CDC Healthy Days Symptoms Module
Measures the number of healthy and unhealthy days related to physical and mental symptoms over the past 30 days.
Scale Development & Technical Details
Scale Overview
The CDC Healthy Days Symptoms Module was developed by Centers for Disease Control and Prevention (CDC) (2000). It is designed to measure Health-Related Quality of Life. The scale is intended for use with Adults.
Scale Structure
This instrument consists of 5 items organized into 5 factors/subscales: Pain-Free Days, Depression-Free Days, Anxiety-Free Days, Sleep-Sufficient Days, Vitality Days.
| Factor / Subscale | Items | N |
|---|---|---|
| Pain-Free Days | 1 | 1 |
| Depression-Free Days | 2 | 1 |
| Anxiety-Free Days | 3 | 1 |
| Sleep-Sufficient Days | 4 | 1 |
| Vitality Days | 5 | 1 |
Response Format
Respondents rate each item using a custom response format.
Response anchors: 0 = 0 days, 30 = 30 days.
The scale includes 4 reverse-scored items to reduce acquiescence bias.
Scoring
Items are scored by subscale, with each subscale sum representing a distinct dimension.
Total scores range from 0 to 30. Interpretation guidelines:
- Number of healthy days (calculated per item): 0 – 30
Psychometric Properties
Internal Consistency: The scale has demonstrated good to excellent internal consistency with reported Cronbach’s alpha values of Not specified.
Administration
The scale is self-administered and typically takes approximately 2 minutes to complete. It can be administered individually or in group settings. No special training is required for administration.