Strengths and Difficulties Questionnaire (SDQ)

Abstract

The Strengths and Difficulties Questionnaire (SDQ) is a widely used, brief 25-item behavioral screening instrument designed for children and adolescents aged 3 to 16 years. Developed by Robert Goodman, the SDQ assesses both psychological difficulties and positive attributes. The instrument is divided into five scales: four measuring difficulties (emotional symptoms, conduct problems, hyperactivity/inattention, and peer relationship problems) and one measuring strengths (prosocial behavior). The SDQ is notable for its versatility, offering parent, teacher, and self-report versions, and is used globally for screening, research, and outcome measurement in clinical and community settings.

Keywords

Strengths and Difficulties Questionnaire (SDQ), Child mental health, Behavioral screening, Prosocial behavior, Hyperactivity, Emotional symptoms, Conduct problems, Psychometric properties

Authors

Robert Goodman

Purpose

The primary purpose of the SDQ is to serve as a concise screening tool for common mental health and behavioral problems in children and adolescents. Its design, emphasizing brevity and multi-informant administration (parent, teacher, and adolescent self-report), facilitates its use in large-scale epidemiological studies, routine clinical practice, and educational settings.

Beyond simple screening, the SDQ is also valued as an outcome measure, particularly in assessing the effectiveness of interventions. An extended version of the instrument is available specifically to evaluate the impact of difficulties, covering aspects such as chronicity, distress, social impairment, and burden on others (Goodman & Scott, 1999). Furthermore, a version exists that includes additional questions to measure the impact of specific interventions, proving useful in contexts like Australian Child and Adolescent Mental Health Services (CAMHS) (Mathai, Anderson & Bourne, 2003).

Construct

The SDQ measures five distinct scales, each comprising five items, reflecting both internalizing and externalizing dimensions of child behavior. The four difficulty scales are aggregated to form a Total Difficulties Score. The inclusion of a positive scale (Prosocial Behavior) distinguishes the SDQ from many traditional deficit-focused instruments.

• Emotional Symptoms: Measures internalizing problems such as worries, somatic complaints, and anxiety.
• Conduct Problems: Measures externalizing, rule-breaking behaviors and defiance.
• Hyperactivity/Inattention: Measures concentration difficulties, restlessness, and impulsivity.
• Peer Relationship Problems: Measures difficulties in social interactions, loneliness, and being picked on.
• Prosocial Behavior: Measures positive behaviors such as helpfulness, kindness, and sharing.

The conceptual basis for these scales stems from a factor analysis conducted on an expanded iteration of the Rutter Parent Questionnaire (Elander & Rutter, 1996; Goodman, 2004). Goodman specifically aimed to create a measure that reflected contemporary concerns, including concentration and prosocial behavior, while maintaining practicality with a one-page format.

Validity

The SDQ is generally considered to possess acceptable validity across various populations. Initial validation demonstrated good concurrent validity when tested against the Rutter Parent Questionnaire. Comparative studies have shown the SDQ to be superior to the Child Behaviour Checklist (CBCL) in identifying inattention and hyperactivity, while performing comparably in detecting overall internalizing and externalizing problems (Goodman & Scott, 1999).

Furthermore, SDQ assessments correlate moderately to highly with clinical diagnoses derived from both community and clinical samples (Mellor, 2005). However, a systematic review of the psychometric properties of the SDQ (Kersten et al., 2016) concluded that while the scale is appropriate for comparing groups in research settings, it may lack the necessary sensitivity required for definitive clinical decision making regarding individual diagnoses. The discriminant ability of the parent and teacher versions is notably stronger when used in clinical samples compared to community samples (Stone et al., 2010).

Reliability

The SDQ demonstrates varying levels of internal consistency depending on the scale and the informant. The teacher version generally exhibits high internal consistency, with Cronbach’s alpha coefficients ranging from 0.70 for the Peer Problems scale to 0.88 for the Hyperactivity/Inattention scale (Goodman, 2001).

Reliability for the parent-rated scales is slightly more variable, ranging from 0.57 for the Peer Problems and Prosocial Behavior scales up to 0.84 for the Hyperactivity/Inattention scale (Goodman, 2001). A persistent limitation noted in the literature is the low agreement observed between different informants (parents and teachers), with correlations typically ranging from 0.24 to 0.45 (Kersten et al., 2016). This discrepancy highlights the importance of utilizing a multi-informant approach when administering the SDQ.

Factor Analysis

The structure of the SDQ, comprising five subscales, was derived through factor analysis. This analysis was conducted on an expanded version of the Rutter Parent Questionnaire (Elander & Rutter, 1996), which included additional items pertaining to strengths and contemporary concerns (Goodman, 2004). The resulting five-factor structure provides a clear differentiation between specific areas of difficulty and the single domain of prosocial strength.

Instrument

Test Type: Screening Questionnaire; Multi-Informant Measure

Format: 25 items scored on a 3-point ordinal scale (0=not true, 1=somewhat true, 2=certainly true). The instrument is designed to be one page in length.

