When a person takes his or her own life, stunned survivors often ask, “How could we not have known?” and tell themselves that the fateful act might have been averted if someone had been aware of the victim’s suicidal thinking.

But is there a screening test that could, with some confidence, detect those at risk of committing suicide, and would wide use of it prevent some of the 37,000 suicides that occur annually in the United States? We just don’t know, a federal panel said Monday in a draft report.

The acknowledgment came from the U.S. Preventive Services Task Force after an exhaustive review of existing research. The task force set out to determine whether it would be helpful for primary care physicians to routinely screen all patients for suicide, not just those known to be at high risk—such as those with past suicide attempts, those with depression and other mental illnesses, LGBT youth and those with access to guns.

There’s some reason to think that even with all they have to do during a routine visit, primary care docs might be able to suss out which patients are strongly inclined to harm themselves and direct them to help.

Past studies have shown that 38% of all adults who commit suicide (and 50% to 70% of older adults) have been to see their primary care physicians within a month of taking their lives. Roughly 9 in 10 adolescents who commit suicide had a pediatrician visit in the year leading up to their deaths.

But deciding whether screening would be useful requires that there be mechanisms that can reliably single out the suicidal people from the many troubled or unhappy people who are highly unlikely to harm themselves.

In drafting its preliminary findings, the Preventive Services Task Force found that existing screening questionnaires vary widely. There were tests capable of identifying those who would commit suicide 100% of the time, but somewhere between 60% and 80% of those identified as suicidal would not, in fact, go on to commit suicide.

Then there’s the question of whether the deployment of a perfect screening mechanism would get those identified by it the help they need. On that front, the draft report says, there is little consensus.

Among adolescents identified as being at high risk for suicide, receiving psychotherapy did not appear to reduce the likelihood of suicide, and in some studies it was linked to a higher risk of suicide. Among adults, the pooled results of 11 studies showed that receiving psychotherapy drove the suicide rate down by 32%.

Under the Affordable Care Act, the findings of the U.S. Preventive Services Task Force can be a powerful prod to changes in policy. Had the panel determined with confidence that screening for suicide saves lives, most insurers would be required to cover the screening and the consequent referrals—in this case, most likely for psychotherapy—without requiring a co-payment on the part of the patients. And school-based suicide screening programs such as the now-defunct Teen Screen would potentially flourish.

But, as was the case in 2004, the panel has tentatively decided there is insufficient evidence to make that determination.

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Los Angeles Times