Paula Greally1, Ian Kelleher2, Jennifer Murphy2, Mary Cannon2

Author affiliations
1RCSI medical student
2Department of Psychiatry, Education and Research Centre, Beaumont Hospital, Dublin

Royal College of Surgeons in Ireland Student Medical Journal 2010; 3: 33-35.

Aim: This study aims to assess a community of Irish adolescents using the Strengths and Difficulties Questionnaire (SDQ) for behavioural difficulties and mental health disorders.
Method: All fifth and sixth class pupils attending eight primary schools were eligible to participate. The self-report version of the SDQ was administered to the pupils in the classroom.
Results: Thirty participants (8.7%) had an abnormal SDQ score and 53 (15.3%) had a borderline abnormal SDQ score. Abnormal SDQ scores were more common among females (9.7%; mean score = 11.86; sd = 5.4) than among males (7.6%; mean score = 10.96; sd = 5.26). The difference was most pronounced on the emotional symptoms subscale (females received a mean score of 4.03 [sd = 2.1] compared to a mean male score of 2.90 [sd = 2.1]).
Conclusions: Mental health problems are widespread among Irish adolescents. The SDQ is a useful preliminary assessment tool of the mental health profile of Irish adolescents and highlights the need for childhood mental health promotion in schools. The SDQ could also be used in a primary care setting to screen adolescents for mental disorders.
Key words: Psychiatry, behaviour, mental disorders, adolescence, questionnaires, schools, Ireland.

Adolescence is a period of physical, psychological, emotional and personality change, which can lead to stress, and emotional and behavioural problems. Studies have shown that there is a 10% overall prevalence of mental disorders among five- to 15-year-olds and this figure may be as high as 25% among children and adolescents who attend primary care services in the UK.1 Standardised assessment of mental health difficulties in a primary care setting is commonplace in the US; however, this practice is not prevalent in Ireland.2
The Strengths and Difficulties Questionnaire (SDQ) (Goodman, 1997)3 is a useful tool that could be applied in a community setting to assess emotional and behavioural problems.2 It has been found to effectively predict the presence of conduct, hyperactivity, emotional, and psychiatric disorders.4 Previously, it has been used in Britain to screen a community cohort for child psychiatric disorders and it identified over 70% of individuals with conduct, hyperactivity, depressive and some anxiety disorders.5
Numerous studies have been conducted to examine the rates of psychiatric disorders among young people worldwide,6,7 and these describe an increase in particular psychiatric disorders, such as conduct and emotional problems.8 There is little epidemiological data on the prevalence of psychiatric disorders among Irish adolescents, although data will soon be available from the national longitudinal study ‘Growing Up in Ireland’. Prior to this, Dr Fionnuala Lynch of the Mater Misericordiae Hospital in Dublin and Professor Carol Fitzpatrick of University College Dublin conducted an epidemiological investigation of mental health problems among Dublin adolescents aged 12 to 15 years.9 In this project we propose to assess a community of Irish adolescents, using the SDQ for behavioural difficulties and mental health disorders.

The study population
The study was carried out in Maynooth, Lucan, Leixlip, Celbridge, Carragh and Dunboyne, in Ireland. The study population consisted of fifth and sixth class pupils attending eight primary schools in these towns, aged between 10 and 13 years.

The Strengths and Difficulties Questionnaire
The SDQ is a user-friendly screening questionnaire, which can be used to assess behavioural problems and mental health disorders. It can be administered to the parents and teachers of four- to 16- year-olds and to the 11- to 16-year-olds themselves. Goodman, Ford, Simmons, Gatward and Meltzer reported the scale’s internal reliability to be acceptable, with a Cronbach alpha coefficient of 0.73.5,10 The questionnaire consists of 25 questions subdivided into five categories: conduct; hyperactivity; peer problems; emotional; and, prosocial, with five questions in each scale. A sample item from the SDQ is: “I am restless, I cannot stay still for long”. The participant chooses between three boxes and ticks their response. The boxes are labelled “not true”, “somewhat true” or “certainly true”.
Each of the categories is given a score and then summed to get a total difficulties score, except the prosocial score, which is assigned a separate score. The scores can then be used to make separate predictions for conduct–oppositional disorders, hyperactivity–inattention disorders, and anxiety–depressive disorders.

