Psychiatrist Robert L. Spitzer. (Courtesy of the Spitzer family)

In the tumult of the 1960s, psychiatry found itself under siege. Critics said the field lacked scientific standards — failing to help many truly troubled people while medicating or institutionalizing others who suffered from nothing more serious than nonconformity.

As he sat listening to his patients talk through their problems, a fledgling Columbia University psychiatrist named Robert L. Spitzer was nagged by doubts, too. “I was always unsure that I was being helpful,” he told the New Yorker years later, “and I was uncomfortable with not knowing what to do with their messiness.”

He struggled to find a place in his profession. He ended up transforming it.

Dr. Spitzer died Dec. 25 at 83 in Seattle of complications from heart disease, said his wife, Janet Williams. He also had Parkinson’s disease.

In his prime, he dove headfirst into one of the era’s most heated debates. He brokered the American Psychiatric Association’s landmark 1973 vote to stop treating homosexuality as an illness. Then, taking the helm at the APA’s Diagnostic and Statistical Manual of Mental Disorders (DSM) — regarded as the profession’s bible — he led an unprecedented push for uniform standards in an often ambiguous discipline.

He added dozens of mental disorders to the psychiatric lexicon: anorexia, bipolar disorder, panic disorder, PTSD and many other now-familiar maladies. It’s not that these ailments didn’t exist before the 1970s — but they had no agreed-upon names or definitions until Dr. Spitzer branded them in two new editions of the DSM. The book tripled in size (from a 134-page paperback to a 567-page doorstop) and at least as much in influence under his leadership.

Dr. Spitzer’s work changed the treatment of many mental illnesses, as well as the way insurance companies paid doctors for that treatment. It opened the door to new epidemiological research: Once doctors had a common understanding of which symptoms defined which illnesses, they could deploy assistants with simple checklists to track the prevalence of those conditions across large populations.

And the cumulative effect of his work raised public awareness, as newly christened disorders were showcased on the cover of Time or hashed out on “Oprah.”

Dr. Spitzer liked to provoke, and that may have shortened his reign at the top of his field. He sparred with old-line Freudians when he banned their cherished word “neurosis” — Dr. Spitzer, fixated on tangible symptoms, had no patience for the mysteries of unconscious conflict. He enraged feminists when he tried to classify PMS as a mental illness.

And he nearly undermined his social-justice legacy when, late in his career, he championed therapies to “cure” homosexuals. His 2001 study on the topic was pilloried by colleagues and gay rights activists alike for shoddy methodology, and in 2012, he retracted it.

“I don’t know that I’ve ever seen a scientist write a letter saying that the data were all there but were totally misinterpreted,” he told the New York Times that year. “Who admitted that and who apologized to his readers.”

A curious rebel

The traits that made Dr. Spitzer a magnet for controversy were the same that fueled his psychiatric revolution: a desire to challenge the establishment, a mania for data and order, and a perpetually curious mind.

As a medical student at New York University, he published a paper challenging a major study by a prominent faculty member. During his residency at Columbia, he took computer classes on the side. He would go on to co-develop software to help doctors make psychiatric diagnoses.

His career was somewhat aimless, though, until a chance encounter in the Columbia faculty dining room in 1966. A colleague mentioned that he was serving on a committee for the DSM-II — the first major revision of the APA’s 1952 directory of disorders — and asked if Dr. Spitzer would help.

Initially, his role was modest. But it gave him a front-row seat to the debates roiling his profession. After the 1969 Stonewall riots in New York’s Greenwich Village, gay activists were energized to agitate for more rights, and in the early 1970s, they noisily invaded APA conferences to protest homosexuality’s classification as a mental illness.

It wasn’t just a stigma on paper: Some gay men and lesbians couldn’t get treated for depression or anxiety because doctors focused solely on their orientation; others were pressured into therapies involving hormones or electric shocks.

After a clash at a 1972 meeting of behavioral therapists in New York, Dr. Spitzer decided to hear the protesters out. Personally, he believed then that homosexuality was an illness, he later told public radio’s “This American Life.” But forever the devil’s advocate, he organized a panel for both sides to air their arguments at the 1973 APA conference in Honolulu.

There, an activist brought Dr. Spitzer to a secret tiki-bar gathering of closeted gay psychiatrists. Many had prestigious credentials, which convinced Dr. Spitzer that homosexuality was not some crippling condition.

Ultimately, Dr. Spitzer’s was the loudest voice arguing to drop homosexuality from the DSM. When old-guard psychiatrists pushed back, Dr. Spitzer appealed with logic.

“A medical disorder,” he explained to The Washington Post at the time, “either had to be associated with subjective distress — pain — or general impairment in social function.” If gays were happy being gay, then where was the disorder? But he offered a deft compromise: In subsequent printings of the DSM-II, homosexuality was replaced with “ego-dystonic homosexuality,” the condition of gays or lesbians unhappy with their orientation.

His success in handling the gay rights uproar paved the way for Dr. Spitzer to chair the task force for the next edition of the DSM — though, as Hannah Decker wrote in her 2013 history “The Making of DSM-III,” he faced no competition “because no one paid much attention to the DSM” at the time.

