Wednesday, September 9, 2009

Another look-see at NIS-3, or what do all those damn numbers means anyway?

The Third National Incidence Study of Child Abuse and Neglect (also known as NIS-3), put out by the U.S. Department of Health and Human Services, is getting up there in years. Although it's offficially a teenager as of this month--it was first published in September 1996--NIS-4 has yet to appear as it is (apparently) still a work in progress.

According to NIS-3's less-than-modest Forward, "The NIS is the single most comprehensive source of information about the currrent incidence of child abuse and neglect in the United States. The NIS-3 findings are based on a nationally representative sample of over 5,600 professionals in 842 agencies serving 42 counties."

While there may be more be more recent research on child abuse and neglect, it's necessarily more limited in geography and scope compared to NIS-3. So NIS-3 is still a major player by sheer heft alone.

I often see NIS-3 quoted by various mother advocates and fathers rights people, though usually the data is only pulled from NIS-3's rather confusing and rambling executive summary which is readily available at the HHS website. More than once I've been tangled up in the convoluted syntax, and I see other people get lost in it too. The entire study, we are grimly told, is not available on-line and must be ordered through the mail.

Well, gentle readers, I must make a confession. As I am a secret wonk at heart, I ordered the damn thing and got it jammed (and I mean jammed) in my mailbox yesterday.

So what does it say? Oh, NIS-3 is just packed with grisly data on mean mommies and dastardly dads. Everybody has picked over the raw numerical data on child abuse perpetrators and their gender and relationship to the child and what it all presumably means when moms are the majority of caretakers (or assumed caretakers) in both married couple and single-parent households.

Frankly, it's not terribly clear what it all means, and that's why everybody quotes it (or distorts it) for their own purposes.

Interestingly enough, when you turn to the section on family characteristics, the NIS-3 starts to make sense, though most of that data is not in the executive summary. That's because they take all the raw numerical data and crunch it in a way that's meaningful, which is incidence rates per 1,000 children.

Okay, before the less mathematically gifted among us have conniption fits, this is not really that fancy or complicated. This kind of data adjustment is done all the time. To know that Green City had 147 deaths from lung cancer last year, while Orange City had 361 doesn't tell us anything useful about cancer concentrations or about which City has relatively sicker or healthier citizens. Unless we know the population of those cities and how many people die per year, and express those numbers in terms of lung cancer deaths per 100,00o or something similar, we can't make any valid comparisons. So if I can tell you that Orange City had 50 lung cancer deaths per 100,000 while Green City had 100, we're now onto something interesting for further research.

So let's revisit the old question of abusive fathers versus abusive mothers with this in mind.

Fathers rights people often remind us that married couple families do better than single-parent households in nearly every measure of child abuse and neglect, which on the face of it is true. I suppose the public policy implication is keep everybody married with a man in the house (how we will do this is never made entirely clear--outlaw divorce?), and child abuse will lessen.

This is basically a variation of the BMW fallacy, or confusing correlation with causation. Here's how it goes. BMW owners are nearly uniformly well-to-do successful professionals with six figure incomes who own their own homes. So--if somebody who's low-income manages to buy a BMW, will they be financially successful?

No, they will be broke. Saddled with more car than they can afford and with more financial troubles than ever.

So it is with marriage. People who are happily married tend to stay married and tend not to have families plagued with abuse, drug or alcohol issues, mental health problems, and other stuff like that. Married people who do have these problems in their relationships will tend to split up over time and form single parent households.

So the question is not comparing single parents with married households, but comparing the relative safety of father-headed households and mother-headed households, even though the numbers of these households are not the same. (And not because of the family courts. Most mother-headed families are that way by default, not by design or legal proceedings.) Hence, we convert the child abuse data from each type of household type into incident rates per 1,000 children.

So what do we have then? Let's start by taking a peek at maltreatment (i.e. abuse and neglect) under what's called the "harm standard." Under the "harm standard," children were considered to be maltreated only if they had already experienced harm from abuse or neglect. (The other standard is the "endangerment standard," which is children who experience abuse or neglect that puts them at risk of harm, combined with kids who are alreadly harmed by abuse or neglect.)


Let's start with overall maltreatment (abuse and neglect combined).

Children living with their only their mothers experienced maltreatment under the Harm Standard at a rate of 26.1 per 1,000 children.

Children living with only their dads? 36.6 per 1,000.

As NIS-3 notes, "This rate is more than two and one-third times higher than that of children in two-parent families."

Oops. So much for the theory that keeping a dad--any dad--in the family somehow confers protection from that nasty abusive mommy.


What about abuse as such?

Children living with only their moms: 10.5 per 1,000.
Children living with only their dads: 17.7 per 1,000.

Here's what NIS-3 says about that: "Children in father-only families had more than twice the risk of abuse as defined by the harm standard compared to children living in both-parent families. Their risk was more than one and two-thirds that of children in mother-only families, a marginal difference in this maltreatment category. Thus, the pattern in connection with abuse essentially reflects the higher risk of children who live with only their fathers."


Physical abuse is a subcategory under abuse.

Children living with only their moms: 6.4 per 1,000 children.
Children living with only their dads: 10.5 per 1,000 children.

Here's what NIS-3 states: "When specific types of abuse under the Harm Standard are examined, it is apparent that the findings described in the previous paragraph stem from the disproportionate incidence of physical abuse among children in father-only households....An estimated 10.5 per 1,000 children living with only their fathers were harmed by physical abuse in 1993, which is more than two and two-thirds higher than the incidence rate of 3.9 per 1,000 for children living with both their parents. Children in mother-only families were not statistically different from those in both-parent households in their risk of physical abuse under the Harm Standard."


Let's turn to neglect now.

Children living with only their moms: 16.7 per 1,000 children.
Children living with only their dads: 21.9 per 1,000 children.


Emotional neglect is one of the subcategories under neglect. What do the numbers say now? Frankly, I figured moms would get nailed on something as nebulous as emotional neglect, but I was wrong.

Children living with only their moms: 3.4 per 1,000 children.
Children living with only their fathers: 8.8 per 1,000 children.


How about severity of injury? The data was said to be statisically unreliable for Fatalities, so let's turn to Serious Injuries.

Children living with only their moms: 10.0 per 1,000 children.
Children living with only their dads: 14.0 per 1,000.

And Moderate Injuries?

Children living with only their moms: 14.7 per 1,000 children.
Children living with only their dads: 20.5 per 1,000.

I'm not sure if there's enough data geeks among you to go into maltreatment under the "endangerment standard" (see definition above), but I will go into it briefly anyway. Suffice it to say that the pattern is very much the same, except with bigger numbers.


All maltreatment (abuse and neglect) for children living with only their moms: 50.1 per 1,000 children.
For children living with only their dads: 65.6 per 1,000.


All abuse for children living with only their moms: 18.1 per 1,000 children.
For children living only with their dads: 31.0 per 1,000.


Physical abuse for children living with only their moms: 9.8 per 1,000 children.
For children living with only their dads: 16.5 per 1,000.

As NIS-3 concludes, "Similar to the pattern described above in relation to Harm standard physical abuse, children who live with only their fathers are at a marginally higher risk of physical abuse than those who live with two parents. (The father-only household is associated with two and one-third times greater risk.)"

So there you have it straight from the NIS-3 mouth.