Table 2.
Baseline Comparisons between Subjects Who Completed Follow-up and Those Who Withdrew, Withheld DNA Sample or Did Not View Results, or Were Lost to Follow-up.*
| Variable | Completed Follow-up | Withdrew† | P Value | Withheld Sample or Did Not View Results | P Value | Viewed Results but Lost to Follow-up | P Value |
|---|---|---|---|---|---|---|---|
| No. of subjects | 2037 | 55 | NA | 223 | NA | 1310 | NA |
| Female sex (%) | 55.3 | 67.3 | 0.08 | 53.4 | 0.58 | 49.3 | 0.001 |
| Age (yr) | 0.49 | 0.54 | 0.008 | ||||
| Mean | 46.7±12.0 | 45.6±13.6 | 46.2±11.2 | 45.6±11.6 | |||
| Range | 19–85 | 21–71 | 22–82 | 19–85 | |||
| Income ($) | 0.02 | 0.02 | 0.009 | ||||
| Median | 100,000–149,999 | 100,000–149,999 | 100,000–149,999 | 150,000–199,999 | |||
| Modal | 100,000–149,999 | 50,000–99,999 | 100,000–149,999 | 100,000–149,999 | |||
| Median educational level | Some postgraduate education | Graduate of 4-yr college | 0.04 | Graduate of 4-yr college | <0.001 | Graduate of 4-yr college | 0.001 |
| White race (%)‡ | 84.2 | 63.6 | <0.001 | 69.1 | <0.001 | 76.6 | <0.001 |
| Scripps Health employee (%) | 23.6 | 41.8 | 0.002 | 19.7 | 0.20 | 16.5 | <0.001 |
| Anxiety score§ | 0.04 | 0.58 | 0.01 | ||||
| Mean | 35.2±9.6 | 37.8±9.5 | 35.8±10.2 | 36.2±10.0 | |||
| Median | 34.0 | 37.0 | 35.0 | 35.0 | |||
| Range | 20–72 | 22–57 | 20–65 | 20–74 | |||
| Dietary fat score¶ | 0.02 | 0.97 | 0.34 | ||||
| Mean | 16.0±7.9 | 13.6±8.6 | 16.0±7.8 | 15.8±8.2 | |||
| Median | 15.0 | 12.0 | 15.0 | 15.0 | |||
| Range | 0–51 | 0–34 | 1–41 | 0–54 | |||
| Exercise score | 0.67 | 0.10 | 0.005 | ||||
| Mean | 28.6±23.0** | 27.5±22.3 | 26.7±22.2†† | 27.7±25.3‡‡ | |||
| Median | 24.0** | 23.8 | 21.0†† | 22.1‡‡ | |||
| Range | 0–246** | 0–112 | 0–110†† | 0–238 ‡‡ |
Plus–minus values are means ±SD. P values are for comparisons with the group of subjects who completed follow-up. P values for comparisons of sex, race, and employment by Scripps Health were calculated by means of Pearson's chi-square test; those for age by means of independent samples t-test; and those for income, education, and scores on assessments of anxiety, dietary fat intake, and exercise by means of the Mann–Whitney U test. NA denotes not applicable because no statistical test was performed.
Of the 89 subjects who withdrew, only 55 completed a baseline assessment.
Race was self-reported.
Anxiety was assessed with the 20-item subscale of the Spielberger State–Trait Anxiety Inventory; scores range from 20 to 80, with higher scores indicating higher anxiety. A score of 39 or less is considered to indicate low anxiety. A difference of 12 points or more on this measure is considered to indicate a reliable and clinically meaningful change.
Dietary fat intake was measured with the 17-item Block Dietary Fat Screener; scores range from 0 to 68, with higher scores indicating higher fat intake. A difference of 11 points or more on this measure is considered to indicate a reliable and clinically meaningful change.
Exercise and physical activity were measured with the Godin Leisure-Time Exercise Questionnaire; scores range from 0 to 246, with higher scores indicating greater physical activity (i.e., a greater number of metabolic-equivalent hours per week). A difference of 29 points or more on this measure is considered to indicate a reliable and clinically meaningful change.
A total of 1943 subjects were included in this category.
A total of 215 subjects were included in this category.
A total of 1272 subjects were included in this category.