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Original article
New Danish standardization of the Child Behaviour Checklist

Jon Henriksen 1, Peter Fraas Nielsen2 & Niels Bilenberg3

1) Department of Oncology, Odense University Hospital
2) Department of Medicine, Svendborg Hospital
3) Child and Adolescent Psychiatric Department, University of Southern Denmark



Introduction: In child mental health services, the Child Behaviour Checklist (CBCL) and related materials are internationally renowned psychometric questionnaires for assessment of children aged 6-16 years. The CBCL consists of three versions for different informants: the CBCL for parents, the Teacher’s Report Form (TRF) and the Youth Self-Report (YSR) for 11-16-year-old children.

Material and methods: The CBCL was standardized in Denmark in 1996, but a need for renewed standardization has emerged because of an update in 2001 and possible cultural changes. We also wanted to increase the response rate and the validity of the national norms.

Results: A total of 949 children from demographically representative schools and their parents were invited to participate. Response rates were high: CBCL 84% (n = 793), TRF 99% (n = 938) and YSR 89% (n = 434). The mean total problem scores, externalizing and internalizing scores, and diagnose-specific sub-scores are presented. Compared with the 1996 standardization, parents rate their children significantly lower in problem score, and the same pattern is found in teachers’ ratings. The young, however, rate themselves higher than previously. Some differences in single-item prevalence have occurred. This may indicate a change in the perception of the problems rather than a shift in psychopathology.

Conclusion: New norm scores and cut-off scores have been generated, and the questionnaires are now available for on-line completion.

Funding: The Danish Mental Health Fund.

Trial registration: not relevant.

In child and adolescent mental health services (CAMHS), the Achenbach System of Empirically Based Assessment (ASEBA) is an internationally renowned set of psychometric questionnaires for assessment of referred patients and for population screening [1-14]. The ASEBA is a screening tool developed to assist the assessment of mental health, and it can be used both by psychiatrists, community-based doctors and psychologists. The forms for school-aged children were introduced in Denmark in 1996 and are currently used in several Danish hospital-based clinics and in a number of child guidance clinics (by educational psychologists).

In this study, the 2001 version of ASEBA for school-aged children (6-16 years) was standardized in a Danish population, thus meeting the need for an update of the former 1996 Danish standardization [2].

ASEBA for school-aged children consists of three questionnaires: The Child Behaviour Checklist for 6-16-year-olds (CBCL) with one of the parents serving as an informant, the Youth Self-Report for 11-16- year-olds (YSR) with the child serving as an informant and the Teacher’s Report Form for 6-16-year-olds (TRF) for collection of teacher information about the indexed child.

The questionnaires are divided into two main sections. The first part taps into the child’s level of social network, school performance and leisure activities. This part is called the "competence section".

The second part consists of 118 problem items. These are statements answered on a Likert scale: zero equals "not true", one equals "partly true or sometimes", two equals "very true or frequently". Summation of all the problem item scores yields a "total problem score". Furthermore, the problem items are divided into two main clusters: "externalizing problems" including conduct, aggressive and antisocial behavioural problems; and "internalizing problems" including withdrawn, depressive, nervous and restrained behavioural problems [1]. Diagnostically meaningful scales, so-called Diagnostic and Statistical Manual of Mental Disorders Version IV (DSM-IV)-oriented scales, have been developed to increase the clinical benefit of the ASEBA material. These scales contain problem items that are frequent among patients with corresponding DSM-IV diagnoses: affective problems, anxiety problems, somatic problems, attention deficit hyperactivity disorder (ADHD) problems, oppositional defiant problems and conduct problems. Nevertheless, the scales are not sufficient as diagnostic tools.

In the present study, the competence scores have not been analyzed as the study focuses only on the problem items.

The total problem score, the internalizing score and the externalizing scores are calculated and compared with those obtained for the 1996 standards [2]. Also included are normative data on the DSM-IV-oriented scales and a list of the most frequent problem items, including comparisons between the recent dataset and the 1996 standards [2].


Normative data were collected in an epidemiological cross-sectional design. Two schools were used as sampling sites. One of the schools was urban (Skt. Hans Skole, Municipality of Odense, 730 pupils) and the other rural (Særslev Skole, Municipality of Nordfyn, 219 pupils); at both schools, parent (household) income was close to the Danish mean [15, 16], and both schools are non-outliers concerning the national Danish grade average [17]. Youths aged 11-16 years filled in the YSR at their school. The CBCL was handed out to all children (aged 6-16 years), who passed them on to their parents. The TRF was typed in by the teachers on a website application. Data from the YSR and CBCL paper forms were keyed into the same database by the study team.

