint at all.
Just why marriage should be the subject of such scorn is something of a mystery. It's not the ceremony itself that's important.
It doesn't have to involve priests and bridesmaids, the exchanging of vows or belief that God is watching.
It's the commitment between two people that matters, the public declaration that they have become a couple.
And like it or not, we don't need to be told that two biological parents will generally provide a safer environment for children than one biological parent and a stranger.
This research, with no disrespect whatsoever to Lindsay Mitchell, might be stating the bleeding obvious, but it's important for a number of reasons, not least the conclusion that the damage is being done not by colonisation or unemployment (and by extension poverty?) The real villain, what Family First says is the elephant in the room, is the demise of the nuclear family.
Given that marriage provides the bedrock of the nuclear family, it is not helpful to dismiss it as an archaic institution that has properly been succeeded by the right of the individual to behave as they like.
Once children enter the picture everything changes.
The prime focus of every parent should be on their children, and providing the best possible environment for raising them. That is often no longer the case in this country.
The rights of adults to live as they wish has superseded parental obligations.
To read Mitchell's research as a 'plug' for a lobby group that espouses traditional family values is foolish, and disheartening.
It proves exactly what McCoskrie says, that family structure is the elephant that some people simply will not see. Commitment to a relationship by whatever means - if anyone has a better word than marriage let's hear it - is what matters, and its absence is irrefutably linked to the abuse for which everyone in this country professes abhorrence but few seem willing to address in a meaningful way.
Years ago research was published claiming that children who attended kindergarten did not go to jail.
This was presented as an argument for pre-school education, and kindergarten in particular.
Obviously, however, kindergarten per se did not offer some magical recipe that all but eliminated the potential for future criminal behaviour. It was the way kindergarten worked that was the key.
Kindy was never parent-friendly. It operated in sessions, mornings for older children, afternoons for 3-year-olds.
Parents were required to deliver their children at a specific time, and to collect them again at the end of the session, and not a minute later.
Ferrying children to and fro wasn't always easy, but the rewards for the children, and parents, made it well worthwhile.
The fact that a child attended kindergarten indicated commitment.
The same parents no doubt subsequently ferried the same children to Saturday sport and after-school activities. They took a keen interest in their children's education and social development.
The fact that a child went to kindy demonstrated that their parents cared about them and were prepared to make an effort to give them the best opportunities in life.
The same argument applies to marriage. The point is that two people have presented themselves to a priest, court registrar or celebrant to publicly declare their commitment to each other, and in so doing have laid the best possible foundation for raising a family.
Rant against that all you like, but the facts speak for themselves. Mitchell finds that co-habiting parents are four to five times more likely than their married counterparts to part ways before their child is 5.
And while those data were replicated in other countries, New Zealand remained reluctant to identify which families were disproportionately associated with child abuse and deaths.
The fundamental problem is political correctness, and until we get over that, and start putting the rights of children ahead of those of their parents, nothing is going to change.
Not all marriages last, of course, and by no means are all unmarried parents bad parents.
But marriage has always underpinned the most successful form of family structure, and always will.
To borrow from Winston Churchill, who said democracy was the worst form of government, except for all the other forms that had been tried from time to time, it might be said that marriage provides the worst environment for the raising of children, except for all the other options.
