Non-Suicidal Self-Injury Assessment Tool (NSSI-AT): A Full Guide for Researchers and Clinicians
Published
The NSSI-AT is a modular web-based measure of nonsuicidal self-injury forms, functions and impacts. Learn its 12 modules, scoring and evidence base.
Introduction
The Non-Suicidal Self-Injury Assessment Tool (NSSI-AT) is a web-based measure of the primary and secondary characteristics of nonsuicidal self-injury (NSSI) and its relationship with suicidal thoughts and behaviors. Janis Whitlock, Deinera Exner-Cortens and Amanda Purington published it in 2014 in Psychological Assessment. It is designed for research in community populations of young adults and adults.
The NSSI-AT has received about 230 citations. This guide explains its 12 modules, how each module is scored, and what the original validation study found.
Key Features of the NSSI-AT
Purpose and Use
The NSSI-AT assesses two levels of NSSI characteristics:
Primary characteristics: form, frequency and function.Secondary characteristics: habituation, practice contexts, perceived life interference, treatment experiences and impacts.It also captures the relationship between NSSI and suicidal thoughts and behaviors, for research in community populations.
Target Population
The NSSI-AT is designed for community populations of young adults and adults. The original validation took place in a university population aged 18–25 (mean age 20.31, SD 1.80).
Structure
The NSSI-AT has 12 modules with a variable number of items, so no fixed total item count is reported. Module A screens for 16 NSSI behaviors plus an "other" option. Only respondents who screen positive see the later modules, which cover:
Functions (18 items)Recency and lifetime frequency, and age of onsetWound locations (17 locations) and severity (8 items)Practice patterns (7 items)Habituation (4 items) and perceived life interferenceDisclosure and treatment experiencesPersonal reflections on impact (7 items)Scoring Method
Each module has its own response format and scores:
Module
Response format
Scores
Behavior screen (Module A)
Yes/no
Any endorsement leads to later modules
Functions (18 items)
Yes/no
Five subscales: Affective Imbalance–Low Pressure (0–4), Affective Imbalance–High Pressure (0–3), Social Communication and Expression (0–3), Self-Retribution and Deterrence (0–4), Sensation Seeking (0–4)
Frequency and recency
7-point interval scales
From "only once" to "more than 50 times" for frequency
Habituation (4 items)
5-point Likert scale
Total 4–20; higher means greater habituation
Wound locations
Yes/no
Count of locations
Severity and practice patterns
Yes/no
Endorsed items
Personal reflections
Yes/no
Ambivalence and Growth subscales
Because the tool is modular, a total score for the whole instrument does not apply. No cut-off scores are reported.
Administration Format
The NSSI-AT is completed online by the respondent. Skip patterns mean that each person answers only the modules relevant to them.
Applications of the NSSI-AT
The NSSI-AT is a research instrument:
Community research: describing NSSI characteristics in young adult and adult populations.Functions and impacts: studying why people self-injure and how it affects their lives.Links with suicidality: examining the relationship between NSSI and suicidal thoughts and behaviors.Reliability and Validity
In the original validation study, the NSSI-AT showed acceptable test–retest reliability and promising validity evidence for its behavior and frequency modules.
Validation studies:
Assessment of nonsuicidal self-injury: development and initial validation of the NSSI-AT (2014): study linkLimitations and Considerations
Keep these points in mind:
Low internal consistency: some subscales showed low internal consistency.Further validation: validation in diverse populations and refinement of certain modules are recommended.University sample: interpret scores cautiously outside the university population used for validation.Other Versions And Related Questionnaires
These measures of self-injury are related:
Deliberate Self-Harm Inventory (DSHI)Functional Assessment of Self-Mutilation (FASM)Inventory of Statements About Self-Injury (ISAS)Self-Harm Behavior Questionnaire (SHBQ)Self-Injurious Thoughts and Behaviors Interview (SITBI)Suicide Attempt Self-Injury Interview (SASSI)Additional Resources
The original article on APA PsycNet: linkThe article as a PDF from Cornell University: linkFor inquiries, see Janis Whitlock's Cornell University profile.Browse more psychiatry questionnaires in the ResRef database.Frequently Asked Questions (FAQ)
What does the NSSI-AT measure?The NSSI-AT measures the forms, frequency and functions of nonsuicidal self-injury, plus secondary features such as habituation, life interference, treatment experiences and links with suicidal thoughts and behaviors.
How many items does the NSSI-AT have?No fixed total exists. The tool has 12 modules, and skip patterns show later modules only to people who screen positive, so the number of items varies by respondent.
Does the NSSI-AT have a total score?No. Because it is modular, each module has its own scores, such as five function subscales and a 4–20 habituation total, and no cut-off scores are reported.
Who is the NSSI-AT designed for?It is designed for research in community populations of young adults and adults. The original validation used university students aged 18 to 25.
A Word from ResRef About the NSSI-AT
The NSSI-AT is a comprehensive, web-based tool for assessing a broad range of NSSI characteristics in community samples of young adults and college students. It demonstrated acceptable test-retest reliability and promising validity evidence for its behavior and frequency modules in the original validation study. Clinicians and researchers should note that internal consistency for some subscales was low, and further validation in diverse populations, as well as refinement of certain modules, is recommended. Interpretation of scores outside the university population should be cautious.
References
Whitlock, J., Exner-Cortens, D., & Purington, A. (2014). Assessment of nonsuicidal self-injury: development and initial validation of the Non-Suicidal Self-Injury-Assessment Tool (NSSI-AT). Psychological Assessment, 26(3), 935–46. https://doi.org/10.1037/a0036611