To achieve the highest possible completion rate, gift certificates at a value of 50 DKK for each pupil were handed out to the involved teachers. In appreciation of their valuable efforts, secretaries at the schools were also given a gift. Furthermore, parents who did not return questionnaires were contacted, and the two classes with the highest CBCL answering rate were awarded soft drinks and candy.

Data processing and statistics was done in SPSS for Windows.

Trial registration: not relevant.


A total of 949 children aged 6-16 years (508 boys/441 girls) and their parents were invited to participate. Response rates were high; CBCL 84% (n = 793), TRF 99% (n = 938), YSR 89% (n = 434).

Mean values ± standard deviations (SD) for total problem score, externalizing score and internalizing score are shown and compared with the 1996 normative data [2] below (Table 1).

Comparisons of the mean scores from the 1996 standardization study with the 2010 normative data showed a different pattern, although with the same tendency in gender and age variation for all three questionnaires.

For the CBCL, the 2010 survey produced a significantly lower total problem score for boys aged 6-10 years and a lower externalizing score for both genders and age groups compared with the 1996 data.

For the TRF, we found significant differences between the two surveys as the 2010 survey yielded a lower score on total problem and internalizing behaviour for the age group 6-10 years and in both genders. For the YSR, both genders – in contrast to their parents and teachers – rated themselves higher in the 2010 sample than in the 1996 sample. The following increases in problem score were statistically significant: total problem scores for boys and internalizing score for both genders.

Thus, in the recent dataset, the parent (CBCL) and the teacher (TRF) rating show a decrease in problem load compared with the sample made 14 years earlier, while the youths themselves (as expressed by the YSR) report more problem behaviour now than in 1996.

An overall review shows the same tendency in both surveys: girls score higher on internalizing problems, and boys score higher on externalizing problems. Teachers score boys higher than girls on total problems in both surveys; and in the self-report, girls report more problems themselves than same-aged boys do in both surveys.

The parent-rated (CBCL) DSM-IV-oriented problem scales were analyzed and mean scores, 93rd and 97th percentiles are presented in Table 2.

The most frequently reported single problem items of the CBCL in the two standardization samples were isolated, ranked and compared. The most important differences in ranking within the 14-year time interval are the items concerning "lack of concentration", "use of foul language", "shy" and "headache", which are all ranked as relatively more frequent in the 2010 study sample.

The items concerning "destroying belongings of family members or others" and "self-conscious" are ranked lower in the new study (Table 3).

To evaluate the impact of the lower response rate among parents, we compared the teachers’ ratings of CBCL responders and non-responders (Table 4)


The aim of this study was to standardize the revised ASEBA 2001 forms for school-aged children in a Danish population-based sample.

Several developments since the 1996 standardization have made this new study necessary. Firstly, 14 years have passed since the last normative sample was collected, which means that changes in culture, family structure and trends may be influencing the scoring of children’s problems. Secondly, ASEBA was updated in 2001, and six problem items in the CBCL and YSR, and three TRF items have been exchanged with new and more relevant problem items. Thirdly, the former standardization suffered from a large non-responder group, a problem this survey has avoided by using a different design, i.e. by sampling children from schools instead of via the Danish Civil Registration System.

The 2010 CBCL and TRF mean scores were all lower than those of the 1996 survey. A possible explanation for this may be a change in second-party informants’ perception of problem items. The results in the new study could lend support to a hypothesis often heard that parents and teachers do not know their children/pupils as well as they used to, possibly due to less contact in everyday life. Teachers today have less time per pupil and parents spend less time with their children than before. This is supported by the fact that children score themselves higher at the YSR in the new study sample than in the 1996 sample, which indicates a difference in the perception of problem items rather than a general change in children’s psychopathology.

The 2010 sample shows a relative increase in parents’ report of the item "lack of concentration". This may be a consequence of today’s society having evolved into a multimedia society with an abundance of inputs that can easily distract especially young people: cell phones, computers, television, portable music devices, etc. These "distractors" were also available in 1996, but not to the same extent.

Another problem reported relatively more frequently in the recent sample is "headache". This might indicate a higher level of stress among schoolchildren, but this is speculative.

The item "shy" is ranked higher, and the item "self-conscious" is ranked lower. These differences could be considered to counteract each other, rather than to represent a general tendency.

A new perspective in the use of ASEBA school-age forms is the diagnostic- (DSM-IV-) oriented problem scales. They facilitate a more clinically relevant use of the CBCL, the TRF and the YSR in the primary health sector and in Danish CAMHS. If implemented in general practice, doctors without special expertise in child psychiatry would be able to screen patients for more specific psychopathology before referring them for specialized assessment. This has the potential of saving unnecessary referrals and could be a subject fore further studies.

