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Change in variance in practices' quality scores 1998-2003
|
Pitman's t test of correlated variances
|
|||||
|---|---|---|---|---|---|
| Condition | SD; range in 1998 | SD; range in 2003 | t | df | P value |
| Coronary heart disease (41 practices) | 9.68; 37.36-75.67 | 11.10; 44.8-94.8 | 0.84 | 39 | 0.41 |
| Asthma (42 practices) | 16.47; 20.6-85.5 | 15.93; 35.8-96.6 | −0.23 | 40 | 0.82 |
| Diabetes (42 practices) | 13.74; 35.0-88.9 | 11.44; 43.2-93.4 | −1.34 | 40 | 0.19 |
