The GHQ is a well-known instrument for measuring minor psychological distress and has been translated into a variety of languages [11–16]. However, it is not a tool for indicating a specific diagnosis. This study reports data from a validation study of the 12-item GHQ in Iran. In general, the findings showed promising results and were comparable with most research findings throughout the world. Our two-factor solution was similar to those reported in the WHO study of psychological disorders in general health care . Reliability was assessed by internal consistency of the questionnaire reporting Cronbach's alpha coefficient and validity was examined by convergent validity performing correlation between the GHQ-12 and global quality of life scores and both showed satisfactory results.
It is argued that although the GHQ-12 was originally developed as a unitary screening measure for psychological problems, there have also been efforts to identify whether it has a multidimensional structure . The World Health Organization study of psychological disorders in general health care in 15 different centers indicated that for the GHQ-12 substantial factor variation between centers exist. However, the study reported that after rotation two factors expressing depression and social dysfunction could be identified . The findings from present study showed that the Iranian GHQ-12 is a valid measure of psychological distress and the factor structure of the questionnaire was very similar to that of the original language. Interestingly a recent findings from a Japanese study reported that the GHQ-12 could be used as an internally reliable and homogenous scale that produces mainly the factors of psychological distress and social dysfunction .
We used the bi-modal fashion of scoring and the results indicated that this method in Iran appears to be useful. Evidence suggests that there is no tendency for the GHQ to work less efficiently in developing countries . The mean GHQ-12 score in this study was 3.7 (SD = 3.5). It is recommended that the mean GHQ score for the whole population of respondents provides a rough guide to the best cut-off threshold . Thus considering people who scored above the mean, the findings from the present study indicated that 44% of the respondents showed an indication of mental health problems . This clearly suggests that if investigators wish to use a screening instrument as a case detector, the shorter GHQ is remarkably robust and works as well as the longer instrument . Similar studies among young adolescents reported that the GHQ-12 is a particularly useful measure with adolescents where there are likely to be a number of different threats to their psychological health, such as poor self-esteem, that may not necessarily constitute a formal psychiatric condition . In contrast, studies have shown that the GHQ-12 is not a suitable instrument for some special populations such as elderly patients .
Iran has a very young population. In general, the findings from this study indicated that mental health in young people in Iran is poor and it is strongly associated with their quality of life. Since mental health in young adolescents could be regarded as a risk factor for psychological disorders such as antisocial behavior, criminal activity, suicidal behavior, substance abuse, depression, and eating disorders , improving quality of life in this age group becomes very important task. However, in interpreting the study findings it should be noted that the young people in the sample were a selected sample and thus it cannot be generalized to the whole population of young adolescents in Iran.