“Diagnosing Babies? Diagnosing Disorders in Babies?” Some thoughts on the ZERO TO THREE TASK FORCE response

Recently I conducted a diagnostic session with a 25-month-old boy and both his parents. The parents were very fond of their boy, who was their first child, but they were also convinced that he was severely disturbed. They regarded him as extremely overactive and impulsive, told me that soon after birth he would hold his head high in order to anxiously observe his environment, always appearing very tense. I knew that there had been many problems during the first years, starting with a delivery which the mother had experienced as traumatic, a long period of postnatal depression, feeding problems, etc. The mother had subjectively experienced her boy as aggressive and hostile, and herself as insufficient. The father somehow agreed to her way of looking at things. During the session the boy was constantly moving around, exploring, somehow shy towards me, but nevertheless approaching me because he wanted to have the pen in my breast pocket. When I said “no” but gave him some colored paper instead, he was satisfied for a while but then started to beg for my pen again. From time to time he went to both parents, sat on their lap for a few seconds, but then separated and continued to move around. He knew and expressed some words, especially “no”, when his parents limited dangerous activities.

During the session I thought about my short paper in Perspectives and the thoughtful response that we received from the Zero to Three Task Force (ZTTTF). Should I make a clear statement that the boy has a diagnosable disorder, and if yes, what could be the right diagnosis? Was the level of observable activity and impulsivity beyond “developmentally and culturally expected norms”? There was clear impairment, at least in the parent-child relationship; the parents suffered, and this also caused suffering in the boy. I felt insecure and thought of attending one of the next available Zero to Five training courses. If I assumed that the observed behavior was within the norms, then it could be a relational disorder, because the problematic behavior might only occur in the relationship with the parents. But the boy’s behavior towards his parents did not seem to be abnormal. It was abnormal in the minds of the parents: there seemed to be a disorder in their “enfant dans la tête” (Soulé, 1982). What counts? The clinical observation and the norms of the clinician, or the internal reality and norms of the parents? What I saw supported my agreement with the concluding statement of ZTTTF that we have to acknowledge that young children (and their parents) “suffer distress and functional impairment as well as jeopardized development stemming from different types of psychopathology.” The diagnostic process with young children is so challenging because the interpersonal and intrapsychic aspects are inextricably linked to each other in the early years.

Continuity vs. discontinuity of symptoms and disorders?

But there are also risks. What does the communication of a diagnosis mean for the course of further development? From preschool age on there seems to be some continuity for example of hyperactivity symptoms into adolescence, but in general the level of symptoms decreases over time (Lahey et al., 2016). Meeting the criteria of an early diagnosis predicts functional impairment over time fairly well, but is much less reliable in predicting the stability of a specific disorder (Biederman, Mick, & Faraone, 2000). On the other hand, we should not forget that establishing a diagnosis is also a way of intervention, maybe not always to the better. For example, telling parents that their toddler’s problems seem to be best characterized as specific disorder might enhance their understanding of their child’s behavior on the one hand, but can also lead them to a parental attitude to protect him/her from age-adequate developmental challenges and to developmental restraints on the other.

Categorical vs./and dimensional?

Without doubt I support the ZTTTF notion that developmentally sensitive diagnoses describe patterns of symptoms and impairment and not children’s traits. My research group is currently conducting a longitudinal study on internalizing symptoms and anxiety/depression disorders from preschool to late school age. We use both categorical and dimensional approaches to describe early internalizing problems. My impression is that the longitudinal description of symptom trajectories is better suited to describing the developmental dynamics of psychopathology than the early application of diagnostic categories. I agree that the decision to recommend therapeutic intervention or not is also a categorical decision. But this decision might be better served by assessing risk profiles (Bufferd et al., 2014) such as temperamental characteristics, parental psychopathology and/or early life stress than by applying early diagnostic categories. We should treat infants and their parents when they show high-risk profiles even if the symptoms do not meet diagnostic criteria. Studies on the course and taxonomy of psychopathology have shown that higher-order dimensions like externalizing/internalizing or even general psychopathology factors show more continuity then more singular criteria of categorical diagnostic categories (Forbes, Tackett, Markon, & Krueger, 2016; Kotov et al., 2017).

Comorbidity or heterogeneous symptom clusters?

I fully agree that we would treat a young child who exhibits anxiety and overactivity differently from a child with activity problems alone. Nevertheless – as (Goldberg, 2015) rightly argues – the notion of co-morbidity is misleading. “The term ‘co-morbidity’ was introduced in medicine to denote those cases in which a ‘distinct additional clinical entity’ occurred during the clinical course of a patient having a particular illness. Thus, while a person with both schizophrenia and peptic ulceration might reasonably be said to have two co-morbid disorders, a person with major depression and an anxiety disorder cannot––the illnesses are not really distinct. The illusion of the DSM-5 approach to common mental disorders can really only be sustained by drawing borders where none exist” (p. 2). I would hypothesize that this is even more so in early childhood. In the case of the young child with anxiety and overactivity symptoms, a clinical appraisal of whether the child expresses his/her anxiety through motoric activity might be more helpful for setting up psychotherapeutic strategies then a concept of the child having two co-morbid disorders, each of which needs a different approach.

