Table 1.
Demographic Information of the Study Subjects Enrolled in a Population-based Case-control Study of Esophageal Squamous Cell Carcinoma, Taixing, China, 2010–2013, stratified by gender
| Variables | Men | Women | P value for comparing male and female controls b | ||||
|---|---|---|---|---|---|---|---|
| Controls (N=1373) N (%) |
Cases (N=962) N (%) |
P value a | Controls (N=619) N (%) |
Cases (N=456) N (%) |
P value a | ||
| Age at interview (mean±SD, years) | 65.6±8.4 | 65.3±8.5 | 0.228 | 67.6±9.4 | 69.4±7.6 | 0.024 | 0.0001 |
| Age group | |||||||
| 40-49 | 53 (3.86) | 30 (3.12) | 0.134 | 29 (4.68) | 5 (1.1) | <0.001 | <0.001 |
| 50-59 | 277 (20.17) | 215 (22.35) | 90 (14.54) | 35 (7.68) | |||
| 60-69 | 586 (42.68) | 417 (43.35) | 209 (33.76) | 187 (41.01) | |||
| 70-79 | 407 (29.64) | 252 (26.2) | 237 (38.29) | 187 (41.01) | |||
| 80-84 | 50 (3.64) | 48 (4.99) | 54 (8.72) | 42 (9.21) | |||
| Marital status | |||||||
| Unmarried | 63 (4.59) | 55 (5.72) | 0.278 | 5 (0.81) | 2 (0.44) | 0.575 | <0.001 |
| Married | 1160 (84.49) | 790 (82.12) | 428 (69.14) | 307 (67.32) | |||
| Divorced/Widowed | 150 (10.92) | 117 (12.16) | 186 (30.05) | 147 (32.24) | |||
| Occupation | |||||||
| Farmer | 713 (51.93) | 517 (53.74) | 0.673 | 547 (88.37) | 431 (94.52) | 0.002 | <0.001 |
| Worker | 356 (25.93) | 243 (25.26) | 45 (7.27) | 17 (3.73) | |||
| Service/Clerk/Professional/Administrator | 304 (22.14) | 202 (21) | 27 (4.36) | 8 (1.75) | |||
| Education | |||||||
| Illiteracy | 171 (12.45) | 169 (17.57) | 0.002 | 369 (59.61) | 329 (72.15) | <0.001 | <0.001 |
| Primary school | 589 (42.9) | 419 (43.56) | 171 (27.63) | 109 (23.9) | |||
| Junior high school | 463 (33.72) | 285 (29.63) | 67 (10.82) | 16 (3.51) | |||
| High school and above | 150 (10.92) | 89 (9.25) | 12 (1.94) | 2 (0.44) | |||
| Family wealth score | |||||||
| Q1-lowest | 288 (20.98) | 282 (29.31) | <0.001 | 120 (19.39) | 122 (26.75) | 0.024 | 0.351 |
| Q2 | 234 (17.04) | 166 (17.26) | 119 (19.22) | 89 (19.52) | |||
| Q3 | 289 (21.05) | 216 (22.45) | 145 (23.42) | 106 (23.25) | |||
| Q4 | 297 (21.63) | 178 (18.5) | 132 (21.32) | 84 (18.42) | |||
| Q5 | 265 (19.3) | 120 (12.47) | 103 (16.64) | 55 (12.06) | |||
| BMI at 10 years ago | |||||||
| <18.5 (Underweight) | 57 (4.15) | 71 (7.38) | <0.001 | 53 (8.56) | 61 (13.38) | 0.005 | <0.001 |
| 18.5-24) (Normal) | 864 (62.93) | 652 (67.78) | 341 (55.09) | 251 (55.04) | |||
| [24, 28) (Overweight) | 367 (26.73) | 195 (20.27) | 178 (28.76) | 127 (27.85) | |||
| ≥ 28 (Obese) | 83 (6.05) | 41 (4.26) | 46 (7.43) | 16 (3.51) | |||
| Missing | 2 (0.15) | 3 (0.31) | 1 (0.16) | 1 (0.22) | |||
| Adult height (cm, male | female) | |||||||
| ≤ 162 | ≤ 152 | 500 (36.42) | 164 (17.05) | <0.001 | 244 (39.42) | 66 (14.47) | <0.001 | <0.001 |
| (162, 170] | (152, 156] | 637 (46.39) | 513 (53.33) | 153 (24.72) | 154 (33.77) | |||
| (170-174] | (156, 160] | 118 (8.59) | 131 (13.62) | 141 (22.78) | 152 (33.33) | |||
| >174 | >160 | 116 (8.45) | 151 (15.7) | 80 (12.92) | 83 (18.2) | |||
| Missing | 2 (0.15) | 3 (0.31) | 1 (0.16) | 1 (0.22) | |||
| Frequency of tooth brushing per day | |||||||
| < 2 | 903 (65.77) | 758 (78.79) | <0.001 | 387 (62.52) | 352 (77.19) | <0.001 | 0.141 |
| ≥ 2 | 452 (32.92) | 174 (18.09) | 225 (36.35) | 87 (19.08) | |||
