Firearms mortality, either murder, accidental or suicide, has always been a public health issue in the USA. There have been several good epidemiological studies that have examined whether gun control regulations and firearms mortality risk are related – and the results are surprisingly vigorous.

From recent epidemiological research, there is some convincing evidence that establishes a correlation between state-level gun control regulations and firearms mortality rates. However, the link is not as black and white as one might wish – the relationship between firearms regulations and mortality depends on the quality of the law.

The nation's leading public health organization, the Centers for Disease Control and Prevention (CDC), is essentially prevented from analyzing and publishing any epidemiological research that would help us understand what, if any, links there are between gun control and firearms mortality. The Republican dominated congress have done everything they can to prevent the CDC from using any funds to study the issue.

Furthermore, because the CDC cannot (or will not) fund research into gun control, it has lead to a chilling effect on gun control research in academia. According to the Washington Post, "young academics were warned that joining the field was a good way to kill their careers. And the odd gun study that got published went through linguistic gymnastics to hide any connection to firearms."

But maybe because this public health menace can no longer be ignored, a smattering of well done epidemiological research is being published in very high quality medical journals. Let's look at one.

Gun control regulations epidemiology

In March 2016, a group of researchers at Boston University, lead by Dr. Bindu Kalesan, published an article in The Lancet, that examined the relationship between gun-related deaths in the US and three state gun control laws.

The researchers looked at three gun laws (implemented in 25 gun laws in states), along with their effect on firearms mortality:



Firearm identification through ballistic imprinting or microstamping reduced projected mortality risk by 84%;

Ammunition background checks reduced risk by 82%;

And universal background for all gun purchases, including those so-called loophole sales at gun shows and private transactions, reduced risk by 61%.

Furthermore, the researchers stated that implementation of all three of these state-level laws at the Federal level would reduce the national mortality rate from firearms by an estimated 10.1 per 100,000 people (using 2010 statistics) to 0.16 per 100,000. That's a 98% absolute decrease in mortality risk – from a public health perspective, that's like vaccines.

The researchers just didn't pull this data out of the air. They used a cross-sectional study design, which takes observational data from one set period of time, in this case, after implementation of state laws (versus prior to implementation).

Kalesan et al. relied upon a statistical model that determined the independent association of various firearms laws with gun-related homicides, suicides and overall deaths. The researchers also projected the potential reduction of mortality rates if the three most effective firearms laws were enacted at the federal level using state-level data.

And even though the article by Kalesan et al. is the most recent study published in this area, other epidemiological studies have shown similar results. A study by Fleegler et al., published in 2013 in the high impact factor journal, JAMA Internal Medicine, essentially made the same points. The authors concluded that "a higher number of firearm laws in a state are associated with a lower rate of firearm fatalities in the state, overall and for suicides and homicides individually."

One last point. The research from Kalesan et al. wasn't funded by any organization that had a stake in the outcome. In fact, it appears to have been funded by Boston University itself, rather than by any other group.

Remember, these aren't laws that ban weapons. They don't infringe on the mythical Second Amendment rights to own guns. No one is asking for Gestapo agents to march into homes confiscating a hunting rifle (with apologies to Godwin's Law). These are three simple laws that appear to be well-designed to reduce the risk of firearms deaths.

Cherry picking the bad parts

If I were a gun loving right winger, I would find some real and invented issues with the article.

First, the article does state some laws don't work. Of the 25 state-level laws examined, only nine were related to reduced firearms mortality. Nine actually lead to increased mortality risk. And seven showed no observable correlation with increased or reduced risk.

However, the researchers did determine that the three laws mentioned above, firearm identification, background checks for ammunition, and/or universal background checks were statistically linked to lower mortality risk.

To refute the first cherry-pick, it's clear that better gun control regulations actually do have an impact on reducing mortality risk.

Second, the research is a cross-sectional study which ranks below more powerful epidemiological study designs, especially case control or cohort studies. The problem with cross-sectional studies is that they have pretty strong confounding variables (which Kalesan et al. appeared to control), and these studies use data that were gathered for other purposes.

However, this cherry-picked issue can be easily addressed. The study shows some pretty powerful reductions in mortality risk with strong statistical significance. Moreover, there aren't a lot of variables that could impact the data – the question is rather simple, does the risk change at the point the laws change. And the answer isn't a weak yes, it's a fairly robust and powerful yes.

And once again, Kalesan et al. didn't publish this data alone, but in line with other epidemiological studies that support the evidence.

If gun control deniers want to bring equivalent peer-reviewed data, then do so – get it published, and maybe there can be a debate. But as far as I can tell, high quality data that is published in high quality journals that refute the research of Kalesan et al. is lacking.

Summary

According to this new research, laws requiring background checks for both guns and ammunition were the most effective legislative means to lower the risk of firearms mortality. The study clearly shows us the "the protective effect" of state laws that close loopholes in the federal law, which currently only requires criminal background checks only for guns sold through licensed firearm dealers.

Only eight states have universal background checks – California, Colorado, Connecticut, Delaware, New York, Oregon, Rhode Island, Washington. According to this research (which didn't include Washington, since it implemented the law after 2010) , those states generally have lower risks of firearms mortality. The CDC needs to be involved with this research. Remember, if this Congress can block funding for gun research, the next Congress could block the CDC from researching flu vaccines. Or Ebola viruses. Or whatever right wing or left wing crazies want. Despite the lack of involvement of the CDC, we're seeing very powerful epidemiological research, rather than anecdotes, misinformation, and outright lies, that support the facts that even the simplest of gun control regulations can have a profound effect on deaths from guns.

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