Table 1.
Baseline characteristics of study population by treatment groups in mail and telephone randomized trials
| Mail trial | Telephone trial | |||||
|---|---|---|---|---|---|---|
| Characteristics 1 | All participants (N = 332) | Personalized envelope (N = 166) | Business envelope (N = 166) | All participants (N = 171) | Study name in message (N = 86) | P.I. name in message (N = 85) |
| Participant demographics and last contact | ||||||
| Age, mean (SD) | 48.8 (15.0) | 48.2 (15.4) | 49.4 (14.7) | 46.0 (14.7) | 46.7 (14.0) | 45.3 (15.5) |
| Male, n (%) | 160 (48) | 77 (46) | 83 (50) | 84 (49) | 44 (51) | 40 (47) |
| Minority2, n (%) | 64 (20) | 27 (17) | 37 (23) | 42 (26) | 19 (23) | 23 (28) |
| Employment status3 | ||||||
| Employed (full- or part-time), n (%) | 97 (30) | 41 (25) | 56 (34) | 52 (31) | 32 (38) | 20 (24) |
| Unemployed, n (%) | 79 (24) | 43 (26) | 36 (22) | 43 (26) | 15 (18) | 28 (34) |
| Retired or disabled, n (%) | 151 (46) | 80 (49) | 71 (44) | 72 (43) | 37 (44) | 35 (42) |
| Months since last contact, mean (SD) | 33.7 (7.3) | 34.2 (7.2) | 33.3 (7.4) | 33.5 (7.5) | 35.2 (7.1) | 31.7 (7.5) |
| Physical and mental health status 3 , mean (SD) | ||||||
| FPI overall score | 2.0 (0.7) | 2.0 (0.7) | 2.0 (0.7) | 1.9 (0.7) | 1.9 (0.8) | 2.0 (0.7) |
| FPI body care subscale score | 2.5 (0.6) | 2.5 (0.6) | 2.5 (0.6) | 2.5 (0.7) | 2.4 (0.7) | 2.6 (0.6) |
| FPI maintaining household subscale score | 1.9 (0.9) | 1.9 (0.9) | 1.9 (0.9) | 1.9 (0.9) | 1.8 (1.0) | 1.9 (0.8) |
| FPI physical exercise subscale score | 1.6 (0.9) | 1.6 (0.9) | 1.7 (0.9) | 1.6 (0.9) | 1.6 (1.0) | 1.6 (0.9) |
| SF-36 Physical Component Summary | 40.5 (12.5) | 40.7 (12.4) | 40.3 (12.7) | 40.5 (12.8) | 40.0 (13.3) | 41.1 (12.3) |
| SF-36 Mental Component Summary | 44.9 (14.8) | 45.0 (14.4) | 44.6 (15.2) | 42.1 (14.8) | 41.4 (14.3) | 42.9 (15.3) |
| EQ-5D visual analogue scale | 69.1 (22.7) | 70.3 (22.3) | 67.9 (23.0) | 67.4 (23.7) | 65.5 (24.2) | 69.2 (23.3) |
| EQ-5D utility score | 0.7 (0.2) | 0.7 (0.2) | 0.7 (0.2) | 0.7 (0.3) | 0.7 (0.3) | 0.7 (0.2) |
| MMSE score | 25.6 (1.9) | 25.5 (2.0) | 25.7 (1.8) | 25.5 (2.2) | 25.4 (2.6) | 25.6 (1.7) |
| HADS-depression subscale score | 6.0 (4.9) | 5.9 (4.9) | 6.2 (5.0) | 6.7 (4.9) | 6.8 (5.1) | 6.6 (4.7) |
| HADS-anxiety subscale score | 7.0 (5.1) | 7.0 (5.3) | 7.1 (4.9) | 8.0 (5.0) | 7.9 (4.7) | 8.0 (5.2) |
| IES-R score | 1.0 (1.0) | 1.0 (1.0) | 1.0 (1.0) | 1.1 (1.0) | 1.1 (1.0) | 1.2 (1.0) |
| FACIT score | 62.3 (18.6) | 62.3 (20.0) | 62.2 (17.1) | 60.2 (16.9) | 59.4 (15.6) | 61.1 (18.0) |
Abbreviations: SD (Standard Deviation), FPI (Functional Performance Inventory), SF-36 (Short Form-36 Health Survey), EQ-5D (EuroQol Five Dimensions Questionnaire), MMSE (Mini-Mental State Examination), HADS (Hospital Anxiety and Depression Scale), IES-R (Impact of Event Scale-Revised), FACIT (Functional Assessment of Chronic Illness Therapy).
1Missing values for each variable: months since last contact (1, 1), white (12, 7), employment (5, 4), all FPI scores (10, 7), SF-36 Physical and Mental Component Summaries (17, 10), EQ-5D VAS (10, 7), EQ-5D utility (9, 6), MMSE (20, 12), HADS subscales (14, 9), IES-R (16, 11), FACIT (16, 10).
2Minority race includes African American, Asian, American Indian and Alaskan Native.
3Status as at last contact with research participant.