| Missing | 18 (1.31) | 30 (3.12) | 7 (1.13) | 17 (3.73) | |||
| Sum of missing and filled teeth | |||||||
| None | 370 (26.95) | 245 (25.47) | 0.177 | 130 (21.00) | 59 (12.94) | 0.001 | <0.001 |
| < 6 | 514 (37.44) | 327 (33.99) | 203 (32.79) | 132 (28.95) | |||
| ≥ 6 | 471 (34.3) | 358 (37.21) | 278 (44.91) | 240 (52.63) | |||
| Missing | 18 (1.31) | 32 (3.33) | 8 (1.29) | 25 (5.48) | |||
| Smoking pack-years | |||||||
| Never | 299 (21.78) | 153 (15.9) | <0.001 | 585 (94.51) | 413 (90.57) | 0.875 | <0.001 |
| ≤ 30 | 522 (38.02) | 327 (33.99) | 20 (3.23) | 15 (3.29) | |||
| > 30 | 531 (38.67) | 438 (45.53) | 4 (0.65) | 4 (0.88) | |||
| Missing | 21 (1.53) | 44 (4.57) | 10 (1.62) | 24 (5.26) | |||
| Alcohol drinking intensity (g/day) | |||||||
| Never | 584 (42.53) | 235 (24.43) | <0.001 | 574 (92.73) | 400 (87.72) | 0.306 | <0.001 |
| ≤ 80 | 373 (27.17) | 289 (30.04) | 31 (5.01) | 31 (6.8) | |||
| > 80 | 395 (28.77) | 397 (41.27) | 3 (0.48) | 1 (0.22) | |||
| Missing | 21 (1.53) | 41 (4.26) | 11 (1.78) | 24 (5.26) | |||
| Tea drinking temperature | |||||||
| Never | 858 (62.49) | 493 (51.25) | <0.001 | 578 (93.38) | 420 (92.11) | 0.199 | <0.001 |
| Warm | 206 (15) | 150 (15.59) | 19 (3.07) | 11 (2.41) | |||
| Hot | 213 (15.51) | 176 (18.3) | 8 (1.29) | 1 (0.22) | |||
| Very Hot | 76 (5.54) | 102 (10.6) | 4 (0.65) | 2 (0.44) | |||
| Missing | 20 (1.46) | 41 (4.26) | 10 (1.62) | 22 (4.82) | |||
| Family history of esophageal cancer among first-degree relatives | |||||||
| No | 1106 (80.55) | 632 (65.7) | <0.001 | 499 (80.61) | 296 (64.91) | <0.001 | 0.905 |
| Yes | 252 (18.35) | 298 (30.98) | 112 (18.09) | 141 (30.92) | |||
| Missing | 15 (1.09) | 32 (3.33) | 8 (1.29) | 19 (4.17) | |||
| Number of risk factors c | |||||||
| 0 risk factor | 8 (0.58) | 0 (0) | <0.001 | 1 (0.16) | 0 (0) | <0.001 | <0.001 |
| 1 risk factor | 48 (3.5) | 13 (1.35) | 7 (1.13) | 1 (0.22) | |||
| 2 risk factors | 167 (12.16) | 34 (3.53) | 32 (5.17) | 5 (1.1) | |||
| 3 risk factors | 335 (24.4) | 116 (12.06) | 81 (13.09) | 16 (3.51) | |||
| 4 risk factors | 402 (29.28) | 223 (23.18) | 184 (29.73) | 72 (15.79) | |||
| 5 risk factors | 263 (19.16) | 267 (27.75) | 197 (31.83) | 153 (33.55) | |||
| 6 risk factors | 96 (6.99) | 198 (20.58) | 94 (15.19) | 133 (29.17) | |||
| 7 risk factors | 22 (1.6) | 50 (5.2) | 10 (1.62) | 47 (10.31) | |||
| 8 risk factors | 2 (0.15) | 11 (1.14) | 4 (0.65) | 2 (0.44) | |||
| Missing | 30 (2.18) | 50 (5.2) | 9 (1.45) | 27 (5.92) | |||
Abbreviations: SD standard deviation, N number, BMI body mass index
a P values were derived using Kruskal–Wallis test for continuous variables and Chi-squared test or Fisher exact test for categorical variables, after excluding the corresponding missing values
b P values were for comparisons between male and female controls
c risk factor were defined as low education level (illiteracy, primary school), family wealth score (Q1, Q2, Q3), BMI (underweight), tooth brushing times (< 2), smoking pack-years (> 0), alcohol consumption intensity (> 0), tea drinking temperature (hot, very hot), and family history of esophageal cancer among first-degree relatives (yes), occupation (farmer), sum of missing and filled teeth (> 0), which were defined based on results from univariate analysis (P < 0.05)