Understanding SRS-2 Scoring and Interpretation for ASD

Introduction

The Social Responsiveness Scale, Second Edition (SRS-2) is a 65-item rating scale. It is used to measure the severity of autism spectrum disorder (ASD) symptoms. These symptoms are observed as they occur in natural social settings. This guide will help you understand and interpret SRS-2 scores.

SRS-2 Forms

The SRS-2 has four forms:

1. Preschool (ages 2.5 to 4.5 years)
2. School-Age (ages 4 to 18 years)
3. Adult (ages 19 and up)
4. Adult Self-Report (ages 19 and up)

Scoring

The SRS-2 yields several scores:

1. Total Score
2. DSM-5 Compatible Scales:
   • Social Communication and Interaction (SCI)
   • Restricted Interests and Repetitive Behavior (RRB)
3. Treatment Subscales:
   • Social Awareness
   • Social Cognition
   • Social Communication
   • Social Motivation
   • Restricted Interests and Repetitive Behavior

Interpreting T-Scores

SRS-2 raw scores are converted to T-scores with a mean of 50 and a standard deviation of 10. T-scores allow for comparison across different age groups and genders.

T-Score Ranges and Interpretations:

Interpreting Total Score

The Total Score is the most reliable and provides an overall measure of ASD symptoms. It’s derived from the sum of responses to all 65 items on the SRS-2. This score is particularly useful for screening purposes and for tracking changes over time or in response to interventions.

T-Score Ranges and Interpretations:

1. T-score ≤ 59: Within normal limits
   • Interpretation: Social responsiveness is within normal limits.
   • Clinical Implications:
     • Suggests the individual is not experiencing significant difficulties in social interactions.
     • ASD is unlikely but not ruled out if other evidence suggests otherwise.
   • Example: A child who interacts well with peers, shows appropriate emotional responses, and doesn’t display unusual repetitive behaviors.
2. T-score 60-65: Mild range
   • Interpretation: Indicates mild deficits in reciprocal social behavior that are clinically significant.
   • Clinical Implications:
     • May be associated with milder forms of ASD such as PDD-NOS or Asperger’s Syndrome (using DSM-IV terminology).
     • Could indicate subclinical autistic traits or the broader autism phenotype.
     • Warrants closer observation and possibly further assessment.
   • Example: A child with difficulties in social situations may struggle with maintaining conversations. They might have trouble understanding social cues, yet they can generally function in everyday situations.
3. T-score 66-75: Moderate range
   • Interpretation: Indicates clinically significant deficits in reciprocal social behavior that substantially interfere with everyday social interactions.
   • Clinical Implications:
     • Strongly associated with a clinical diagnosis of ASD.
     • Indicates a need for further comprehensive assessment if ASD has not been diagnosed.
     • Suggests a need for substantial support and intervention in social skills.
   • Example: An individual struggles significantly in social situations. They have difficulty forming and maintaining relationships. They may display noticeable repetitive behaviors or restricted interests.
4. T-score ≥ 76: Severe range
   • Interpretation: Suggests severe deficits in reciprocal social behavior that lead to severe and enduring interference with everyday social interactions.
   • Clinical Implications:
     • Very strongly associated with a clinical diagnosis of ASD.
     • Indicates a need for comprehensive intervention and support across multiple domains.
     • May suggest the presence of more severe forms of ASD.
   • Example: An individual faces major challenges in social communication and interaction. This may include minimal verbal communication and very limited social reciprocity. Additionally, they may exhibit pronounced repetitive behaviors or have restricted interests.

Additional Considerations for Total Score Interpretation:

1. Sensitivity vs. Specificity: The SRS-2 is designed to be highly sensitive. Therefore, it may sometimes identify individuals who do not have ASD (false positives). This is preferable to missing individuals who do have ASD.
2. Age and Gender: Interpretation should always consider age- and gender-specific norms. What’s considered “normal” can vary based on developmental stage and gender.
3. Cultural Factors: Social norms and expectations can vary across cultures. Interpret scores with cultural context in mind.
4. Comorbidities: Other conditions like ADHD, anxiety, or language disorders can elevate SRS-2 scores. Consider the possibility of comorbid conditions when interpreting high scores.
5. Environmental Factors: Recent significant life events or changes in the individual’s environment can impact social behavior and potentially influence scores.
6. Longitudinal Perspective: Consider how an individual’s scores change over time. This can be particularly useful for monitoring response to interventions.
7. Informant Perspective: Remember that scores can vary based on who completes the assessment (e.g., parent vs. teacher). Multiple informants can provide a more comprehensive picture.
8. Subscale Profile: The Total Score provides an overall measure. By examining the profile of subscale scores, one can gain insights into specific areas of strength and difficulty.

Remember, while the Total Score is a powerful indicator, it should always be interpreted as part of a comprehensive assessment. This includes clinical observation, developmental history, and other standardized measures when appropriate.

Interpreting DSM-5 Compatible Scales

Social Communication and Interaction (SCI)

This scale aligns with DSM-5 criteria for ASD in the domain of social communication and interaction.

• High scores indicate difficulties in:
  • Social awareness
  • Social information processing
  • Capacity for reciprocal social communication
  • Social anxiety/avoidance
  • Characteristic autistic preoccupations and traits

Restricted Interests and Repetitive Behavior (RRB)

This scale corresponds to the DSM-5 domain of restricted interests and repetitive behavior.

• High scores indicate:
  • Stereotypical behaviors or highly restricted interests characteristic of autism
  • Rigidity and inflexibility
  • Behavioral and cognitive rigidity

Interpreting Treatment Subscales

1. Social Awareness: Ability to pick up on social cues
2. Social Cognition: Ability to interpret social cues once picked up on
3. Social Communication: Expressive social communication
4. Social Motivation: Extent of motivation to engage in social-interpersonal behavior
5. Restricted Interests and Repetitive Behavior: Stereotypical behaviors or highly restricted interests characteristic of autism

These subscales can help in treatment planning by identifying specific areas of strength and weakness.

Clinical Applications

In clinical settings, the SRS-2 is valuable for:

• Screening for ASD
• Supporting diagnostic decisions
• Developing targeted interventions
• Monitoring treatment progress
• Research on social impairment and ASD

Remember that while the SRS-2 is a powerful tool, it should not be used in isolation to diagnose ASD. A comprehensive evaluation by qualified professionals is necessary for a formal diagnosis.

Clinicians and researchers can use the SRS-2 effectively by understanding these interpretation guidelines. They can assess social responsiveness and guide interventions for individuals with potential autism spectrum disorders.

Considerations in Interpretation

1. Multiple Informants: When possible, gather data from multiple informants (e.g., parents, teachers) for a more comprehensive picture.
2. Context: Consider the context of the individual’s life, including cultural factors, when interpreting scores.
3. Comorbidities: Be aware that other conditions (e.g., ADHD, anxiety) can influence SRS-2 scores.
4. Age and Gender: Use the appropriate norms for the individual’s age and gender when interpreting scores.
5. Comprehensive Assessment: The SRS-2 should be used as part of a comprehensive assessment, not as a standalone diagnostic tool.

Conclusion

The SRS-2 is a valuable tool for assessing ASD symptoms. However, interpretation should always be done by qualified professionals. They should use it in conjunction with other assessment methods and clinical judgment.