Childhood psychopathology can be really bad for your health.

It is not often that one is asked to provide a commentary on an article that one expects to become a cornerstone of justifications for new psychiatric research (and especially longitudinal and developmental research), but that is what ‘‘Childhood Problem Behaviors and Death by Midlife: The British National Child Development Study’’ is. It is also scary to claim that this is the first study of its kind (there is always the fear that someone better read will point out that X showed something similar in the 1920s), but I believe it is. This admirably concise presentation from the 1958 British birth cohort indicates that children rated by their teachers as being in the highest scoring quartile on a more than 40-yearold questionnaire about emotional and behavioral problems had about double the mortality by age 46 years of children scoring in the lowest quartile. Of course, mortality by age 46 years was low overall (approximately 1.5% in the lowest male and female quartiles and approximately 3% in the highest quartiles), but in epidemiological terms, that is a huge effect, affecting a large number of people. If this disparity were to continue throughout life, it would amount to an unprecedented number of life-years lost to an easily measured childhood risk factor affecting so large a proportion of the population. The article also reports that ‘‘externalizing’’ problems had a greater effect on death rates than ‘‘internalizing’’ problems and that the ‘‘internalizing’’ effect was largely explained statistically by familial factors and ‘‘externalizing’’ problems. The problem is that the seemingly familiar terms externalizing and internalizing, as used here, do not mean what they usually mean. As described in the Measures section of the article, the 146 items of the Bristol Social Adjustment Guide measured 10 ‘‘syndromes’’ that were clustered into two overarching dimensions called overreaction and underreaction. Presumably, because this more than 40-year-old conceptualization has been entirely superseded, the authors simply renamed the syndromes ‘‘externalizing’’ and ‘‘internalizing.’’ However, the overreaction (‘‘externalizing’’) dimension included ‘‘anxiety about acceptance by children’’ and ‘‘anxiety about acceptance by adults,’’ although these items clearly belong under the internalizing umbrella as it is currently understood. Similarly, ‘‘writing off adult values’’ is now seen as part of the externalizing spectrum, but because it was part of the conceptualization of ‘‘underreaction,’’ it is placed in the ‘‘internalizing’’ scale. One further overreaction syndrome (‘‘inconsequential behavior’’) has no obvious parallel in the modern assessment of internalizing or externalizing disorders, but here it counts toward ‘‘externalizing.’’ The key point is that both the ‘‘externalizing’’ and ‘‘internalizing’’ scales here are mixtures of what we would now regard as internalizing and externalizing symptoms. So we cannot conclude that behavioral problems had greater direct impact on mortality than did emotional problems. However, this question could have been addressed had the syndromes been grouped in a manner more in keeping with current definitions of internalizing and externalizing problems. Perhaps the original syndrome level scores were not recorded, or are no longer available, but if they are, then I would be interested to know what effects rescoring along the lines I have suggested would have. In discussing their results, the authors briefly consider two potential mechanisms by which these effects on mortality might have arisenVsusceptibility to risky and self-harmful behavior (which they suggest might be principally responsible for their findings) and low socioeconomic achievement. Because no data on the actual causes of death were available (perhaps in future research, the authors could access such information from the death certificates flagged in the National Health Service Central), it is perhaps understandable that they decided not to present a detailed discussion of this issue. However, I think it is helpful to consider a rather broader and more differentiated set of possible mechanisms. In this regard, I find it useful to consider six groupings of explanations that Accepted September 15, 2008. Dr. Angold is with the Department of Psychiatry and Behavioral Sciences, Duke University Medical Center. Correspondence to Adrian Angold, M.R.C.Psych., Box 3454 DUMC, Durham, NC 27710; e-mail: [email protected] 0890-8567/09/4801-0003 2008 by the American Academy of Child and Adolescent Psychiatry. DOI: 10.1097/CHI.0b013e3181908c49 E D I T O R I A L