Language Available: Available in over 60 languages, including Auslan (Cornes & Broqn, 2015). Scoring templates and computerized scoring are available from the SDQ website: www.sdq.org.

Population Group: Children and Adolescents.

Age Group: 3–16 years.

Population Details: The SDQ utilizes parent and teacher reports for younger children, and self-report measures for adolescents (11–16 years). Norms are widely available, including specific Australian norms, with recent development focusing on children aged 4 to 6 years (Kremer et al., 2015). Research has supported its appropriateness for diverse groups, such as Aboriginal children in urban environments, though item wording improvement was suggested (Williamson et al., 2014).

Test Methodology: Informants base their ratings on the child’s behavior over the past six months. Scores for the four difficulty scales are summed to generate a Total Difficulties Score. Interpretation categorizes the child into one of three ranges based on percentile scores: normal (< 80th percentile), borderline (80th–90th percentile), or clinically significant (> 90th percentile).

Keywords

Child behavioral assessment, Robert Goodman, Developmental psychology, Multi-informant, Screening tool, Clinical cut-offs, Total difficulties score, Internalizing problems, Externalizing problems

Authors

Author ORCID Identifier: N/A (Not provided in source content)

Affiliation Email addresses: N/A (Not provided in source content)

Correspondence Address: N/A (Not provided in source content)

Permissions & Fee and Test Year

The SDQ is generally available for use without charge for non-commercial research and clinical purposes, though specific licensing may apply depending on the jurisdiction and version used. The instrument was initially developed by Robert Goodman in the United Kingdom, with the seminal research note published in 1997 (Goodman, 1997).

Reference’s

• Cornes, A. J. & Broqn, M. P. (2012). Mental health of Australian deaf adolescents: An investigation using an Auslan version of the strengths and difficulties questionnaire, Deafness and Educational International, 14, 161- 175.
• Elander, J., & Rutter, M. (1996). Use and development of the Rutter Parents’ and Teachers’ Scales. International Journal of Methods in Psychiatric Research, 6, 63-78.
• Goodman, R. (1994). A modified version of the Rutter parent questionnaire including items on children’s strengths: A research note. Journal of Child Psychology and Psychiatry, 35, 1483-1494.
• Goodman R (1997) The Strengths and Difficulties Questionnaire: A Research Note. Journal of Child Psychology and Psychiatry, 38, 581-586.
• Goodman, R. (1999). The extended version of the Strengths and Difficulties Questionnaire as a guide to child psychiatric caseness and consequent burden. Journal of Child Psychology and Psychiatry and Allied Disciplines, 40(5), 791–799.
• Goodman, R. (2001). Psychometric properties of the strengths and difficulties questionnaire. Journal of The American Academy of Child and Adolescent Psychiatry, 40(11), 1337–1345.
• Goodman, R., Meltzer, H., & Bailey, V. (1998). The Strengths and Difficulties Questionnaire: A pilot study on the validity of the self-report version. European Child & Adolescent Psychiatry, 7(3), 125–130.
• Kersten, P., Czuba, K., Mc Pherson. K., Dudley, M., Elder, H., Tauroa, R. & Vandal, A. (2016). A systematic review of evidence for the psychometric properties of the Strengths and Difficulties Questionnaire, International Jounral of Behavioral Development, 40, 64-75.
• Kremer, P., De Silva, A., Cleary, J., Santoro, G., Weston, K., Steele, E. Nolan, T. & Waters, E. (2015). Normative data for the Strengths and Difficulties Questionnaire for young children in Australia, Journal of Peadiatrics and Child Health, 51, 970-975.
• Mathai, J., Anderson, P., & Bourne, A. (2003). Use of the Strengths and Difficulties Questionnaire as an outcome measure in a child and adolescent mental health service. Australasian Psychiatry, 11(3), 334–337.
• Mellor, D. (2005). Normative data for the strengths and difficulties questionnaire in Australia. Australian Psychologist. 40, 215–22.
• Stone, L.L., Otten, R., Engels, R., Vermulst, A.A., Janssens, J.M. (2010) Psychometric properties of the parent and teacher versions of the strengths and difficulties questionnaire for 4-to 12-year-olds: a review. Clinical child and family psychology review 13: 254–274. doi: 10.1007/s10567-010-0071-2.
• Williamson, A., McElduff, P., Dadds, M., D’Este, C., Redman, S., Raphael, B., Daniels, J. & Eades, S. (2014). The construct validity of the Strengths and Difficulties Questionnaire for Aboriginal children living in urban New South Wales Australia, Australian Psychologist 49, 163- 170.

Items of the Strengths and Difficulties Questionnaire (SDQ)

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

The source content provided the domains measured by the 25 items, but not the specific text of the questions themselves. The SDQ is structured into five subscales, each containing five items:

• Emotional Symptoms Scale (5 items)
• Conduct Problems Scale (5 items)
• Hyperactivity/Inattention Scale (5 items)
• Peer Relationship Problems Scale (5 items)
• Prosocial Behavior Scale (5 items)

The Total Difficulties Score is the sum of the first four scales (20 items).