Nobody Knows What “Serious Mental Illness” Means

The lack of a single definition of "serious mental illness" negatively affects policy-making, research, and clinical practice.


In an article soon to be published in Psychiatric Services, Lauren Gonzales and her colleagues explore the use of the terms ‚Äúserious mental illness‚ÄĚ and ‚Äúsevere mental illness‚ÄĚ (SMI) in psychiatric research. The authors analyzed 788 articles published between 2015 and 2019 that used a population with SMI. Unfortunately, 85% of the articles did not define SMI. Furthermore, of the articles that did define or attempt to describe SMI, there was substantial variability. The category of SMI, therefore, has no actual agreed-upon definition.

The authors conclude that researchers need to develop more precise and agreed-upon language rather than continue to reference the ill-defined concept of SMI. They write:

‚ÄúReferencing ‚ÄėSMI‚Äô is second nature for many stakeholders. Findings suggest that evidence-based practice and policy efforts should weigh the level of research support, indicating that the construct and the term ‚ÄėSMI‚Äô lacks generalizability. Researchers and stakeholders are encouraged to develop precise and agreed-upon diagnostic language in their efforts to support and advocate for people with mental illnesses.‚ÄĚ

The concept of SMI has been used throughout psychiatry to inform clinical practice and policy. Researchers have taken for granted that SMI is a soundly defined and agreed-upon concept. Researchers have explored the link between diet and SMI, social interventions for SMI, its prevalence and correlates, recovery, etc., without adequately defining this concept.

Many authors have criticized medical and psychiatric research as biased and unreliable. For example, Richard Smith, Editor of BMJ until 2004, was quoted as saying, ‚Äúthe time may have come to a stop assuming that research actually happened and is honestly reported, and assume that the research is fraudulent until there is some evidence to support it having happened and been honestly reported.‚ÄĚ Research has also found extensive undisclosed conflicts of interest in medical research.

‚ÄúData pollution,‚ÄĚ the accidental entry of incorrect data, hinders psychiatric research, as does publication bias. For example, trials with positive results (typically showing that a drug is effective in treating a mental illness) are much more likely to be published, leading to misreporting of results by researchers to make publication more likely.

Bias and deception are common in behavioral research, with researchers consciously and unconsciously manipulating data to produce desired rather than accurate results. In addition, non-financial conflicts of interest, such as allegiances to specific treatments and schools of thought, can bias research.

The pharmaceutical industry commonly sponsors clinical trials of its drugs. This creates misleading results indicating that industry drugs are more effective and safer than they are. Less than half of clinical trials in the EU accurately report results despite legislation requiring that they do. In addition, industry commonly hides studies that do not conform to their desired outcome and underreports the harms caused by their products.

The current work begins by explaining that SMI is given priority in mental health, public policy, and research funding but remains ill-defined across these different domains. The authors also fear that the label SMI can exacerbate the stigma experienced by people already living with other labels such as ‚Äúschizophrenic.‚ÄĚ SMI is not an official diagnostic term for the DSM or ICD, and the APA is variable in its definition. These facts do not make the use of the term any less ubiquitous in the psy-disciplines.

The consequences of SMI having a variable definition are many. The validity and generalizability of research using SMI as a category is damaged. Without a proper definition of SMI, deciding which populations we should direct resources towards becomes less clear. Being given a label of SMI can also hinder individual recovery paths and create increased self-stigma.

To investigate the reliability and validity of the term SMI, the researchers explored 788 papers that utilized the concept of SMI (and other closely related terms such as ‚Äúsevere emotional disturbance‚ÄĚ). 85% of the studies did not define SMI. 26% of the studies provided diagnostic examples of SMI without offering definitions. 37% equated SMI with specific diagnoses, 9% equated SMI with functional impairment, 5% with a duration of the disturbance, and 2% with particular services received. 62% of the studies categorized schizophrenia as SMI, 52% for bipolar, 33% for depression, 14% for mood disorders, anxiety disorders, and personality disorders, and 9% for PTSD.

The definition of SMI changes drastically from study to study, indicating that although the use of this term is widespread, there is no agreed-upon definition. Researchers can’t even agree on what should be observed to determine the presence of SMI. Some point to services received, some to symptoms, others to diagnoses, others to functional impairment, etc. The authors further problematize the term SMI by giving the example of eating disorders. Although eating disorders have the highest mortality rate of any diagnosis, only 1% of the studies examined included eating disorders as SMI.

