Adult ADHD Clinical Outcome Scale – ACOS
A concise self-report tool developed to measure clinical outcomes and symptom severity in adults with ADHD.
Scale Development & Technical Details
Scale Overview
The Adult ADHD Clinical Outcome Scale – ACOS was developed by Dimitrios Adamis, Jasmin Singh, Iulian Coada, Margo Wrigley, Blánaid Gavin, Fiona McNicholas (2024). It is designed to measure ADHD Clinical Outcomes. The scale is intended for use with Adults (18+).
Scale Structure
This instrument consists of 15 items organized into 4 factors/subscales: Attention/Function, Dysregulation, Comorbidities, Risk-Taking Behaviours.
| Factor / Subscale | Items | N |
|---|---|---|
| Attention/Function | 2,6,10,14,15 | 5 |
| Dysregulation | 1,3,5,7 | 4 |
| Comorbidities | 8,11,12,13 | 4 |
| Risk-Taking Behaviours | 4,9 | 2 |
Response Format
Respondents rate each item using a custom response format.
Response anchors: 0 = Not at all, 1 = A little, 2 = Somewhat, 3 = A lot, 4 = Very much, 5 = Extremely.
Scoring
Items are scored by subscale, with each subscale sum representing a distinct dimension.
Total scores range from 0 to 75. Interpretation guidelines:
- Minimal clinical impairment: 0 – 15
- Mild clinical impairment: 16 – 30
- Moderate clinical impairment: 31 – 45
- Severe clinical impairment: 46 – 75
Psychometric Properties
Internal Consistency: The scale has demonstrated good to excellent internal consistency with reported Cronbach’s alpha values of Cronbach's alpha = 0.928.
Administration
The scale is self-administered and typically takes approximately 5 minutes to complete. It can be administered individually or in group settings. No special training is required for administration.