Table 1 Characteristics of 45 and Up participants according to response to follow-up survey
From: On the impact of nonresponse in logistic regression: application to the 45 and Up study
Baseline characteristics | Moved n = 347 (%) (1.7%) | Responded n = 20730 (%) (67.3%) | Total n = 30799 | OR (95% CI) |
|---|---|---|---|---|
Gender | ||||
 Male | 157 (1.7) | 9232 (66.5) | 13888 | Ref |
 Female | 190 (1.7) | 11498 (68.0) | 16911 | 1.11 (1.05–1.17) |
Age (yrs) | ||||
 45–54 | 6 (0.1) | 6577 (66.0) | 9960 | Ref |
 55–64 | 59 (0.7) | 8696 (70.4) | 12350 | 1.22 (1.15–1.30) |
 65–74 | 132 (3.4) | 3920 (67.5) | 5805 | 1.12 (1.02–1.23) |
 75+ | 150 (9.8) | 1537 (57.3) | 2684 | 0.81 (0.72–0.91) |
Highest qualification | ||||
 None | 34 (2.4) | 1421(52.1) | 2725 | Ref |
 Year 10 | 82 (2.1) | 3950 (62.8) | 6294 | 1.25 (1.14–1.37) |
 Year 12 | 29 (1.4) | 2019 (63.7) | 3171 | 1.45 (1.30–1.62) |
 Trade | 35 (1.9) | 1855 (62.7) | 2957 | 1.34 (1.20–1.50) |
 Cert./diploma | 86 (1.7) | 5042 (70.8) | 7125 | 1.78 (1.62–1.96) |
 Tertiary | 81 (1.3) | 6443 (75.6) | 8527 | 2.29 (2.07–2.53) |
Area remoteness | ||||
 Major cities | 192 (1.8) | 10885 (66.1) | 16460 | Ref |
 Inner regional | 135 (1.7) | 7831(69.0) | 11352 | 1.06 (1.00–1.12) |
 Outer regional/remote/very remote | 20 (1.0) | 2014 (67.4) | 2987 | 1.06 (0.97–1.16) |
Country of birth | ||||
 Australia | 261 (1.6) | 16237 (69.1) | 23492 | Ref |
 NW Europe | 65 (2.5) | 2652 (68.8) | 3857 | 0.97 (0.89–1.04) |
 S & E Europe | 5 (1.4) | 356 (48.8) | 730 | 0.67 (0.56–0.79) |
 Middle East | 0 (0.0) | 106 (42.6) | 249 | 0.50 (0.38–0.66) |
 SE Asia | 4 (2.0) | 204 (44.9) | 454 | 0.47 (0.38–0.58) |
 NE Asia | 0 (0.0) | 168 (46.9) | 358 | 0.56 (0.44–0.70) |
 S & Central Asia | 0 (0.0) | 102 (50.2) | 203 | 0.50 (0.37–0.67) |
 America | 1 (0.4) | 223 (60.4) | 369 | 0.62 (0.50–0.78) |
 Sub Saharan Africa | 4 (2.3) | 177 (58.8) | 301 | 0.57 (0.45–0.72) |
 Oceania | 7 (1.4) | 491 (64.0) | 767 | 0.76 (0.65–0.89) |
Speak a language other than English at home | ||||
 No | 329 (1.7) | 19453 (68.9) | 28234 | Ref |
 Yes | 18 (1.4) | 1277 (49.8) | 2565 | 0.68(0.61–0.76) |
Marital status | ||||
 Single | 19 (1.9) | 1013 (63.2) | 1604 | Ref |
 Married/de facto | 252 (1.5) | 16368 (68.5) | 23908 | 1.13 (1.01–1.27) |
 Widowed/divorced/separated | 76 (2.3) | 3349 (63.3) | 5287 | 1.01 (0.89–1.14) |
Work status | ||||
 FT/self-employed | 21 (0.2) | 8996 (68.5) | 13126 | Ref |
 PT | 20 (0.6) | 3148 (71.2) | 4422 | 1.18 (1.08–1.27) |
 Fully retired | 276 (4.5) | 6162 (66.7) | 9243 | 1.34 (1.23–1.46) |
 Partially retired | 13 (1.5) | 865 (74.3) | 1164 | 1.35 (1.17–1.55) |
 Disabled/sick | 3 (0.7) | 442 (51.3) | 862 | 1.07 (0.91–1.26) |
 Unemployed/look after home/study/unpaid | 14 (1.3) | 1117 (56.4) | 1982 | 0.86 (0.77–0.96) |
Income category | ||||
  < $20,000 | 101 (3.4) | 2951 (58.7) | 5027 | Ref |
 $20,000–$40,000 | 97 (2.6) | 3696 (67.1) | 5512 | 1.11 (1.02–1.21) |
 $40,000–$70,000 | 61 (1.3) | 4598 (70.6) | 6517 | 1.23 (1.12–1.34) |
  > $70,000 | 34 (0.5) | 6890 (73.3) | 9394 | 1.25 (1.13–1.38) |
 Prefer not to answer | 54 (2.1) | 2595 (59.7) | 4349 | 0.84 (0.77–0.92) |
Dwelling type | ||||
 House/house on farm | 272 (1.5) | 18419 (68.0) | 27086 | Ref |
 Flat/unit/apart. | 64 (3.2) | 2030 (62.8) | 3231 | 0.92 (0.85–1.00) |
 Mobile home/other | 11 (3.9) | 281 (58.3) | 482 | 0.86 (0.71–1.04) |
Carer status | ||||
 No | 296 (1.6) | 18427 (67.8) | 27178 | Ref |
 Yes | 51 (2.2) | 2303 (63.6) | 3621 | 0.88 (0.82–0.95) |
Self-rated health | ||||
 Excellent | 37 (1.0) | 3893 (74.6) | 5219 | Ref |
 Very good | 116 (1.4) | 8420 (70.9) | 11876 | 0.88 (0.82–0.95) |
 Good | 133 (2.1) | 6436 (64.5) | 9984 | 0.74 (0.68–0.80) |
 Fair | 52 (3.0) | 1729 (54.5) | 3170 | 0.58 (0.52–0.65) |
 Poor | 9 (3.6) | 252 (45.8) | 550 | 0.53 (0.43–0.65) |
Functional limitation (fl) | ||||
 No fl | 163 (1.0) | 15710 (69.8) | 22510 | Ref |
 Slight fl | 95 (3.4) | 2802 (65.8) | 4261 | 1.04 (0.96–1.12) |
 Moderate fl | 35 (3.1) | 1119 (59.2) | 1891 | 0.94 (0.85–1.05) |
 Significant fl | 35 (5.1) | 686 (54.1) | 1267 | 0.81 (0.71–0.92) |
 Severe fl | 19 (4.6) | 413 (47.5) | 870 | 0.72 (0.61–0.84) |
DSSI in quartiles | ||||
 1 | 179 (2.1) | 8383 (69.6) | 12039 | Ref |
 2 | 62 (1.2) | 5063 (68.2) | 7428 | 0.98 (0.92–1.05) |
 3 | 50 (1.4) | 3611 (66.3) | 5447 | 0.96 (0.90–1.03) |
 4 | 56 (1.5) | 3673 (62.4) | 5885 | 0.89 (0.83–0.96) |