The authors conclude that researchers need to establish a clear definition of SMI. Without such a definition, the authors suggest it is best to use specific diagnoses, impairment ‚Äúbenchmarks,‚ÄĚ or any other well-defined category to discuss mental disturbances. The authors also recommend that additional research evaluate the use of the term SMI in clinical settings and training programs. They write:

‚ÄúFindings highlight a critical need for establishing clear operational definitions of SMI in the empirical literature. This is a tall order because variations in the definition of SMI are prevalent, with the widespread use of varying definitions.‚ÄĚ



Gonzales, L., Kois, L. E., Chen, C., L√≥pez-Aybar, L., McCullough, B., & McLaughlin, K. J. (2022). Reliability of the Term ‚ÄúSerious Mental Illness‚ÄĚ: A Systematic Review. Psychiatric Services. (Link)


  1. Thank you for this Seriously Needed Investigation of the meaning of Serious Mental Illness. I would like to suggest that one of the overlooked causes of the SMI designation is bad reactions to medications that do not “fit” the patient and in context of possible neglect of medical conditions that impact mental status.

    A young woman was treated with atypical antipsychotic for BiPolar Disorder while her Poly Ovarian Cystic Disorder and inflammation issues were neglected. She suffered terrible akathisia that extended her stay in the acute ward for months; insurance kept paying for it. She was deemed “One of the Unlucky Ones” because even when she was forced to endure maximum titration of antipsychotic, her symptoms were slow to improve. It could be argued that she only improved after enough time elapsed for the lithium* level to become effectual, and that the antipsychotic actually slowed improvement. When she was discharged, on antipsychotic, she still had residual akathisia that produced a personality change to: irritability, restlessness with the need to walk, and quickness to become angry.

    Inflammation issues contributed to future hospital admissions where these scenarios would be repeated and eventually resulted in threat of ECT under the proclamation of “Serious Mental Illness.” A hot debate between advocate and doctor ensued, and at least that time, the advocate was heard, the medication changed, and the patient was able to sleep and resolve her mania.

    The saga continued with much suffering and grief through the years because, I dare say, the term “SMI” is too often used when the allopathic psychiatric protocol is deficiently informed by the medical specialties, resulting in neglect of medical needs that impact mental health while the patient is tormented with the wrong medication.

    Things have gotten better in recent years with signs that the patient’s needs are better understood, finally. The patient’s life could have been so much better if her needs had been acknowledged sooner.

    * Psychiatric literature mentions the anti-inflammatory effect of lithium. I would appreciate if adolescents and young adults could be given opportunity to benefit from natural and less toxic anti-inflammatory treatment while time is taken to identify and treat medical conditions that impact mental health. I believe that a conflict of interest drives a false narrative that First Episode Psychosis should be treated ASAP with toxic and debilitating antipsychotics.

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  2. —-The authors also fear that the label SMI can exacerbate the stigma experienced by people already living with other labels such as ‚Äúschizophrenic.‚ÄĚ

    Exacerbating the negative experiences…please be direct.

    Harold A Maio, retired mental health editor

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        • If I can convince you to call it a “stigma”, whom can I not convince?

          And what do you make of it when someone declines to direct that term? When someone makes the argument, as it was made above, that the reality is prejudice and discrimination. Are they amiss?

          The model I use is WWII Germany: Those millions who agreed “there is a stigma” to specific people, and that much smaller number there who did not.

          Whom would you argue was amiss? Those who conformed or those who did not?

          Harold A Maio

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    • With all due respect Sir,

      “Nobody knows what Serious Mental Illness Means” is an inaccurate title in my opinion because I definitely have a serious mental illness and mine is called schizophrenia. Sadly it is not a label. I cannot snip it off like a designer label. It is in my genes, not my jeans.

      But just because I have a serious mental illness does not mean everyone else has it. Just because I like classical music does not mean anyone else has to.

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  3. I did not mean to infer that there is a “right” medication from among the choices of antipsychotics. Rather, I should have said that a different antipsychotic was more tolerable for her, but still problematic for her in that setting of forced medication. The opportunity to observe the resolution of mania without harmful antipsychotics is usually not allowed, according to my observation. A natural therapy to resolve mania using select amino acids has been reported in the research, but has apparently been neglected in the allopathic setting.

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  4. “severe mental illness” means…

    at best, an object of “cruel compassion” (Szasz). “oh, he’s -schizophrenic- ” or perhaps “too bad; she’s got -severe bipolar- …” on and on. the faux compassion only makes the cruelty worse…colder, more merciless.

