Clinical change thresholds

A raw score change from week to week tells you direction. A clinically meaningful change tells you whether the change is large enough to act on. What follows is a quick reference for the change thresholds on the most-used measures in the Rivet library. Rivet shows the raw score and the severity band; the interpretation of whether a change is clinically meaningful is yours.

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What “clinically meaningful change” means

A change in score is clinically meaningful when it’s larger than the measurement noise of the instrument — i.e. larger than what you’d expect from session-to-session variation alone. Different research traditions operationalize this differently:

• Reliable Change Index (RCI) — the change a client would need to show for you to be statistically confident the change isn’t just measurement noise (Jacobson & Truax 1991).
• Minimal Clinically Important Difference (MCID) — the smallest change a client or clinician would notice as actually meaningful.
• Severity band crossing — a drop from “moderately severe” to “mild” is meaningful regardless of the absolute change.

For most published scales there’s a single working number — that’s the number below.

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Per-measure thresholds

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PHQ-9 (depression)

• 5-point change is the working threshold for clinically significant improvement (Kroenke 2010 follow-up).
• Severity band crossings matter independently: moving from “moderately severe” (15–19) to “moderate” (10–14) is meaningful even if the absolute drop is smaller.
• Score ≥ 10 is the screening threshold for major depression.

Citation: Kroenke, K., Spitzer, R. L., & Williams, J. B. W. (2001). J Gen Intern Med, 16(9): 606–613.

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GAD-7 (generalized anxiety)

• 4-point change is the working threshold for meaningful improvement.
• Score ≥ 10 is the threshold for probable generalized anxiety disorder and the trigger for further assessment.

Citation: Spitzer, R. L., Kroenke, K., Williams, J. B. W., & Löwe, B. (2006). Archives of Internal Medicine, 166(10): 1092–1097.

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PCL-5 (PTSD symptoms)

• 5- to 10-point change is the working threshold for reliable change (Bovin 2016). The narrower number reflects research-grade reliable change; the wider one is the clinically meaningful threshold most commonly cited.
• Score ≥ 31–33 is the cutoff for probable PTSD.
• Cluster-specific change matters: an overall drop driven entirely by Cluster D (cognition / mood) without movement in Cluster B (intrusion) suggests something different than a uniform reduction.

Citation: Bovin, M. J., et al. (2016). Psychological Assessment, 28(11): 1379–1391.

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K10 (psychological distress)

• 5-point change is the practical threshold; K10’s bands are 5-point wide (low / mild / moderate / severe) so a band crossing and an MCID roughly coincide.

Citation: Kessler, R. C., et al. (2002). Psychological Medicine, 32(6): 959–976.

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DASS-21 (depression, anxiety, stress)

Each subscale has its own bands and thresholds (the 21-item version sums each subscale × 2 to align with the 42-item norms — Rivet handles the multiplier automatically). A useful working threshold:

• Depression subscale: ~9-point change at the multiplied score
• Anxiety subscale: ~7-point change
• Stress subscale: ~9-point change

The above are rough working numbers commonly cited in DASS application literature; the original Lovibond & Lovibond (1995) manual focuses on severity bands rather than a single MCID.

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PSS-10 (perceived stress)

• 3- to 5-point change is a commonly-cited working threshold.
• No formal clinical cutoff — descriptive measure with bands (low / moderate / high stress).

Citation: Cohen, S., Kamarck, T., & Mermelstein, R. (1983). Journal of Health and Social Behavior, 24(4): 385–396.

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ISI (insomnia)

• 6-point change is the published meaningful improvement threshold for CBT-I outcomes.
• Score ≥ 15 is the cutoff for clinical insomnia.

Citation: Bastien, C. H., Vallières, A., & Morin, C. M. (2001). Sleep Medicine, 2(4): 297–307.

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AUDIT (alcohol use)

• Score ≥ 8 is the WHO cutoff for hazardous drinking (≥ 7 for women in some adaptations).
• Score ≥ 16 indicates harmful drinking.
• Score ≥ 20 suggests possible alcohol dependence and warrants further evaluation.
• Change-from-baseline matters more than a single MCID for AUDIT; the WHO scoring rubric focuses on bands.

Citation: Babor, T. F., Higgins-Biddle, J. C., Saunders, J. B., & Monteiro, M. G. (2001). AUDIT: The Alcohol Use Disorders Identification Test (2nd ed.). WHO.

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WHO-5 (well-being)

• 10-point change on the 0–100 percentage scale is the working threshold (the 0–25 raw score is multiplied by 4 to produce the percentage; Rivet applies the multiplier automatically).
• ≤ 28% indicates a need for further depression screening.

Citation: Topp, C. W., Østergaard, S. D., Søndergaard, S., & Bech, P. (2015). Psychotherapy and Psychosomatics, 84(3): 167–176.

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What Rivet shows; what’s yours

Rivet shows you:

• The raw subscale score
• The multiplied score where the algorithm requires it (DASS-21 × 2, WHO-5 × 4)
• The matching severity band
• Whether any cutoff fired (e.g. “probable PTSD”, “clinical insomnia”)

Rivet does not:

• Compute a Reliable Change Index from prior sessions (no longitudinal data; that’s your chart’s job)
• Tell you whether a specific change is “clinically significant” — that’s a judgment that takes the trajectory, the client’s life context, and treatment phase into account
• Diagnose anything — cutoffs surface a screening signal, not a diagnosis

The numeric thresholds above are practitioner shorthand. The interpretation of what to do about a score change is the practice of psychotherapy, which remains yours.

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