Table 2.

Final Logistic Regression Model: Factors Associated With Inappropriate Use and Substitution

	Inappropriate Use		Substitution
Factors	Adjusted OR* (95% CI)	P Value	Adjusted OR* (95% CI)	P Value
Health insurance	—	—	1.86 (1.00 to 3.45)	.049
(no insurance = 1, have insurance = 0)
Back pain symptom	0.34 (0.16 to 0.74)	.008	0.29 (0.12 to 0.72)	.009
(no = 0, yes = 1)
History of UTI	0.49 (0.30 to 0.80)	.008	0.37 (0.22 to 0.61)	.000
(no = 0, yes = 1)
Previous use of Rx phenazopyridine	0.40 (0.25 to 0.63)	.000	0.48 (0.30 to 0.76)	.003
(no = 0, yes = 1)
Influenced by friend/family's advice	1.25 (1.05 to 1.47)	.012	—	—
(strongly disagree = 1, strongly agree = 4)
Little time to see the doctor	1.57 (1.26 to 1.96)	.000	1.89 (1.50 to 2.38)	.000
(strongly disagree = 1, strongly agree = 4)
Knowledge of phenazopyridine's action	0.52 (0.34 to 0.80)	.004	0.45 (0.27 to 0.77)	.005
(incorrect = 0, correct = 1)

^*Adjusted for the effects of other variables in the model.

Exploratory modeling for inappropriate use included 16 variables: gender, frequency, incontinence, fever, back pain, genital discharge, history of UTI, previous use of prescription phenazopyridine, friend's or family's advice, drug cheaper than provider visit, no time to see provider, waiting too long for provider appointment, health insurance, education, duration of symptoms, and knowledge of phenazopyridine's action. Exploratory modeling for substitution included 20 variables: gender, urinary burning, incontinence, dribbling, back pain, swelling, genital discharge, history of UTI, previous use of phenazopyridine, friend's or family's advice, drug cheaper than provider visit, no time to see provider, dislike provider, health insurance, income, education, duration of symptoms, ethnicity, knowledge of phenazopyridine's action.

OR, odds ratio; CI, confidence interval; Rx, prescription.