Table 1 Sample Characteristics and Selection Bias Results
Baseline Variable | Attrition Samplea (n = 2691) | Analytic Sample (n = 1481) | t-test p-value |
|---|---|---|---|
Continuous Variables: Mean, SD | Mean SD | Mean SD | |
Age | 48.53 13.32 | 49.88 13.24 | −3.15 0.00 |
Range | 20~93 | 20~91 | |
Total Number of Comorbidities | 3.89 2.33 | 3.94 2.28 | −0.62 0.53 |
Range | 3.80~3.98 | 3.82~4.06 | |
Categorical Variables: N, % | N % | N % | chi2 p-value |
Respondent Type | |||
Patients | 2111 78.5% | 1212 81.8% | 14.57 0.00 |
Caregivers | 528 19.6% | 227 15.3% | |
Both patient and caregiver | 52 19.3% | 42 28.4% | |
Gender | |||
Male | 362 13.45 | 209 14.11 | 0.35 0.84 |
Female | 2320 86.21 | 1269 85.69 | |
Other | 5 0.19 | 3 0.2 | |
Co-morbidities | |||
Arthritis | 1057 39.28 | 632 42.67 | 4.52 0.03 |
Asthma | 498 18.51 | 294 19.85 | 1.12 0.29 |
Back Pain | 1538 57.15 | 855 57.73 | 0.10 0.76 |
Cancer | 1335 49.61 | 730 49.29 | 0.06 0.80 |
Depression | 1365 50.72 | 712 48.08 | 2.74 0.10 |
Diabetes | 317 11.78 | 168 11.34 | 0.17 0.68 |
Heart Disease | 218 8.10 | 110 7.43 | 0.57 0.45 |
High Blood Pressure | 719 26.72 | 429 28.97 | 2.57 0.11 |
Insomnia | 1210 44.96 | 652 44.02 | 0.45 0.50 |
Kidney Disease | 143 5.31 | 80 5.40 | 0.02 0.90 |
Liver Disease | 115 4.27 | 56 3.78 | 0.59 0.44 |
Lung Disease | 311 11.56 | 166 11.21 | 0.13 0.71 |
Stroke | 91 3.38 | 42 2.84 | 0.90 0.34 |
Ulcer or Stomach Disease | 439 16.31 | 207 13.98 | 3.88 0.05 |
Other | 1110 41.25 | 688 46.46 | 9.26 0.00 |
Marital Status | |||
Single (never married) | 368 13.68 | 211 14.25 | 1.61 0.90 |
Married | 1627 60.46 | 899 60.7 | |
Cohabitation /Domestic Partner | 159 5.91 | 100 6.75 | |
Divorced | 60 2.23 | 33 2.23 | |
Separated | 335 12.45 | 180 12.15 | |
Widowed | 104 3.86 | 52 3.51 | |
Missing | 38 1.41 | 6 0.41 | |
Ethnicity | |||
Not Hispanic or Latino | 2439 90.64 | 1379 93.11 | 4.87 0.03 |
Hispanic or Latino | 156 5.8 | 63 4.25 | |
Missing | 96 3.57 | 39 2.63 | |
Race | |||
American Indian or Alaskan Native | 80 2.97 | 35 2.36 | 1.32 0.25 |
Middle Eastern | 8 0.30 | 6 0.41 | 0.33 0.56 |
South Asian | 7 0.26 | 4 0.27 | 0.00 0.95 |
Other Asian | 30 1.11 | 13 0.88 | 0.53 0.47 |
Black or African-America | 142 5.28 | 59 3.98 | 3.48 0.06 |
Native Hawaiian, Other Pacific Islander | 16 0.59 | 7 0.47 | 0.26 0.61 |
White | 2413 89.67 | 1372 92.64 | 10.02 0.00 |
Education | |||
Less than High School | 58 2.16 | 16 1.08 | 43.92 0.00 |
Graduated From High School or GED | 714 26.53 | 299 20.19 | |
Some College or Technical School | 519 19.29 | 259 17.49 | |
Graduated from College | 803 29.84 | 484 32.68 | |
Postgraduate School or Degree | 536 19.92 | 390 26.33 | |
Missing | 61 2.27 | 33 2.23 | |
Employment Status at Baseline | |||
Working | 1271 47.23 | 705 47.6 | 9.80 0.02 |
Currently Not working | 365 13.56 | 156 10.53 | |
Retired (not due to ill health) | 323 12 | 199 13.44 | |
Disabled and/or retired due to health | 676 25.12 | 399 26.94 | |
Missing | 56 2.08 | 22 1.49 | |
Occupational Complexity (O*NET Job Zone) | |||
1: Little or No Preparation Needed | 115 4.27 | 60 4.05 | 21.53 0.00 |
2: Some Preparation Needed | 529 19.66 | 252 17.02 | |
3: Medium Preparation Needed | 877 32.59 | 439 29.64 | |
4: Considerable Preparation Needed | 704 26.16 | 440 29.71 | |
5: Extensive Preparation Needed | 271 10.07 | 203 13.71 | |
Missing | 195 7.25 | 87 5.87 | |
Income | |||
Less than $15,000 | 247 9.18 | 123 8.31 | 5.39 0.50 |
$15,001 to $30,000 | 387 14.38 | 201 13.57 | |
$30,001 to $50,000 | 461 17.13 | 250 16.88 | |
$50,001 to $100,000 | 727 27.02 | 432 29.17 | |
$100,001 to $150,000 | 319 11.85 | 189 12.76 | |
$150,001 to $200,000 | 101 3.75 | 70 4.73 | |
Over $200,000 | 88 3.27 | 46 3.11 | |
Missing | 361 13.42 | 170 11.48 | |
Difficulty Paying Billsb | |||
Not at all difficult | NA | 528 35.65 | |
Slightly difficult | NA | 334 22.55 | |
Somewhat difficult | NA | 264 17.83 | |
Very difficult | NA | 148 9.99 | |
Extremely difficult | NA | 142 9.59 | |
Missing | NA | 65 4.39 | |