    I don’t know the people who work in the psych guilds, but I do think that diagnosis is a political decision is a concept worth revisiting. To say: “this individual is a sick person with “Schizophrenia” and needs treatment…” vs “this pathetic weakling needs to get over it, toughen up…personality disorder if I’ve ever seen it!” and every dsm-label in between speaks volumes to the dynamics of the situation, the people in power and their objectives, and the larger social backdrop. and so…

    I do think some in the psych guilds are well-intentioned or at least…start out that way. I knew one who seemed to be sticking with it just because he had to bring home the bacon, somehow, and…with a family and a graduate degree in psych stuff, what else was he to do? At some point, he came to his senses and realized: the problem wasn’t a couple of bad apples here and there. it was the guild, itself. but…what to -do- about it?

    using stigma, combined with coercion+force+confinement, is a core function of the psych guilds, especially psychiatry. deliberate? Especially with the “experienced professionals,” I’d argue yes. Definitely with those who have a PhD or MD/DO…the higher ups, high priests and priestesses. And…

    I will say that the “real doctors” in the medical establishment now strike me as…generally similar to psychiatrists. For the longest time, I wanted to believe — perhaps I made myself believe? — that “real” doctors were a different breed. I don’t think so, now. Plus, in the US at least, lots and lots of “real doctors” engage in acts of psychiatry on a regular basis. The expert-level witch doctors get called in when it suits the referring physicians’ purposes, in many cases.

    ugh. Back to Szasz…

    Psychiatry is The art of -Lies- . Calling the lowest caste of psychiatrized individuals “severely mentally ill” is a rather clever way of sterilizing and sugar coating “Schizophrenia,” which is psychiatry’s sacred symbol, the ultimate justification for it’s ongoing existence and state-sanctioned powers (again; Szasz). Truth? about that…

    its all lies. why define “severe mental illness” when “Schizophrenia” was and is only vaguely described, and then in ways that magically contracted or expanded, depending on the guild’s aims?

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    • Agree with everything here. A perfect description of the rest of the medical profession. I would have thought that medical doctors would have some pride or sense of honor or respect for science, and not buy into psychiatric quackery, but as you suggested, I guess it serves a purpose for the whole medical profession.

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  5. I do not like the words, “serious”, “severe”, “pervasive” “critical” or “crucial.” Sadly, these words have been abused in relationship to others and me. I was once described as having a “severe and pervasive mental illness.” Other than I am having problems with my spelling, I am fine. I had a “friend” in college who believed her educational pursuits were either “critical” or “crucial” above even our friendship, because, basically, I could not achieve “good enough grades, etc.” by her standards. Later, another friend told me that she was being “abusive” and I should leave the friendship. I, think, about two years later, I dissolved the friendship. And, of course, it leaves the word, “serious.” On my first job out of college, I thought almost everything I did was “serious.” Well, one of my co-workers told me that in a one hundred years, it would not matter. It has been a few decades and I can tell, although, I have an excellent long term memory, I have completely forgotten what was worrying me that I called “serious.” I, think, that might be the problem. We have a tendency to label things, and even people as such. It is not just psychiatry, althought they are obviously big offenders, but all medicine, even education, government, etc. And, then, we so easily forget. And, no, we don’t want to forget and repeat horrific behaviors, etc. but most behaviors, etc. that we label such words are really “trivial” in the scheme of things. I am not human beings are trivial, but, I do think we have a tendency to lack proportion. Each day, we need to look at the sky, a mountain, the stars, the ocean, etc. and then see where we are in all this. We need honest perspective and until we achieve that all will be wanting, especially psychiatry, etc. Thank you.

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  6. I was diagnosed bipolar 1 in 2004/Florida with great, private insurance. Was told ‘it’ was an SMI. Became bankrupt & homeless from side effects.

    Relocated to Arizona (2006] where indifferent family lived. Was reduced to Medicaid/State behavioral health management contractors.

    Drugs were changed 13 times in first 9 months. Landed in ER, admitted to medical floor with bradycardia (heart slowing to fail), doc told my brother (RN) I would not survive. I also had acute akathisia & malnutrition (anorexia).
    When released 10 days later, I expressed outrage to prescribers as I had called to report for help. The guy laughed, said I didn’t say “urgent”.
    A marraige counselor then designated me ‘SMI’, said better quality of care, different clinic.

    Below is ARIZONA’S statutory definition of SMI certification, ostensibly client reviewed every 3 months. BH management gets additional federal revenue for your head count.

    This is not complete…but you’ll get the picture….
    “Inability to live in an independent or family setting without supervision-neglect or disruption of ability to attend to basic needs‚Ķ
    housing, food, and clothing must be provided by others…
    …unable to attend to basic needs of hygiene, grooming, nutrition, medical and dental‚ÄĚ.

