Table 3.
Convergent validity for stroke specific quality of life (SS-QOL); Item scaling tests
| Scale | Number of items per scale | Convergent validity (range of correlation) | Scaling success * | Scaling success ** | Internal consistency (Cronbach’s alpha) | Divergent validity (range of correlation) |
|---|---|---|---|---|---|---|
| Energy | 3 | 0.75-0.89 | 3/3 | 100 | 0.80 | 0.08-0.49 |
| Family role | 3 | 0.68-0.88 | 3/3 | 100 | 0.74 | 0.03-0.78 |
| Language | 5 | 0.75-0.83 | 5/5 | 100 | 0.94 | 0.13-0.47 |
| Self-care | 5 | 0.77-0.91 | 5/5 | 100 | 0.92 | 0.12-0.82 |
| Social role | 5 | 0.76-0.88 | 5/5 | 100 | 0.88 | 0.14-0.72 |
| Thinking | 3 | 0.82-0.87 | 3/3 | 100 | 0.81 | -0.08-0.45 |
| Mood | 5 | 0.53-0.85 | 5/5 | 100 | 0.80 | 0.14-0.53 |
| Personality | 3 | 0.85-0.90 | 3/3 | 100 | 0.86 | 0.14-0.58 |
| Upper extremity function | 5 | 0.79-0.84 | 5/5 | 100 | 0.92 | 0.11-0.79 |
| Vision | 3 | 0.82-0.86 | 3/3 | 100 | 0.85 | 0.06-0.37 |
| Work (Productivity) | 3 | 0.81-0.92 | 3/3 | 100 | 0.86 | 0.11-0.78 |
| Mobility | 6 | 0.79-0.93 | 6/6 | 100 | 0.94 | 0.05-0.78 |
Spearman’s correlation coefficient was used for assessing convergent and divergent validities of each scale and corresponding items
*
Number of correlations between items and hypothesized scale corrected for overlap > 0.4/total number of convergent validity tests;
**
Scaling success rate of previous column as percentage