. 2014 Sep;12(5):402–407. doi: 10.1370/afm.1683

Table 2.

Socioeconomic Status as a Predictor of Obstructive Airway Disease–Related Hospitalization Across Models

Income Quintile	Odds Ratio (95% Confidence Limit)
Income Quintile	Model A	Model B	Model C	Model D
Q1 (lowest)	3.72^a (2.81, 4.92)	3.10^a (2.33, 4.13)	3.15^a (2.35, 4.21)	2.93^a (2.19, 3.93)
Q2	2.61^a (1.95, 3.50)	2.45^a (1.82, 3.30)	2.61^a (1.93, 3.53)	2.51^a (1.86, 3.40)
Q3	1.70^a (1.24, 2.33)	1.57^a (1.14, 2.16)	1.60^a (1.15, 2.21)	1.54^a (1.11, 2.13)
Q4	1.38 (0.99, 1.91)	1.33 (0.95, 1.85)	1.43^a (1.02, 2.01)	1.41^a (1.01, 1.98)
Q5 (highest)^b	1.0	1.0	1.0	1.0

P <.05.

Reference group for odds ratio calculation.

Notes: model A = income quintile only; model B = income quintile + patient demographics; model C = income quintile + patient demographics + ambulatory care use; and model D = income quintile + patient demographics + ambulatory care use + usual physician characteristics.