    “DTS/DTO, seriously disruptive to community…regularly engages in assaultive behavior…has been arrested, incarcerated, hospitalized…because of dangerous behavior…

    …severe disruption of daily life due to frequent thoughts of death, suicide, or self-harm‚Ķ‚ÄĚ

    ‚ÄúFrequently in trouble at work‚Ķunable to work‚Ķor meet appropriate responsibilities‚ÄĚ.

    “Co-morbidities…like mental retardation, substance dependence…Chronic factors such as social isolation…poverty.

    I was never reviewed in 7 years.
    And here are the FACTS….

    I worked as part of a management team at a large, successful animal rescue…for almost 8 years during this time…running systems, programs, intakes, & donations.
    I PAID OFF my condo & wrote a TOTAL check for a new, modest car.
    I lived alone with a pet, managing my own finances…and everything else.
    No smoking, drinking. Completely med compliant, appointment present.

    SMI, my a**.
    Bottom line, I was a revenue stream and no matter how I behaved and lived…it would never be enough.

    I’m the girl who made them rescind my diagnosis AND @ certification in writing.

    The case workers would have gladly traded for my life…without the drugs, of course.

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    • I was labeled SMI while making a six-figure income, supporting not only myself but my family. Providers are so blinded by bias that they don‚Äôt think to examine patients‚Äô lives at all‚Ķ interviewers choose their questions so they only find what they‚Äôre looking for‚Ķ the SMI designation is as deceptive and harmful as any DSM label, perhaps more so.

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  7. This vague label of SMI is used repeatedly within the psychiatric system to persuade “gate keepers” such as hospital administrators and mental health court judges to allow psychiatrists to do whatever they want to patients, without protection of the patients’ rights by independent review and testimony. Patients are frequently misrepresented to the gatekeepers. The outcome can be disastrous, while their rights are devalued and their exploitation is profitable….(Our daughter was stigmatized with “Serious Mental Illness” (SMI) in the context of professional neglect of her underlying medical issues and forced medication with toxic drugs that do NOT improve the underlying issues….)
    This toxic-drug centered form of psychiatry (allopathic) couldn’t be the economic engine that it is if patients greatly improved. The ubiquitous low-standard of care, where doctors are not held accountable for what they do to patients, makes patients worse. This iatrogenic harm creates new opportunities for exploitation. Patients are used as guinea pigs in drug research funded by Pharma, and in the business of running medical schools. Medical schools need patients on which resident doctors can “cut their teeth” and who can be forced to undergo the lucrative and harmful Electro-Convulsive Treatment, after the toxic drugs have proven to be ineffective and harmful.
    The resultant redistribution of wealth by this ruthless economic engine creates many layers of employment and career advancement in the hospitals and out-patient-“care” systems. When the toxic-drug treatments have ruined the patients’ lives, they are then warehoused by government subsidy, which provides many entry level jobs. The lives of those employed by the psychiatric system become better while existence for too many patients becomes deplorable, yet patient advocates are attacked for protesting the human rights abuse and ruination of their loved ones.
    Doctors who “know the drill” of iatrogenic toxicity and decline, accuse the advocates of fearing that the effect of the drug treatment will be worse than the “SMI”, before the advocates have even learned how quickly devastating the drugs can be. Such a claim is one of the false narratives doctors use to neutralize legal standing and advocacy on behalf of the loved one…You have to see and live this to believe it. It’s monstrous. It happened to us!
    (Our daughter was stigmatized with “Serious Mental Illness” (SMI) in the context of professional neglect of her underlying medical issues and forced medication with toxic drugs that do NOT improve the underlying issues.)

    If anyone reading this with lived experience and knowledge of the psych system as a patient or advocate believes that my claims here are off-base, you are welcome to respond. My conclusions and convictions are based on 16 years of observation and advocacy which has been plenty of time to examine the facts of what happened to us and to “connect the dots” .

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  8. As someone who was misdiagnosed with ‚ÄúSMI,‚ÄĚ I can share what it means: following a 30-minute interview, you‚Äôre placed on a list for the purpose of social control; you‚Äôre unable to access the medical and justice systems without risking your civil and human rights; others are permitted to abuse you and blame you for their own actions, because you will never be believed; and the only path to safety is moving across state lines.

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  9. It’s one of those “you’ll know it when you see it”‘s.

    The problem of language and defining terms enjoys a resurgence every ten years or so and these fundamental questions are being re-asked in all fields of science. Again.

    There are no resolving answers. How can there be?

    Each generation must be reminded of the unknown and humbled.

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