Reliability and Validity of SDQ in Nigerian Population

This research investigates the current reliability and validity of SDQ (Strengths and Difficulties Questionnaire) through Nigerian population. The report highlights the importance of mental health of children and adolescents and how SDQ can be used to capture their perspectives.

University
*** Semester
Individual Differences
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Abstract
The spot light of this research is mental health of children, where SDQ’s current reliability and
validity is researched, based on the Nigerian population. This research uses SDQ (Strengths and
Difficulties Questionnaire), which refers to an evaluation related screening questionnaire that
draws the emotional and behavioural screening, on child mental health. The disorders in children
and adolescents is a growing public health concern. SDQ can be used by children and youngsters
easily, as it helps in capturing their perspectives. Thus, this report is regarding mental health of
children and SDQ is the most widely used method. With the help of SDQ, I will be investigating
the current reliability and validity of scale through Nigerian population. Moreover, as SDQ
facilitates with data measures that are translated in various languages, I have opted this method.
My statistical technique, Exploratory Factor Analysis (EFA) is represented. Totally, 7019
participants from Nigeria have participated, whose age ranges between 4 to 17 years. My internal
consistency analysis is represented. Hence, the research ensures to highlight the main findings.
Subsequently, it is concluded that the reliability and validity of the sample is quite good.
Keywords: Adolescence; Child mental health; EFA; Nigeria; SDQ
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Table of Contents
1. Introduction............................................................................................................................................................ 1
1.1 Aim..................................................................................................................................................................... 2
1.2 Objective............................................................................................................................................................. 2
2. Literature Review.................................................................................................................................................... 2
3. Methods.................................................................................................................................................................. 3
3.1 Data.................................................................................................................................................................... 3
3.2 Measures............................................................................................................................................................. 3
3.3 Statistical Analysis.............................................................................................................................................. 4
4. Results..................................................................................................................................................................... 5
5. Discussion................................................................................................................................................................ 7
5.1 Limitation........................................................................................................................................................... 8
5.2 Recommendation................................................................................................................................................ 8
References........................................................................................................................................................................ 9
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1. Introduction
This research is related to mental health of children, where SDQ’s current reliability and
validity is researched, based on the Nigerian population. This research ensures to find the
importance of, mental health of children. This research utilizes SDQ (Strengths and Difficulties
Questionnaire). This research is important because, it is important to identify the psychopathy in
children and adolescents early, by assessing their behaviour, as this will help to provide medical
help. Moreover, the mental health issues in the children and the adolescents can turn out to be a
major burden and on the other hand, it can even have the child’s family, school and community.
Strengths and Difficulties Questionnaire refers to an evaluation related screening questionnaire
that draws the emotional and behavioural screening, on child mental health. The disorders in
children and adolescents is a growing public health concern and SDQ can be utilized by children
and youngsters easily to capturing their perspectives. Thus, this report is regarding mental health
of children and SDQ is the most widely used method ("Strengths and Difficulties Questionnaire",
2017). With the help of SDQ, I will be investigating the current reliability and validity of scale
through Nigerian population. Moreover, as SDQ facilitates with data measures that are translated
in various languages, so I have opted this method to discard the cultural differences and help
with the translation issues. The Exploratory Factor Analysis (EFA) is used in this study, to
analyze the data. As, EFA helps to decrease the data to an extremely smaller set of summary
variables and also helps in exploring the phenomena’s underlying theoretical structure. It is also
used to for identifying the relationship structure among the variable and respondent
("Exploratory Factor Analysis", 2018).
In the world, there in increasing number of children and adolescents, who are identified
to suffer from various mental health issues, which will have greater impact of the lives of the
children and this need to be addressed soon, where the parents and teachers must be made aware
of such children’s emotional functioning. Because, this increases these children’s strength and
eases them to handle their difficulties ("Children and young people", 2018). However, such
children needs immediate help (Tracy, 2016). From the research of Du, Kou & Coghill, in China,
it is observed that SDQ is quite reliable and valid to be used on populations outside of Britain
(Du, Kou & Coghill, 2008). But still, there are a lot of questions which clearly direct that,
whether SDQ has got reliability and validity in various samples or not.
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1.1 Aim
To understand the reliability and validity of SDQ in various samples.
1.2 Objective
The objective of this research is to investigate the SDQ’s reliability and validity in
various samples. The child mental health issues in Nigerian population will be investigated.
2. Literature Review
According to (Du, Kou & Coghill, 2008), the Chinese data was analyzed to diagnose the
psychometric characteristics of Strengths and Difficulties Questionnaire in the children. Callous
Unemotional (CU) was the trait that was pointed to be identified in the early childhood. This
study talks about the environmental risk factors, early signs and longitudinal trajectories and
treatments. The research findings showed mixed findings, when it comes to the psychometric
properties of the Chinese translation of SDQ. The reliability is been a concern related to Peer
Problems and self-ratings by the adolescents. However, there is a good support for meeting
validity, but for structural validity, just partial support is given. Additionally, it is possible to
solve certain issues with carefully examination of wording and current questions’ meanings.
