The 9-question survey many doctors use to diagnose depression was actually created by an antidepressant manufacturer

• Primary care doctors routinely use a 9-question survey to screen for depression.
• It was designed by a Zoloft marketing guy who worked for Pfizer in the 90s.

If your doctor suspects you might have depression, there's a go-to questionnaire they might pull out with nine questions to answer about how you've been feeling over the past two weeks.

The questions touch on a range of potential issues, from sleep disturbances, to appetite changes, concentration issues, and your general enjoyment of life.

Many experts say this tool, called the PHQ-9, was never meant to be a definitive diagnostic test aimed at diagnosing mental health issues. It was designed as a first-ditch screening tool; a conversation starter between doctor and patient.

But for primary care physicians strapped for time in the exam room, it is often used as a stand-in for a more in-depth clinical evaluation — a go-to prescribing tool for antidepressants.

Critics say the issue is that it this tool was developed by Pfizer, shortly after Zoloft came on the market.

"These forms have a very low criteria for anxiety and depression," UK-based psychotherapist James Davies, co-founder of the Council for Evidence-based Psychiatry, told the Telegraph in 2017. "It's about getting people in and out of the door in 10 minutes," often, with a prescription in hand.

As reporter Olivia Goldhill details in a wide-ranging Stat report out this week, the marketer who first dreamed up the idea for what later became the PHQ-9 — the quick tool that ultimately made many primary care doctors more comfortable prescribing antidepressants from exam rooms worldwide — was a "marketing man" working for Pfizer. Howard Kroplick convinced the company to invest in the pricey research required to develop the now-ubiquitous questionnaire.

"It wouldn't have happened if it wasn't for me," a now-retired Kroplick told Stat, in his first public conversation about how the tool he lobbied for was originally designed and conceived.

The PHQ-9 had to fit neatly into the confines of a 15-minute doctor's visit

Studies suggest the PHQ-9 vastly over-counts who's depressed.

The tool wasn't poorly designed: the licensed professionals hired by Pfizer to build this test say it was never meant to diagnose depression in a vacuum.

Pfizer isn't the only drug-maker that developed such quick-draw screening tools in conjunction with researchers and clinicians, either. Eli Lily, the first company to get an SSRI on the market in the US, worked with researchers who made similar tools.

The goal of all these prompts wasn't inherently malicious. Physicians and psychiatrists who developed them say they truly hoped these questions might help solve a real problem — providing an unmet need for more mental health treatment to patients via routine doctor's visits.

But this kind of screening, in order to be done thoughtfully, doesn't realistically fit into the timeframe of a typical doctor's visit. It must be followed up with a more robust clinical evaluation than a 15-minute exam can offer, and a differential diagnosis that excludes other similar and often intertwined conditions, like anxiety, alcoholism, eating disorders, ADHD, and trauma.

"Their marketing strategy, which worked brilliantly, they wanted to move prescriptions out of psychiatry, which is a small specialty, and into primary care," psychologist Jonathan Shedler, who consulted for Eli Lilly in the 1990s, told Stat. "No one had incentive to say it looks like depression, but it's a symptom of trauma or depression secondary to substance abuse."

The rise of questionnaires like PHQ-9 has led to more antidepressant prescriptions, for better and for worse

Study after study shows it's impossible to simplify depression into a simple one-page questionnaire. Recent research suggests depressed men often don't even register on such screenings, because their depression manifests more like anger than sadness or withdrawal. And the mental health of teenagers, especially teen girls, has been in a freefall for the past decade, even though antidepressants are more prescribed than ever, in both teens and adults.

While antidepressants work well for some people some of the time, taken in isolation, they're not great for most patients. Drugs can work to ease depression symptoms, but so can other interventions, like psychotherapy, physical exercise, or mindfulness.

Irving Kirsch, a psychologist and lecturer at Harvard who's studied antidepressants for decades, said that often "when you go to your doctor, the first thing they suggest is an antidepressant."

In part, the issue comes down to access, simplicity, and the cost of different treatment options. Generic antidepressant pills are generally much easier, faster, and cheaper to dispense than things like therapy, or even group meditation.

"I tend to think about depression as often being a normal reaction to a bad state of affairs," Kirsch previously told Insider. "That doesn't mean it's not serious. It's very serious! A normal reaction to falling off a high ladder is to break your bones. But the cause is something that doesn't indicate there's something that was wrong with you."