Kanaya Dyara Taqiiya
Vrije Universiteit Amsterdam
2763481
Cristhian Martínez Moreno
Group 9
Measurement Theory & Assessment 1
4 April 2023
, THE RELIABILITY AND VALIDITY OF THE SDQ 1
The Reliability and Validity of the SDQ
The Strength and Difficulties Questionnaire (SDQ) is used to analyse the mental
health and emotional well-being of children between the ages of 4 and 17. The SDQ consists
of 25 questions divided into 5 sub-sections assessing the following: emotional symptoms,
conduct problems, hyperactivity/inattention, peer relationship problems and prosocial
behaviour. The questionnaire is to be completed by the parents or teachers of the respective
children. This study focuses on the total problem scale, the Hyperactivity subscale and the
Prosocial behaviour subscale. The total problem scale is based on all items except the
Prosocial behaviour subscale. This allows a better understanding of the emotional and
behavioural needs of the child in order to provide them with the relevant assistance required.
The Hyperactivity subscale measures the child’s level of hyperactivity and inattention, and
the Prosocial behaviour subscale measures the child’s ability to connect well with peers. Of
all the subscales, the Prosocial behaviour subscale is the only strength-based measure
(Goodman, 1997).
As the SDQ covers a broad range of mental health symptoms, it is one of the most
preferred tools in clinical practice and research. The SDQ has been shown to be a sufficient
tool in assisting attention deficit hyperactivity disorder (ADHD) diagnoses (Hall et al., 2019).
Furthermore, the SDQ has been shown to be able to predict simultaneous symptoms of
anxiety and depression in children, which eliminates the need for other tools that are
restricted to clinical use, such as the Revised Child Anxiety and Depression Scale (RCADS)
(Bryant et al., 2020).
This study aims to investigate both the reliability and validity of this questionnaire.
Reliability refers to the degree to which the results of the questionnaire can be said to be
accurate. Furthermore, validity refers to the degree to which the questionnaire measures what
it aims to measure. This is necessary because an incorrect diagnosis requiring any associated
medication can negatively affect an individual’s quality of life. Past research has shown the
SDQ to have an acceptable internal consistency and test-retest reliability, concluding that it
has acceptable reliability (Muris et al., 2003). Internal consistency refers to the extent to
which items within an instrument measure various aspects of the same construct (Revicki,
2014), and test-retest reliability is obtained by doing the questionnaire twice over a period of
time on an individual.