Table 1.
Difference in Patient Characteristics Between Patients Treated With EP Versus CP in the Observational Data Set and in Patients Who Were Matched by a Propensity Score
| Characteristic | Observational Data Set (n = 1,842) |
Propensity Score–Matched Data Set (n = 762) |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| EP (n = 499) |
CP (n = 1,343) |
Standard Difference | P | EP (n = 381) |
CP (n = 381) |
Standard Difference | P | |||||
| No. of Patients | % | No. of Patients | % | No. of Patients | % | No. of Patients | % | |||||
| Age, years | 0.50 | < .001 | 0.06 | .3999 | ||||||||
| Mean | 61.3 | 65.5 | 62.0 | 62.4 | ||||||||
| SD | 7.6 | 9 | 7.4 | 7.9 | ||||||||
| Era of diagnosis | 0.24 | < .001 | 0 | 1 | ||||||||
| 2001-2004 | 129 | 25.9 | 477 | 35.5 | 94 | 50 | 94 | 50 | ||||
| 2005-2007 | 194 | 38.9 | 393 | 29.3 | 152 | 50 | 152 | 50 | ||||
| 2008-2010 | 176 | 35.3 | 473 | 35.2 | 135 | 50 | 135 | 50 | ||||
| Stage IIIB | 281 | 56.3 | 759 | 56.5 | < 0.01 | .9379 | 189 | 49.6 | 204 | 53.5 | 0.8 | .2769 |
| Histology | 0.11 | .2112 | 0.07 | .8158 | ||||||||
| Adenocarcinoma | 110 | 22 | 252 | 18.8 | 82 | 21.5 | 85 | 22.3 | ||||
| NOS | 146 | 29.3 | 378 | 28.1 | 107 | 28.1 | 112 | 29.5 | ||||
| Other | 3 | 0.6 | 15 | 1.1 | 3 | 0.8 | 5 | 1.3 | ||||
| Squamous cell | 240 | 48.1 | 698 | 52 | 189 | 49.6 | 179 | 48.3 | ||||
| Hemoglobin at baseline, g/dL | 0.11 | .0378 | 0.07 | .3164 | ||||||||
| Mean | 12.9 | 12.7 | 13.0 | 13.1 | ||||||||
| SD | 1.8 | 1.8 | 1.8 | 1.7 | ||||||||
| Platelets at baseline, × 109/L | 0.08 | .1393 | 0.03 | .7169 | ||||||||
| Mean | 331.2 | 321.2 | 324.4 | 321.1 | ||||||||
| SD | 124.0 | 123.3 | 118.9 | 126.4 | ||||||||
| eGFR at baseline, mL/min | 0.16 | .0024 | 0.01 | .9721 | ||||||||
| Mean | 87.3 | 83.7 | 85.7 | 85.7 | ||||||||
| SD | 22.0 | 23.1 | 22.1 | 21.8 | ||||||||
| Baseline serum albumin, g/dL | 0.11 | .0586 | 0.02 | .8084 | ||||||||
| Mean | 3.6 | 3.5 | 3.6 | 3.6 | ||||||||
| SD | 0.6 | 0.6 | 0.6 | 0.6 | ||||||||
| Weight loss, % | 0.25 | < .001 | 0.04 | .7438 | ||||||||
| Mean | 2.9 | 4.5 | 2.9 | 2.8 | ||||||||
| SD | 6.3 | 6.5 | 6.4 | 5.8 | ||||||||
| NCI combined index > 2 | 46 | 9.3 | 230 | 17.2 | 0.24 | < .001 | 39 | 10.2 | 30 | 7.9 | 0.08 | .2559 |
| No. of prior hospitalizations in the year before treatment | 0.07 | .1601 | 0.07 | .3563 | ||||||||
| Mean | 0.9 | 0.8 | 0.9 | 0.8 | ||||||||
| SD | 1.0 | 0.9 | 1.0 | 0.9 | ||||||||
Abbreviations: CP, carboplatin-paclitaxel; eGFR, estimated glomerular filtration rate; EP, etoposide-cisplatin; NCI, National Cancer Institute; NOS, not otherwise specified; SD, standard deviation.