Extending the concept of ADHD to early childhood?

Just as I agree with the ZTTTF that we must overcome our own uneasiness about clearly and concretely talking about young children’s difficulties and disorders, I am still very skeptical with respect to extending the concept of ADHD to early childhood. Recently I asked a 6-year-old in our child psychiatry unit why his parents had brought him to the hospital, and he responded: “I was brought here because I am ADHD!” This shows how essential it is that we should diagnose disorders and not children, and I am very grateful to the ZTTTF for emphasizing this clearly in its statement. Nevertheless, a diagnosis, and especially an early one, can have a tremendous impact on the child’s self-concept, and the parental concept of their child as well. In fact, there are data which show that high levels of motor activity, impulsiveness, and especially inattention can predict more severe problems in later life, but hyperactivity symptoms usually decline as the child grows older and the predictions are less syndrome specific and more valid with respect to global functioning and developmental impairment (Biederman et al., 2000). Excessive motor activities can be seen as first precursors of ADHD and are observed by parents as early as their child’s toddlerhood, but they are barely distinguishable from highly variable normative behavior during the first years of life. I appreciate the clarification from the ZTTTF that their members advocate for non-pharmacologic treatments, but I still remain hesitant because experience shows that when a disorder concept is broadened to include new age groups, the next step of introducing the pharmacological treatment is usually not far away. We have seen this trend in the USA, where the extensive increase of bipolar disorder diagnoses during childhood led to a tremendous use of drug treatment for children, a tendency that was not seen in Europe or other continents. I thank ZTTTF for reminding us that the first use of benzedrine, a drug containing amphetamine, in children initially led to positive effects: Hyperactivity decreased and concentration increased. But Bradley(1937) already warned: “Any indiscriminate use of benzedrine to produce symptomatic relief might well mask reactions of etiological significance which should in every case receive adequate attention.” (Bradley, 1937). Amphetamine was soon bought on the black market because it mobilized power and enhanced self-confidence. Methylphenidate was first synthesized by Leandro Panizzon in 1944 for the Swiss company Ciba. In a self-trial, his wife took the substance and responded enthusiastically because her abilities to play tennis improved dramatically. Panizzon named the drug “Ritalin” because of his successful wife’s name Rita. It was brought to the market in 1954 and blazed a trail of success that is still ongoing after more than 60 years.

Although I have expressed some concerns, I want to thank the members of the Zero To Three Diagnostic Classification Task Force for the enormous work they have done in assembling all the clinical experience and scientific knowledge to create this new version of the classification system. I also thank them for being open and flexible enough to deal with the critical discussion that I know is conducted in the international infant mental health field. There are arguments for and against, coming from different clinical concepts, scientific approaches, and cultural backgrounds. Listening carefully to what clinicians and scientists from diverse cultural and professional backgrounds have to say and dealing with their concerns in an open, respectful discussion is essential and will move our field forward.


Biederman, J., Mick, E., & Faraone, S. V. (2000). Age-Dependent Decline of Symptoms of Attention Deficit Hyperactivity Disorder: Impact of Remission Definition and Symptom Type. American journal of psychiatry, 157(5), 816–818.

Bradley, C. (1937), The behavior of children receiving benzedrine. The American journal of psychiatry, 94 (3), 577–588.

Bufferd, S. J., Dougherty, L. R., Olino, T. M., Dyson, M. W., Laptook, R. S., Carlson, G. A., & Klein, D. N. (2014). Predictors of the onset of depression in young children: a multi-method, multi-informant longitudinal study from ages 3 to 6. Journal of child psychology and psychiatry, and allied disciplines, 55(11), 1279–1287.

Forbes, M. K., Tackett, J. L., Markon, K. E., & Krueger, R. F. (2016). Beyond comorbidity: Toward a dimensional and hierarchical approach to understanding psychopathology across the life span. Development and psychopathology, 28(4), 971–986.

Goldberg, D. (2015). Psychopathology and classification in psychiatry. Social psychiatry and psychiatric epidemiology, 50(1), 1–5.

Kotov, R., Krueger, R. F., Watson, D., Achenbach, T. M., Althoff, R. R., Bagby, R. M., . . . Zimmerman, M. (2017). The Hierarchical Taxonomy of Psychopathology (HiTOP): A dimensional alternative to traditional nosologies. Journal of abnormal psychology, 126(4), 454–477.

Lahey, B. B., Lee, S. S., Sibley, M. H., Applegate, B., Molina, Brooke S G, & Pelham, W. E. (2016). Predictors of adolescent outcomes among 4-6-year-old children with attention-deficit/hyperactivity disorder. Journal of abnormal psychology, 125(2), 168–181.

Soulé, M. (1982). L’enfant dans la tête – l’enfant imaginaire. In T. Brazelton (Ed.), La dynamique du nourrisson (pp. 135–175). Paris: Les Éditions ESF.


Kai von Klitzing, M.D.
President of WAIMH