One of the most important factors when evaluating the quality of the results from this study is to assess the study population’s representativeness. There is a close to equal spread when it comes to gender and age. The sample consists of children from an urban (n = 730) and a rural school (n = 219) on the Danish island of Funen. The population of Funen is very similar to the average Danish population in terms of demographic composition [15]. Compared with the 1996 study in which the sample was a random selection from the Danish Civil Registration System, the sample population of the 2010 survey is not randomly selected and should therefore be considered less representative than the 1996 study population. However, compensating for this, the response rate is considerably higher in the 2010 survey, which diminishes selection bias. As shown in Table 4, the non-responder group scored higher on total problem score, externalizing score and internalizing score than did responders. Non-responding families may be families whose children have a higher problem load. The fact that the non-responding group seems to score differently from the responding group underlines the importance of securing a high participation rate in this type of studies. We have not tried to correct or adjust the CBCL scores based on TRF scores. Instead, we consider normative CBCL scores to be low and recommend that the mean score plus two standard deviations (the 98th percentile) be used instead as the cut-off level for probable cases.


After translation and standardization, the ASEBA materials for school-aged children were introduced in Danish CAMHS about 12 years ago. Now new norm scores have been generated, and the questionnaires are available for on-line completion. The materials, including the school-age forms used in this study, the pre-school forms and subscription to the on-line platform, are distributed from the Research Unit at the Child and Adolescent Psychiatric Department in Odense.

Correspondence: Niels Bilenberg, Børne- og Ungdomspsykiatrisk Afdeling, Psykiatrien i Region Syddanmark, Odense, Universitetsfunktion, Søndre Boulevard 29, 5000 Odense C, Denmark.

Accepted: 26 April 2012

Conflicts of interest: Disclosure forms provided by the authors are available with the full text of this article at

  1. Achenbach TM, Rescorla LA. Manual for the ASEBA School-Age Forms and Profiles. Burlington, Vermont: University of Vermont, Research Center for Children, Youth & Families, 2001.
  2. Bilenberg N. The Child Behaviour Checklist (CBCL) and related material: standardization and validation in Danish population based and clinically based samples. Acta Psych Scan 1999;100:2-52.
  3. Bilenberg N, Petersen DJ, Hørder K et al. The prevalence of child-psychiatric disorder among 8-9-year-old children in Danish mainstream schools. Acta Psych Scand 2005;111:59-67.
  4. Rasmussen NH, Hansen LK, Sahlholdt L. Comorbidity in children with epilepsy I: behaviour problems, ADHD and intelligence. Ugeskr Læger 2007;169:1767-70.
  5. Damsted P, Petersen DJ, Bilenberg N et al. Suicide behaviour in a clinical population of 12- to 17-year-old patients with eating disorders. Ugeskr Læger 2006;168:3797-801.
  6. Bilenberg N, Pedersen D. 3-year follow-up of a child psychiatric cohort Ugeskr Læger 2007;169:1317-21.
  7. Rescorla L, Achenbach TM, Almqvist F et al. Epidemiological comparisons of problems and positive qualities reported by qdolescents in 24 Countries. J Consult Clin Psychol 2007;75:351-8.
  8. Achenbach TM. Integrative guide for the 1991 CBCL/4-18, YSR, and TRF Profiles. Burlington, Vermont: University of Vermont, Department of Psychiatry, 1991:63.
  9. Verhulst FC, Koot HM, Berden GFMG. Four-year follow-up of an epidemiological sample. J Am Acad Child Adolescent Psych 1990;29:440-8.
  10. Hannesdottir H, Einarsdottir S. Icelandic child mental health study: an epidemiological study of Icelandic children 2-18 years of age using the Child Behavior Checklist as a screening Instrument. Eur Child Adolesc 1995;4:237-48.
  11. Roussos A, Karantanos G, Richardson C et al. Achenbach’s Child Behavior Checklist and Teachers’ Report Form in a normative sample of Greek children 6-12 years old. Eur Child Adolesc Psych 1999;8:165-72.
  12. Rudan V, Begovac I, Szirovicva L et al. The Child Behaviour Checklist, Teacher Report Form and Youth Self Report Problem Scales in a Normative sample of Croatian children and adolescents aged 7-18. Collegium Antropologicum 2005:29:17-26.
  13. Rescorla L, Achenbach TM, Ivanova MY et al. Consistency of teacher-reported Problems for students in 21 countries. School Psyc Rev 2007;36:91-110.
  14. Verhulst FC, Achenbach TM, van der Ende J et al. Comparisons of problems reported by youths from seven countries. A J Psych 2003;160:1479-85.
  15. Danmarks Statistik. (1 Jun 2010).
  16. Odense Kommune. (1 Jun 2010).
  17. CEPOS. (1 Jun 2010).

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