At least three medical associations are offering condolences to the victims of the mass shootings in Texas and Ohio while urging lawmakers to take measures to curb the likelihood of similar attacks in the future.

Nearly 30 people were killed in the two shootings, which happened less than 24 hours apart. In prepared remarks on Monday, President Donald Trump linked mass shootings to violent video games and mental health, but experts point out that neither has been proven to motivate most shooters.

The American Psychological Association in particular has pushed back at suggestions that mental health is to blame for most mass shootings. Rosie Phillips Davis, elected president of APA, said in a statement that linking mental health to mass shootings "is unfounded and stigmatizing."

"Research has shown that only a very small percentage of violent acts are committed by people who are diagnosed with, or in treatment for, mental illness," she said. "The rates of mental illness are roughly the same around the world, yet other countries are not experiencing these traumatic events as often as we face them. One critical factor is access to, and the lethality of, the weapons that are being used in these crimes. Adding racism, intolerance and bigotry to the mix is a recipe for disaster."

The Texas shooter was reportedly motivated by hatred for immigrants. In a statement, Patrice Harris, elected president of the American Medical Association, said "everyone in America, including immigrants, aspire to the ideals of life, liberty and the pursuit of happiness."

"Common-sense steps, broadly supported by the American public, must be advanced by policymakers to prevent avoidable deaths and injuries caused by gun violence," Harris said. "We must also address the pathology of hatred that has too often fueled these mass murders and casualties."

The American Public Health Association went even further in its call for action, urging the U.S. Senate to pass House legislation expanding the use of background checks for gun purchases and freeing up federal funds for research into gun violence.

"This senseless loss of life is all too common in the United States," APHA Executive Director Georges Benjamin said in a statement. "For the families, friends and communities of these victims, this pain will never pass, just as it will not pass for the loved ones of the thousands of other people who have died from gun violence in the U.S. in recent months. Even one mass shooting is too many, and we have seen more than 250 of them this year. The time for this to end is now."

As of Monday morning, the Entertainment Software Association, which represents video game developers, had not responded to allegations that video games share blame for mass shootings. The National Shooting Sports Foundation, which represents gun manufacturers, also had not issued any statements.