The screening procedure
After obtaining approval from the Beaumont Hospital Ethics Committee, permission was sought from the principals of each of the selected schools to recruit students for the study. An information sheet and consent form was sent to each parent. The consent form was to be signed by a parent or guardian and returned to the school. The questionnaires were distributed to the pupils as a group in their classrooms during a pre-arranged time.
Each pupil who had returned a consent form was given a copy of the questionnaire for completion. The pupils were asked to read the questionnaire and answer it to the best of their ability. Every effort was made to ensure that the pupils had privacy when completing the questionnaire. Researchers were available to answer any of the pupils’ questions or to clarify instructions. The pupils were also asked to include their name, class and age.

Statistical analysis
Data were analysed using the Statistical Package for the Social Sciences (SPSS) and established cut-off scores indicated high risk for mental health problems.11

A group of 346 pupils aged 10 to 13 years, which consisted of 171 boys and 175 girls attending the eight participating schools, participated in the screening study. The mean age of the study population was 11.57 years. Thirty participants (8.7%) received an abnormal SDQ score. A further 53 (15.3%) received a borderline abnormal SDQ score. Abnormal and borderline abnormal scores are shown in Table 1.
The most common abnormal scores were on the hyperactivity and conduct problems subscales (13.6% had abnormal scores on each of these subscales). A total of 2.9% of the population tested had abnormal scores on the emotional symptoms subscale versus 2.3% on the peer problems subscale. Only 0.3% of the total population scored abnormally on the prosocial subscale.

Sex differences
Abnormal SDQ scores were more common among females (9.7%; mean score = 11.86; sd = 5.4) than among males (7.6%; mean score = 10.96; sd = 5.26). The difference was most pronounced on the emotional symptoms subscale, with females receiving a mean score of 4.03 (sd = 2.1) compared to a mean male score of 2.9 (sd = 2.1). Males, however, had higher (more abnormal) mean scores on the conduct problems subscale (2.72 vs. 2.13 mean female score), as well as lower (more abnormal) mean scores on the prosocial behaviour subscale (7.85 vs. 8.78 mean female score).

Table 1: SDQ scoring values.

Total difficulties score0-1516-1920-40
Emotional symptoms score0-567-10
Conduct problems score0-345-10
Hyperactivity score0-567-10
Peer problems score0-456-10
Prosocial behaviour score6-1050-4

The main objective of this study was to provide a generalised assessment of Irish adolescents aged 10 to 13 years using the SDQ.
This study showed that 8.7% of the participants studied had an abnormal SDQ score, which would suggest that they were likely to suffer from some degree of mental health issues. Of these participants, 9.7% were female and 7.6% were male. Normative data has not been published for Ireland but has been published in Britain (n=4,228). Some 5.2% of British males and 5.1% of British females aged 11-15 received abnormal scores on the SDQ.5 This would indicate that the Irish participants were perhaps more at risk of developing mental health difficulties than their British counterparts. However, socio-economic differences and the fact that the British study had a bigger cohort would have to be taken into account when comparing these two groups.
SDQs are a useful tool to identify participants who may have emotional problems (females more than males in this study) and conduct problems (males more than females in this study). However, it has been shown that, on the whole, SDQs completed by parents and teachers are better indicators than SDQs completed by adolescents themselves.5
The socio-economic class of the participants is not known, nor is the population norm of the geographical area. Prior research indicates that respondents to questionnaires and those who agree to participate in research tend to be of a higher social class.12 As a consequence, there could have been an under- or over- representation of psychopathology in the study sample.
This was a school-based sample. Children may not legally leave school in Ireland until the age of 16; however, some may not attend until that age. Among those registered with the school, a number will be absent on any one day. The dropouts and absent adolescents are likely to be from a vulnerable section of society and have potentially high levels of emotional and behavioural problems.13,14 Additionally, the schools who participated in the study were all mainstream schools and special schools for those who have intellectual and physical disabilities were not included. Students in these settings are known to have higher rates of emotional and behavioural problems when compared to the general population.15 As a consequence, the prevalence rates indicated in this study are liable to be an inaccurate estimate of the true prevalence of psychiatric disorders in young adolescents in the community.

Mental health problems are common among the general adolescent population in Ireland. Early intervention should be a focus of health policy; however, more resources are necessary if childhood mental health problems are to be addressed. From the analysis of all the data and results it can be concluded that the SDQ gives a practical assessment of the mental health profile of young Irish adolescents. It is a short, simple questionnaire, which could be utilised in a general practice setting to screen adolescents for mental distresses.

I wish to acknowledge financial support from the Royal College of Surgeons in Ireland 2009 Alumni Student Research Fund in General Practice.


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