Volume 23, Number 11—November 2017
Research
Weather-Dependent Risk for Legionnaires’ Disease, United States
Table 2
Demographic and severity characteristics among dropped and retained records in a study of weather-dependent risk for Legionnaires’ disease, United States, 1998–2011*
| Characteristics | Cases |
Controls |
|||||
|---|---|---|---|---|---|---|---|
| Dropped, n = 2,153 | Retained, n = 3,005 | p value | Dropped, n = 228,674 | Retained, n = 189,412 | p value | ||
| Mean age, y (± SD) | 60.6 (15.7) | 61.8 (15.6) | 0.0078 | 68.2 (17.1) | 68.8 (17.2) | <0.0001 | |
| Female, % | 39.6 | 39.1 | 0.7138 | 48.1 | 48.2 | 0.4170 | |
| Privately insured, % | 39.0 | 38.8 | 0.8814 | 19.6 | 17.0 | <0.0001 | |
| Not insured, % | 11.2 | 7.7 | <0.0001 | 6.2 | 4.5 | <0.0001 | |
| Mean no. diagnoses (± SD) | 9.6 (4.1) | 9.6 (4.3) | 0.9213 | 8.2 (3.9) | 9.4 (4.3) | <0.0001 | |
| Mean no. procedures (± SD)† | 1.9 (2.5) | 1.9 (2.8) | 0.6027 | 1.0 (1.8) | 1.4 (2.2) | <0.0001 | |
*Many of the significant differences in the controls resulted from the large sample and might not be clinically significant. The analysis comprised data from 26 states: Arizona, Arkansas, California, Colorado, Connecticut, Illinois, Iowa, Kentucky, Maryland, Massachusetts, Mississippi, Missouri, Montana, Nevada, New Hampshire, New Jersey, New York, North Carolina, Oregon, Pennsylvania, Rhode Island, Utah, Vermont, Virginia, Washington, Wisconsin.
†Any type of procedure recorded in the Agency for Healthcare Research and Quality’s Healthcare Cost and Utilization Project; this was a measure of severity, and this variable was not included in the model.