Controllability of Suicidal Thoughts Scale (CoST)
Measures an individual's perceived control over their suicidal thoughts.
Scale Development & Technical Details
Scale Overview
The Controllability of Suicidal Thoughts Scale (CoST) was developed by Brianna Meddaoui, Bianca C. Iddiols, & Erin A. Kaufman (2023). It is designed to measure Perceived control over suicidal thoughts. The scale is intended for use with Adults (18 years & older).
Scale Structure
This instrument consists of 10 items organized into 2 factors/subscales: General Control, Changing Thought Content.
| Factor / Subscale | Items | N |
|---|---|---|
| General Control | 1,2,3,4,5,6,7 | 7 |
| Changing Thought Content | 8,9,10 | 3 |
Response Format
Respondents rate each item using a 7-point Likert scale (1 = Strongly Disagree to 7 = Strongly Agree).
The scale includes 6 reverse-scored items to reduce acquiescence bias.
Scoring
Items are summed to produce a total score.
Total scores range from 10 to 70. Interpretation guidelines:
- Low Perceived Control: 10 – 30
- Moderate Perceived Control: 31 – 50
- High Perceived Control: 51 – 70
Psychometric Properties
Internal Consistency: The scale has demonstrated good to excellent internal consistency with reported Cronbach’s alpha values of omega = .92.
Administration
The scale is self-administered and typically takes approximately 3 minutes to complete. It can be administered individually or in group settings. No special training is required for administration.