As per (Hawes & Dadds, 2004), the Australian psychometric properties of the Strengths
and Difficulties Questionnaire (SQD) are examined. The behavioural and emotional issues in
children and adolescents are researched. With the help of a large community sample (n = 1359)
of young Australian children aged between 4 to 9 years, the internal consistency, stability, and
external validity of the parent-report SDQ was assessed. It helped to produce the normative data
and cut-offs. It even exhibited the moderate to strong internal reliability. Moreover, it evidenced
the adequate validity in the relationship of these scales, in association between the SDQ
subscales, teacher ratings and the diagnostic interviews. The SDQ total difficulties scores were
linked with the status of the concurrent treatment and the stability score of 12 months. Hence,
this study shows the evidence of SDQ showing the Psychometric Properties in the Australian
data.
Even the study of (Koskelainen, Sourander & Kaljonen, 2000), showed satisfying
psychometric properties and was considered to suit to assess the emotional and behavioural
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problems in the Greek adolescents. Where, it aimed to assess the Greek version of the SDQ’
reliability and validity. The adolescents aged between 11 to 17 years were considered, which
had 1194 Greek samples. The Cronbach α coefficient’s calculation was used to determine the
internal consistency reliability. The factor structure of the questionnaire was tested by
conducting Varimax Orthogonal Transformation. Next, the validity was examined, with the
investigation of the correlation of the SDQ with the KIDSCREEN questionnaire and its
association with demographic factors. The internal consistency reliability was acceptable with a
Cronbach α above 0.70 for all SDQ scales except for conduct and peer problems. Inter-rater
correlations ranged from 0.33 to 0.45. Test-retest stability was good (ICCs > 0.60). Correlation
coefficients between the SDQ and KIDSCREEN questionnaire were significant. For all of the
SDQ scale mean scores, the small effect sizes (d > 0.5) were identified. The results showed
satisfying psychometric properties and was considered to suit to assess the emotional and
behavioural problems in the Greek adolescents.
3. Methods
3.1 Data
The participants are the children and adolescents from Nigeria, where the investigation
was conducted to assess the prevalence of psychological disorders. The age ranges between 4 to
17 years, where the mean and standard mean are represented.
3.2 Measures
Different types of reliability and validity of SDQ are discussed. For instance, from the
study of Hawes and Dadds, where the Australian psychometric properties of the Strengths and
Difficulties Questionnaire (SQD) were examined. The behavioural and emotional issues in
children and adolescents were researched. With the help of a large community sample (n = 1359)
of young Australian children aged between 4 to 9 years, the internal consistency, stability, and
external validity of the parent-report SDQ was assessed. It helped to produce the normative data
and cut-offs. It even exhibited the moderate to strong internal reliability. Moreover, it evidenced
the adequate validity in the relationship of these scales, in association between the SDQ
subscales, teacher ratings and the diagnostic interviews. The SDQ total difficulties scores were
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linked with the status of the concurrent treatment and the stability score of 12 months. Hence,
this study shows the evidence of SDQ showing the Psychometric Properties in the Australian
data.
The research of (Koskelainen, Sourander & Kaljonen, 2000), aimed to assess Greek
version of the SDQ’ reliability and validity. The adolescents aged between 11 to 17 years were
considered, which had 1194 Greek samples. The Cronbach α coefficient’s calculation was used
to determine the internal consistency reliability. The factor structure of the questionnaire was
tested by conducting Varimax Orthogonal Transformation. Next, the validity was examined, with
the investigation of the correlation of the SDQ with the KIDSCREEN questionnaire and its
association with demographic factors. The internal consistency reliability was acceptable with a
Cronbach α above 0.70 for all SDQ scales except for conduct and peer problems. Inter-rater
correlations ranged from 0.33 to 0.45. Test-retest stability was good (ICCs > 0.60). Correlation
coefficients between the SDQ and KIDSCREEN questionnaire were significant. For all of the
SDQ scale mean scores, the small effect sizes (d > 0.5) were identified. The results showed
satisfying psychometric properties and was considered to suit to assess the emotional and
behavioural problems in the Greek adolescents.
The SDQ comes in different versions like, Greek version. The SDQ is 25-item of child
behavioural screening. The subscales are mentioned. The measure is constructed to measure four
components of behavioural difficulty such as, the emotional symptoms, peer relationship,
conduct problems and hyperactivity. Whereas, the strength component is calculated. The SDQ is
widely used, as it facilitates with data measures that are translated in various languages, which
helps to discard the cultural differences and resolves the translation issues.
3.3 Statistical Analysis
The data was screened for normality. For instance, skewness, kurtosis, and vodka tests,
then descriptive statistics was requested. The means and standard deviations, followed by
estimates of internal consistency for relevant subscales.
The internal consistency is estimated. The factor analysis states that, EFA is used to
analyze the data. As, EFA helps to decrease the data to an extremely smaller set of summary
variables and also helps in exploring the phenomena’s underlying theoretical structure. It is also
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used to for identifying the relationship structure among the variable and respondent
("Exploratory Factor Analysis", 2018).
