SPS: Suicide Probability Scale
Suicide Probability Scale · Also known as: SPS, Suicide Probability Scale, Cull-Gill SPS
The Suicide Probability Scale (SPS) is a 36-item self-report instrument developed by John Cull and William Gill (1990) to assess suicide risk, hopelessness, suicide ideation, negative self-evaluation, and hostility in adolescents and adults. It provides a multidimensional profile of suicide-related cognitions and emotions and is used in clinical, psychiatric, school, and forensic settings to screen for suicide risk and guide treatment planning.
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When to use it
SPS is indicated for suicide risk screening and assessment in school psychology, clinical psychology, psychiatric, and forensic settings. It is used at initial evaluation, serially during treatment to monitor risk trajectory, and in crisis triage. SPS is particularly useful in non-emergency settings (school counseling, primary care, outpatient mental health) where brief screening is appropriate. It is applicable to adolescents (age 14+) and adults. SPS is not recommended as a sole instrument for acute emergency or crisis situations without comprehensive clinical assessment and direct safety evaluation.
Strengths & limitations
- Multidimensional assessment captures hopelessness, ideation, self-evaluation, and hostility—multiple cognitive-emotional domains relevant to suicide risk—rather than single dimension.
- Yields both dimensional subscale profiles and categorical risk classifications; subscale elevation guides specific treatment targets.
- Brief administration (10–15 minutes) and straightforward self-report format make it suitable for routine screening in outpatient and school settings.
- Age- and gender-normed scoring provides precise interpretation and comparison to same-age peers.
- Validated in adolescents and adults across clinical, school, and forensic populations; research demonstrates adequate reliability and validity.
- Clinical utility in treatment planning: subscale profiles identify specific cognitive-emotional intervention targets.
- Incorporates hostility dimension, recognizing anger and aggressive impulses as suicide risk factors (particularly in forensic populations).
- Self-report methodology vulnerable to response bias, particularly in forensic or legal contexts where minimal distress may support favorable outcomes.
- Does not directly assess suicidal intent, specific plan, access to means, or capability—all critical suicide risk factors; should be supplemented with behavioral and situational assessment.
- Categorical classifications (No/Mild/Moderate/High Risk) may give false sense of precision; considerable heterogeneity exists within each category.
- Less extensively validated than some other suicide risk instruments (e.g., Beck Hopelessness Scale, C-SSRS); fewer published prospective prediction studies.
- Requires adequate reading comprehension and insight; validity compromised in individuals with severe cognitive impairment, active psychosis, or acute intoxication.
- Does not systematically assess protective factors; lower subscale scores do not account for protective factors that may decrease suicide risk.
Frequently asked
What is the difference between 'Moderate Risk' and 'High Risk' on the SPS?
Moderate Risk indicates substantially elevated suicide-related cognitions and emotions requiring active treatment (psychotherapy, pharmacotherapy) but typically manageable in outpatient or inpatient settings with standard psychiatric care. High Risk indicates imminent, substantial suicide threat typically requiring hospitalization, intensive monitoring, and emergency safety interventions. The distinction guides setting level and treatment intensity, though both levels require professional mental health response.
If a student scores 'No Risk' on the SPS, can suicide be ruled out?
No. A low SPS score indicates minimal elevation on hopelessness, ideation, negative self-evaluation, and hostility at the time of assessment, but does not rule out suicide risk. Suicide can occur in individuals without elevated psychological vulnerability (e.g., impulsive response to acute stressor, psychotic command hallucination). SPS is screening tool, not definitive risk assessment; clinical judgment and behavioral observation are essential.
How often should SPS be readministered?
In clinical treatment, SPS can be administered at baseline and periodic intervals (e.g., monthly) to monitor treatment response. In school settings, annual screening is common, with more frequent reassessment following concerning disclosures or behavioral observations. In forensic or acute psychiatric settings, baseline and post-treatment/stabilization reassessment is standard. Frequent reassessment may use brief rating scales rather than full SPS for tracking.
Can elevated Hostility on SPS predict violence?
Elevated Hostility on SPS indicates irritability, anger, and aggressive impulses. While hostility is a risk factor for aggression and violence, SPS is primarily a suicide risk instrument. Violence risk assessment requires dedicated instruments (HCR-20, VRAG) and comprehensive evaluation of aggressive behavior history, capacity for harm, and context. SPS Hostility subscale contributes to but does not determine violence risk.
Is there a 'cutoff score' for SPS that predicts suicide attempt?
The SPS provides categorical classifications (No/Mild/Moderate/High Risk) rather than a single definitive cutoff. Moderate and High Risk classifications indicate elevated probability of suicide-related distress and warrant professional evaluation, but suicide attempt is not certain. Individual risk depends on additional factors (acute stressors, access to means, specific plan, protective factors) not fully captured by SPS alone.
Sources
How to cite this page
ScholarGate. (2026, June 3). Suicide Probability Scale. ScholarGate. https://scholargate.app/en/forensic-psychology/suicide-probability-scale
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