Table 4.

Changes in Exacerbation and Hospitalization Rates Between Pseudomonas aeruginosa Culture-Positive and Culture-Negative Groups Using Segmented Regression Analysis, Buffalo, New York, April 1994–June 2014^a,b

Outcome	Group	Baseline Trend (per 100 person-months)		Change in Level		Trend Change After Month 12 (per 100 person-months)
		Coefficient (SE)	P	Coefficient (SE)	P	Coefficient (SE)	P
Exacerbation Rate	PA culture-positive	0.537 (0.339)	.12	1.34 (3.27)	.69	−1.19 (0.472)	.02
	PA culture-negative	−0.356 (0.458)	.44	−1.99 (3.02)	.52	0.225 (0.405)	.58
	Difference	0.709 (0.434)	.11	2.70 (4.18)	.52	−1.18 (0.603)	.06
Hospitalization Rate	PA culture-positive	0.247 (0.281)	.39	1.83 (2.71)	.50	−0.312 (0.391)	.43
	PA culture-negative	−0.533 (0.289)	.07	−2.84 (1.90)	.15	0.343 (0.255)	.19
	Difference	0.522 (0.263)	.06	3.33 (2.54)	.20	−0.561 (0.366)	.14

Abbreviations: PA, P aeruginosa; SE, standard error.

^aEach model is adjusted for age and forced expiratory volume in 1 second (FEV₁)%.

^bSignificant results are shown in boldface.