The principle axis factoring is used as it not only helps with correlations, but it also helps
to identify the covariances and other SSCP measures.
4. Results
For the SDQ subscales, the descriptives are tabulated. The internal consistency was
calculated with a pre-determined value, required for reliability. The SDQ subscales equal to α =
0.54, which denotes lowest peer relationship. Problem (α =0.63), Emotional Symptoms (α
=0.67), Prosocial Behavior (α =0.65) and Hyperactivity (α =0.76). The internal consistency for
the SDQ is α = 0.75. The below table represents the values of, Cronbach‘s alphas value, Standard
Deviation, acceptable.Details of Mean and Skewness ,Kurtosis.
Table 1
Means, Standard Deviations, Skewness, Kurtosis, and Internal Consistency (α) Scores for SDQ
Subscales.
Scale M SD Skewnes
s
Kurtosis Cronbac
h alpha
(α)
Conduct Problems 6.47 1.70 1.56 2.86 0.63
Emotional
Symptoms
6.84 1.98 1.32 1.61 0.67
Prosocial Behaviour 13.83 1.58 -1.81 4.14 0.65
Hyperactivity 8.20 2.61 0.73 -0.20 0.76
Peer Relationships 6.38 1.62 1.61 3.04 0.54
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Table 2
Structure Matrix Table
Factors SDQ
Items
Factor Loading
Conduct
Problems
5
5
10
13
21
.523
.511
.523
.581
.400
Emotional
Symptoms
4
9
11
13
22
.374
.631
.581
.580
.631
Prosocial
Behaviour
1
3
6
16
21
.564
.480
.587
.523
.565
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Hyperactivity 3
9
12
20
22
-.621
-.610
-.744
-.575
-.671
Peer
Relationships
6
10
13
18
21
.463
.465
.612
.480
.423
Factor Correlation Matrix
Facto
r 1 2 3 4 5
1 1.000 .250 -.271 -.443 .311
2 .251 1.000 -.106 -.362 .468
3 -.271 -.108 1.00
0
.327 -.253
4 -.443 -.363 .328 1.000 -.293
5 .311 .467 -.253 -.293 1.000
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5. Discussion
The findings of this research is represented. When compared to the findings present in
the introductory part of this research, to show the final findings. The similarities are, listed along
with the differences, by using the psychological theory. Hence, this research has met its
objective, to investigate the SDQ’s reliability and validity in various samples, where the child
mental health issues in Nigerian population are investigated. Thus, this research aims to find the
importance of, mental health of children in Nigeria, which is not accurate due to the following
limitations.
5.1 Limitation
The following are the limitation of this study:
1) It was difficult to get the information related to Nigerian population, to
determine the child mental health.
2) Apart from the access of original data, the language barrier is the major
concern.
3) The secondary data is inaccurate.
4) The participants find it really difficult to understand and answer the questions
specified in English.
5) The age group considered for the study increased the difficulty, as the children
of age group 4 to 7 years were unable to understand and answer the questions.
6) It was also difficult to interact with them, due to lack of cooperation.
7) This increased the complexity of reporting the accurate results, in the following
report.
5.2 Recommendation
The future recommendations includes, to avoid secondary data and hence the original
data is highly recommended, as it provides accurate answers. On the other hand, the language
barrier must be discarded with effective tool. It is better to take help from the parents to
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overcome the cooperation and understanding issues in the children of age group 4 to 7 year old.
References
Children and young people. (2018). Retrieved from
https://www.mentalhealth.org.uk/a-to-z/c/children-and-young-people
Du, Y., Kou, J., & Coghill, D. (2008). The validity, reliability and normative scores of the
parent, teacher and self report versions of the Strengths and Difficulties Questionnaire in
China. Child And Adolescent Psychiatry And Mental Health, 2(1), 8. doi: 10.1186/1753-
2000-2-8
Exploratory Factor Analysis. (2018). Retrieved from https://www.statisticssolutions.com/factor-
analysis-sem-exploratory-factor-analysis/
Hawes, D., & Dadds, M. (2004). Australian data and psychometric properties of the Strengths
and Difficulties Questionnaire. Australian And New Zealand Journal Of Psychiatry, 38(8),
644-651. doi: 10.1111/j.1440-1614.2004.01427.x
Koskelainen, M., Sourander, A., & Kaljonen, A. (2000). The Strengths and Difficulties
Questionnaire among Finnish school-aged children and adolescents. European Child &
Adolescent Psychiatry, 9(4), 277-284. doi: 10.1007/s007870070031
Strengths and Difficulties Questionnaire. (2017). Retrieved from
https://www.corc.uk.net/outcome-experience-measures/strengths-and-difficulties-
questionnaire/
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Tracy, N. (2016). Psychopathic Children, Psychopathic Behavior in Children. Retrieved from
https://www.healthyplace.com/personality-disorders/psychopath/psychopathic-children-
psychopathic-behavior-in-children
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