The study was conducted in November/December 2010 in Liaoning Province, northeastern China. The province of Liaoning has a population of 48 million and includes three major cities of 1,000,000 ≥ each; seven average cities of 500,000 to 1,000,000 inhabitants each; and four small towns with 200,000 to 500,000 inhabitants each. Three of the 14 cities (one metropolitan city, one medium-sized city and one small) were chosen at random. Of these, three urban areas in each city and two municipalities in large and medium-sized cities were chosen at random. Counties in small towns with few public schools were not included in this study. Three public schools were randomly selected in each area, including one primary school (class 5-6) and two secondary schools (classes 7 to 12) by age group (11-18 years) and two or three classes were randomly selected in each class. Normally, there were 50 students in each classroom. We randomly selected 30 students with an equal number of boys and girls aged 11 to 18 in each selected class using a prepared list of random numbers. A total of 2,700 students from 15 public schools were selected to be enrolled. All participants and their parents were informed of the content and objectives of this study. A questionnaire containing the CBCL, the YSR and questions related to the child, parents and family was distributed to 2,700 participants after the written agreement of the survey participants. Of the 2,426 questionnaires returned, 227 subjects were excluded due to false information or a lack of data.

The final courses consisted of 2,199 Chinese youth attending school (921 boys and 1,278 girls). In our population, the average age was 13.0 years (SD – 2.3, range 11-18 years). Among youth families, 32.3%, 47.3% and 20.4% had low, medium and high socio-economic status (SES). In our population, SES were indicated by the highest level of education of parents, similar to the study of wines et al. (1995). The level of education was divided into three groups: the high school level, the higher level and the higher or higher level. The effective response rate was 81.4%. The procedures used were in accordance with the ethical standards of the Human Experimentation Committee of the University of Medicine of China. Teenagers are in one of the most difficult times of their lives, and unfortunately parents have to deal with the worst, but there are things you can do to minimize the damage to your long-term relationship.

It should be noted that the agreement between paternal and teacher assessments for behaviour, hyperactivity and overall difficulties was lower than that between the evaluations of mothers and teachers on these scales (p < 0.001). The correlations between the evaluations of mothers and teachers were closer to the parents – teacher correlations reported in the journal Stone [11]. In contrast, father and teacher evaluations were significantly lower (p < 0.001) than the correlations reported in the journal [11] (0.26-0.47), with the exception of peer problems and prosocial scale. In addition, in our study, correlations between maternal and teacher evaluations were predominantly higher (p <.001) or equal to the metaanalytic average of 0.27 [5], while correlations between father and teacher evaluations were predominantly lower (p < 0.001) or equal to the metaanalytic average [5]. This is not so surprising, as much of the research on young children uses mothers as informants [52-54]. For example, most instruments for mothers have been developed and standardized, which has sometimes led to problems using the instrument with fathers [52-54]. Slightly lower correlations between father and teacher relative to father and teacher assessments are consistent with the results of a previous study on the consistency of behavioural problems in young children between rats, which showed higher correlations (r -0.19) when the data were analyzed without fathers than with fathers (r – 0.17).