One of the least-studied pieces of the gun violence puzzle is how many households own a firearm in each state. There are reasonable estimates at the national and regional levels, but not beyond that.

In a recent interview, Rep. Tom Cole, R-Okla., took a stab at putting a number on ownership in his state. He was talking about being at ease among people with conceal carry permits.

"Probably one out of every two households in Oklahoma has a gun," Cole said on MSNBC’s Morning Joe Feb. 28. "I move in that world every day."

We asked Cole’s staff where he got that ballpark figure and didn’t hear back.

There is a federal government survey from 2004 that asked people, "Are any firearms now kept in or around your home?" In Oklahoma, 42.9 percent said yes. Nationally, the figure was 31.7 percent.

A 2015 article in a peer-reviewed journal, based on a 2013 poll, said that 31.2 percent of Oklahomans reported that they owned a firearm. However, the lead author of the study distanced herself from such a precise estimate.

"Considering that our sample size was modest, please exercise caution," said Bindu Kalesan, assistant professor of Medicine and Community Health Science at Boston University.

The study was about social gun culture nationally, and "everything else is secondary or exploratory," Kalesan said.

Kalesan said so far as she knows, no study has looked at household gun ownership at the state level.

The General Social Survey conducted by NORC at the University of Chicago found that in 2014, 43 percent of people in the West South Central region, which includes Oklahoma, Texas, Louisiana and Arkansas, said there was some sort of firearm in their home.

Nationally, 31 percent reported the presence of a gun in the home.

Our ruling

Cole said half the households in Oklahoma have a gun. In reality, there’s no fresh and reliable data for household gun ownership in the state. A survey from nearly 15 years ago reported that 42 percent of Oklahomans said there was a firearm in their house. A 2014 survey gave an ownership rate of 43 percent of households within a cluster of four states that included Oklahoma.

Both the old and the more recent surveys estimated a national ownership rate of about 31 percent. While we can’t say for sure that the older study still holds true for Oklahoma proper, based on its national numbers, it is at least in the same neighborhood as the more recent regional and national estimates.

Cole’s figure seems a bit high, but there’s a reasonable chance that the actual number is close to 40 percent.

Better data is always a good thing, but we’ll give Cole the benefit of the doubt and rate this Mostly True.