Table 3.
Variables | Olanzapine Hazard ratio |
P- Value |
Quetiapine Hazard ratio |
P- Value |
Ziprasidone Hazard ratio |
P- Value |
Aripiprazole Hazard ratio |
P- Value |
---|---|---|---|---|---|---|---|---|
Sex | ||||||||
Female | .84 | <.001 | .86 | <.001 | .87 | <.001 | .91 | .001 |
Male | Reference | Reference | Reference | Reference | ||||
Age | ||||||||
<30 | 1.07 | .545 | 1.48 | <.001 | 1.52 | <.001 | 1.43 | <.001 |
30–39 | 1.33 | <.001 | 1.45 | <.001 | 1.47 | <.001 | 1.45 | <.001 |
40–49 | 1.33 | <.001 | 1.38 | <.001 | 1.34 | <.001 | 1.34 | <.001 |
50+ | Reference | Reference | Reference | Reference | ||||
Specialty | ||||||||
General Practice | .28 | <.001 | .35 | <.001 | .18 | <.001 | .22 | <.001 |
Pediatrics | .24 | <.001 | .25 | <.001 | .21 | <.001 | .38 | <.001 |
Neurology | .33 | <.001 | .54 | <.001 | .16 | <.001 | .16 | <.001 |
Psychiatrist | Reference | Reference | Reference | Reference | ||||
Practice Setting | ||||||||
Solo | .89 | <.001 | .86 | <.001 | .95 | .087 | .96 | .167 |
Other | .88 | .003 | .81 | <.001 | .88 | .001 | .90 | .003 |
No Classification | .78 | <.001 | .83 | <.001 | .84 | <.001 | .83 | <.001 |
Group | Reference | Reference | Reference | Reference | ||||
Any Hospital Practice | ||||||||
Yes | 1.04 | .072 | 1.08 | .001 | .97 | .272 | .99 | .664 |
No | Reference | Reference | Reference | Reference | ||||
Antipsychotic Volume | ||||||||
1st quartile | .34 | <.001 | .39 | <.001 | .33 | <.001 | .28 | <.001 |
2nd quartile | .40 | <.001 | .46 | <.001 | .38 | <.001 | .35 | <.001 |
3rd quartile | .51 | <.001 | .55 | <.001 | .52 | <.001 | .47 | <.001 |
4th quartile | Reference | Reference | Reference | Reference | ||||
Top 25 Medical School | ||||||||
Yes | .94 | .082 | .94 | .055 | .87 | .001 | .98 | .628 |
No | Reference | Reference | Reference | Reference | ||||
Foreign Medical Graduate | ||||||||
Yes | 1.13 | <.001 | 1.13 | <.001 | 1.09 | .005 | 1.15 | <.001 |
No | Reference | Reference | Reference | Reference |
Note: These data were obtained from IMS Health, Xponent™, 1996–2008. Hazard ratios are presented in this table, with p-values provided in parentheses. A hazard ratio greater than 1.00 suggests that a physician with that characteristic was faster to adopt the drug on average relative to the reference group (and adjusting for the other variables in the model), while a hazard ratio less than 1.00 suggests that a physician with that characteristic was slower to adopt the drug on average relative to the reference group. These models also include for state fixed effects and variables characterizing the population residing in the zip code of the physician’s practice using data from the 2002 Area Resource File (percent black, percent Hispanic, percent enrolled in an HMO, percent who have completed high school, and percent 65 years or older).