The next DSM will name biology it cannot yet measure

The load-bearing move here is definitional. A biological factor, in the committee's usage, is a mechanism that may be involved in how a disease develops but has not yet become something a lab can quantify, and it may be physiological, genetic or biochemical ^[8]. A biomarker is a characteristic you can measure, by blood test or imaging, and use to track a biological process or a response to treatment ^[9]. Diabetes has hemoglobin A1C; oncology has the scan that sizes a tumor ^[10]. Psychiatry has certain proteins used to diagnose Alzheimer's disease, and nothing else that qualifies ^[1].

So the arithmetic of the new material is one condition with a measurement and every other condition described in terms of factors ^[15]. That is not a quibble about phrasing. Clinicians diagnose from this book and scientists use it to guide research ^[2], so the wording of a factor becomes the wording of grant applications and chart notes long before any assay exists to settle what it means.

The subcommittee is also arguing with its own unit of analysis. Researchers treat psychiatric conditions as behavioral syndromes whose signs overlap, and patients routinely meet criteria for anxiety and mood disorders at the same time, as they do for schizophrenia and bipolar disorder with psychosis ^[12]. Listing those as discrete conditions is called an oversimplification, because they cluster through shared genetic and environmental factors, and depression and schizophrenia probably contain subgroups that resemble each other while developing through different pathways, which is why one biomarker per label is unrealistic ^[13]. The manual is organized by the labels its biology subcommittee says do not carve cleanly.

There is a precedent for that awkwardness, and the account offers it: tuberculosis, cancer and diabetes were recognized as clusters of signs and symptoms before anyone could pinpoint the mechanisms, and psychiatry sits before that turn rather than after it ^[14]. The difficulty is that the DSM-5, out since 2013, was already criticized for lacking objective biological measures in a way that critics said risks medicalizing human suffering and weakening the validity of diagnoses ^[4]. Naming mechanisms nobody can measure does not answer that objection. It restates it with biological vocabulary. And the separation is genuinely hard: family history and trauma are primary risk factors, and the biological changes are subtle enough that current technology cannot easily capture them ^[11].

What the account does not supply is a date. The American Psychiatric Association has said only that the next edition comes in the coming years ^[5]. The disclosure comes from a former committee member writing in The Conversation, whose term ran 27 months, from May 2024 to August 2026 ^[6][16].