Table 4.

Income difference in occurring high medical expenditure

			Unit: USD
Variables	Estimate§	Std. Error	p-value
≥ at twice the average medical expense (n = 1,956)
Year (reference: 2007)
2008	556	44.6	0.1818
2009	47	58.6	0.9315
2010	672	49.8	0.1482
2011	791	55.7	0.1283
Case (reference: non-occurrence household)
Occurrence household	−1,435	67.6	0.0230
Interaction term (year x Case)
2008	−1,353	51.5	0.0049
2009	−888	67.5	0.1591
2010	−770	57.3	0.1503
2011	−434	64.0	0.4672
≥ at four times the average medical expense (n = 696)
Year (reference: 2007)
2008	2,597	103.4	0.0073
2009	2,605	130.7	0.0330
2010	835	107.0	0.4029
2011	1,212	113.6	0.2532
Case (reference: non-occurrence household)
Occurrence household	−2,373	147.6	0.0453
Interaction term (year x Case)
2008	−2,233	119.3	0.0453
2009	−2,862	150.6	0.0420
2010	−1,790	123.1	0.1195
2011	−1,342	130.5	0.2710
≥ at five times the average medical expense (n = 500)
Year (reference: 2007)
2008	2,204	82.9	0.0046
2009	2,340	103.4	0.0157
2010	1,476	107.0	0.1403
2011	1,098	120.8	0.3306
Case (reference: non-occurrence household)
Occurrence household	−2,553	137.0	0.0464
Interaction term (year x Case)
2008	−2,147	95.7	0.0167
2009	−2,385	119.0	0.0323
2010	−2,749	123.0	0.0170
2011	−1,840	138.7	0.1556

§ Adjusted odds ratio from multiple regression analysis with all of the variables in Table 1