Controllability of Suicidal Thoughts Scale (CoST)

Abstract

The Controllability of Suicidal Thoughts Scale (CoST), developed by Meddaoui, Iddiols, and Kaufman in 2023, is designed to evaluate an individual’s perception of control over their suicidal thoughts. The scale’s content was crafted to ensure face validity, drawing upon relevant empirical and theoretical literature concerning suicidality, coping mechanisms, and the concept of control, with notable reference to Batterham et al. (2015). The CoST is a 10-item questionnaire that was validated using adult residents from Canadian and American samples who were recruited online. The evaluation included factor analysis, reliability assessments, and validity testing of the items. The primary objective of this questionnaire is to quantify a person’s perceived ability to manage their suicidal thoughts, which is crucial for determining risk levels.

Keywords

Suicidal Thoughts; General Control; Changing Thought Content; Incremental Validity

Authors

Meddaoui, Brianna; Iddiols, Bianca C.; Kaufman, Erin A.

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Purpose

The purpose of this questionnaire is to measure a person’s sense of perceived control over their suicidal thoughts, which may be important for understanding risk level.

Validity

Convergent and Discriminant Validity: Correlation coefficients between CoST scores and constructs of coping and control were found to be weaker when compared to their correlation with suicide-specific constructs.

Concurrent and Predictive Validity: Higher total scores on the CoST predicted a decrease in suicidal ideation (SI) severity both at baseline (β = −0.52, SE = 0.14, p < .001) and one month later (β = −0.44, SE = 0.18, p < .001). Similar prospective effects were observed for the Control and Change subscales, which independently predicted SI severity (i.e., β = −0.38; −0.44, SE = 0.25; 0.51, p < .00).

Incremental Validity: CoST total scores significantly predicted a substantial amount of variability in SI severity, even after accounting for hopelessness ( f2 = .12), self-efficacy to avoid suicidal action ( f2 = .05), and suicide-related coping ( f2 = .07).

Reliability

Internal Consistency: The CoST demonstrated high internal consistency, with a ω (omega) coefficient of .92.

Test-Retest Reliability: The test–retest reliability was strong across the board, with the full scale showing r = 0.86, the control factor showing r = 0.83, and the change factor showing r = 0.83.

Factor Analysis

Exploratory Factor Analysis: Initial analysis using a scree plot and parallel analysis indicated five factors with eigenvalues greater than 1. However, solutions with more than two factors proved to be unstable, accounting for only 3%–4% of the variance and containing items with weak loadings or cross-loading onto multiple factors, as noted by Costello & Osborne (2005). The two-factor solution was deemed the most appropriate and parsimonious fit for the data, explaining approximately 48% of the total variance.

Confirmatory Factor Analysis: This model showed a good fit to the data based on certain indices (CFI = 0.94, TLI = 0.92, SRMR = 0.05) and an adequate fit according to others (RMSEA = 0.07, 90% CI [0.05, 0.09]).

Instrument: Controllability of Suicidal Thoughts Scale (CoST)

Test Type: Original Inventory/Questionnaire

Format: Items are scored on a 7-point Likert scale, ranging from 1 (strongly disagree) to 7 (strongly agree). Sixteen items are reverse-scored to mitigate response bias. Scores are summed to generate a total score, with higher scores indicating a greater perceived sense of control.

Language Available: English

Population Group: Human; Male; Female

Age Group: Adulthood (18 years & older)

Population Details: Respondents are adult residents from Canada and the United States.

Test Methodology: Test Validity (Concurrent Validity, Convergent Validity, Discriminant Validity, Predictive Validity); Test Reliability (Internal Consistency, Test-Retest Reliability); Factor Analysis (Confirmatory Factor Analysis, Exploratory Factor Analysis).

Keywords

Suicidal Ideation; Perceived Control; Mental Health Attitude Measures; Mental Health (Attitudes Toward)

Authors

Author ORCID Identifier:

• Meddaoui, Brianna: http://orcid.org/0000-0002-8813-5844

• Kaufman, Erin A.: http://orcid.org/0000-0002-7636-6602

Affiliation:

• Meddaoui, Brianna: University of Western Ontario, Department of Psychology

• Iddiols, Bianca C.: University of Western Ontario, Department of Psychology

• Kaufman, Erin A.: University of Western Ontario, Department of Psychology

Email addresses:

• Meddaoui, Brianna: [email protected]

Correspondence Address:

Meddaoui, Brianna: University of Western Ontario, Department of Psychology, 361 Windermere Road, London, Ontario, Canada, N6A 3K7, [email protected]

Permissions & Fee and Test Year

Permissions: May be used for Research/Teaching.
Fee: No
Commercial: No
Test Year: 2023

References

Meddaoui, B., Iddiols, B. C., & Kaufman, E. A. (2023). The Controllability of Suicidal Thoughts (CoST) Scale: Development, factor structure, and initial validation. Psychological Assessment, 35(10), 880–887. https://doi.org/10.1037/pas0001271

Items of the Controllability of Suicidal Thoughts Scale (CoST)

Items

The following statements pertain to thoughts about suicide. This may include thoughts such as “I don’t want to be alive anymore,” “I wish I were dead,” or “I want to kill myself.” When we say thoughts, we mean ideas you have, words you say to yourself in your head, and/or images you think about.
Typically, when I have thoughts about suicide, I…

Scoring

Scales can be summed to create a total score, ranging from 10 – 70. The six items to be reverse coded are indicated in grey. Higher total and subscale scores reflect better perceived control over one’s suicidal thoughts.

Subscales

General Control

1. When I’m upset, I believe that I will end up feeling very depressed.

2. When I’m upset, I believe there is nothing I can do to make myself feel better.

3. When I’m upset, it takes me a long time to feel better.

4. Cannot control these thoughts

5. Become stuck in these thoughts

6. Am able to easily shift my focus away from these thoughts

7. Feel like I’m in control of these thoughts

Changing Thought Content

1. When I’m upset, I become embarrassed for feeling that way.

2. When I’m upset, I feel guilty for feeling that way.

3. When I’m upset, I become irritated at myself for feeling that way.