He had his work cut out for him. The medical establishment was realizing that it had little grasp on how many people had mental illnesses or what kind. One study found that New York had much higher rates of schizophrenia than London, which saw many more patients with manic depression. Something in the water? No — it was just that doctors in the two cities defined those illnesses differently. Other studies found that multiple psychiatrists, assessing the same patient, rarely came up with the same diagnosis.

What psychiatry needed, Dr. Spitzer believed, was a common language to describe mental illnesses.

He filled the DSM-III committees with psychiatrists who shared his fervor for data and description. In somewhat chaotic meetings, they would shout suggestions for new disorders, which often went straight into Dr. Spitzer’s typewriter for publication.

Old, broadly defined conditions were broken into more specific ones. “Anxiety neurosis” was replaced by panic disorder, social phobia and generalized anxiety disorder. Judgmental terms such as “frigidity” were swapped out for clinical ones such as “inhibited sexual desire.”

The number of entries grew, and so did the size of each entry: Dr. Spitzer’s team delineated each disorder with a detailed checklist of symptoms necessary to reach that diagnosis.

Dr. Spitzer gladly waded into the fights that erupted over his new classifications. Darrel A. Regier, who worked on the DSM-III task force, accompanied Dr. Spitzer to the APA assembly to defend one proposed disorder in dispute: tobacco dependence.

At the time, nearly 40 percent of adults smoked. Many doctors were wary of linking a common bad habit to mental illness, and the tobacco industry was flaring. But Dr. Spitzer unveiled a shocking photo — a throat cancer victim smoking a cigarette through his tracheotomy hole.

It was a vivid way to underline the power of addiction, said Regier, a former director of research for the APA. “Bob said, ‘Look, maybe everybody isn’t at the stage of this guy, but this can be a serious addictive disorder,’ ” Regier recalled. Tobacco dependence made the cut.

The DSM-III was a sensation upon its 1980 release; along with a 1987 revision that Dr. Spitzer also oversaw, it sold 1 million copies. But as the APA geared up for the manual’s fourth edition, the leadership replaced Dr. Spitzer, regarded by some as too dominant and heavy-handed.

He remained with the DSM as a senior adviser — but also, occasionally, a critic. In 2012, he publicly fretted that the hyper-detailed system he had birthed was becoming too vast and ran the risk of pathologizing utterly normal behavior.

In 1999, he had another pivotal encounter with protesters at a conference: “ex-gay” activists, demanding attention for therapy they claimed had reversed their orientation. Dr. Spitzer agreed to study it.

He interviewed 200 men and women who had been through what was known as sexual reorientation or reparative therapy — and concluded in a 2001 paper that most experienced a significant change in their patterns of sexual attraction.

Critics blasted his study for relying on the distant memories of his subjects, many of whom were agenda-driven activists who had undergone a hodgepodge of impossible-to-compare therapies, from psychiatric counseling to Bible study.

Dr. Spitzer argued that he was merely trying to promote discussion. But the criticism wounded him: He had always prided himself as a stickler for standards. And he was horrified to see his work touted by anti-gay social conservatives. “On every social issue,” he told The Post in 2005, “I totally disagree with the Christian right.”

In 2012, after meeting a gay journalist who described the painful debacle of his own attempt at reparative counseling, Dr. Spitzer retracted his study.

Sneaking out for therapy

Robert Leopold Spitzer was born on May 22, 1932, in White Plains, N.Y., to the children of Eastern European immigrants. He recalled his relationship with both parents as difficult — his engineer father was cold and distant, his mother in chronic grief over his older sister’s death from meningitis.

But he took a briskly rational approach to grappling with his complicated childhood, as well as the upheavals of adolescence. As a pre-teen, he drew graphs to chart his fluctuating feelings about the girls in his life. And during high school, he sneaked out for $5 weekly analysis sessions.

He enjoyed the talking part but grew skeptical about the “orgone accumulator” his therapist had him sit in — an iron box, devised by psychoanalyst Wilhelm Reich, that could supposedly cure various mental woes.

As a Cornell undergraduate, Dr. Spitzer wrote a paper debunking “orgone energy” theory. It was turned down for publication, but the FDA asked the young man to serve as an expert witness in a federal fraud case against Reich. He graduated from Cornell in 1953 and from New York University medical school in 1957.

A self-described workaholic, Dr. Spitzer had an early marriage in college that ended in divorce. A second marriage, to a fellow doctor, Judith Berg, produced two children but crumbled after nearly 20 years as he threw himself into the DSM-III.

He met his third wife — Janet Williams, a social worker who eventually became a Columbia professor — when he hired her to work on that project. They had three children. Besides his wife, survivors include his children and four grandchildren. Dr. Spitzer moved to Seattle from Princeton, N.J., in August.

CORRECTION: An earlier version of this obituary incorrectly noted the results of a groundbreaking study that influenced Dr. Spitzer’s work. The research found that London hospitals were much more likely to diagnose patients with depression, while New York hospitals reported much higher rates of schizophrenia, not the other way around. The obituary has been revised.