Calibration equations
Quadratic equations were used for the calibration of self-reported weight and height against
clinical measures. Clinically measured parameters were considered criterion and self-reported
parameters were treated as predictor variables. The constants and coefficients were obtained
from clinical assessments at baseline which included both clinically measured and selfreported parameters. They were then used to calibrate weight from self-reported measures at
the 18-month and the 10-year follow-up. Due to implausible differences between self-reported
and measured height, however, possibly caused by confusion about metric and imperial
measures by some participants, we used the clinically measured baseline height for the 18month follow-up. For the self-reported measure at the 10y follow-up, the calibrated value was
used, except when the difference between self-reported and latest objectively measured
height was larger than 3cm; these observations were replaced with the latest available clinical
measure without calibration.
weightc= -0.209 + 1.036 * weightsr -0.002 * (weightsr)2 , rmse = 2.59 kg
heightc= 7.387+ 0.926* heightsr + 0.0002 * (heightsr)2 , rmse = 1.02 cm
(Abbreviations: subscript c- clinical measure; subscript sr- self-reported; rmse- root mean
square error)
In addition, we conducted individual calibration (where applicable) of self-reported weight and
height using the following non-quadratic equations and there were no observable differences
from the quadratic regression estimates:
weightc= weightsr +offset, with mean (SD) for offset of 1.19 (2.59) kg
heightc= heightsr +offset, with mean (SD) for offset of -1.56 (2.98) cm
Supplementary table 1 Baseline characteristics of the participants by physical activity category;
the EPIC-Norfolk study
Men
Women
Inactive
Moderately inactive
Moderately active
Active
N
Age (years)
Body weight (kg)
Body mass index (kg/m2)
Daily energy intake (kJ)
3586
62.24 (9.06)
81.39 (12.17)
26.98 (3.54)
8864.06 (2772.92)
2858
59.05 (9.46)
80.63 (11.46)
26.47 (3.25)
9008.12 (2605.11)
2660
57.64 (8.87)
79.61 (11.11)
26.24 (3.18)
9299.95(2755.34)
Alcohol intake (g/week)
Cigarette smoking
11.29 (15.83)
13.29 (16.77)
11.61 (14.84)
2502
56.37 (8.64)
79.45 (10.88)
26.23 (3.13)
9835.84
(3766.40)
13.11 (17.05)
current
former
never
Social class
professional
manager
skilled non-manual
skilled manual
semi-skilled
unskilled
Educational level
none/less than O level
O level
A level
Degree
Self-reported stroke
Self-reported MI
Self-reported CA
Self-reported DM
499 (14.04)
2063 (58.06)
991 (27.89)
299 (10.54)
1523 (53.66)
1016 (35.80)
314 (11.87)
1413 (53.42)
918 (34.71)
293 (11.77)
1285 (51.63)
911 (36.60)
245 (6.99)
1348 (38.45)
552 (15.74)
810 (23.10)
445 (12.69)
100 (2.85)
322 (11.39)
1292 (45.72)
411 (14.54 )
483 (17.09)
259 (9.16)
43 (1.52)
184 (7.00)
950 (36.14)
258 (9.81)
740 (28.15)
394 (14.99)
97 (3.69)
124 (5.02)
767 (31.03)
204 ( 8.25)
851 (34.43 )
424 (17.15)
97 (3.92 )
1298 (36.29)
337 (9.42)
1475 (41.24)
467 (13.06)
99 (2.76)
283 (7.91)
163 (4.55)
172 (4.80)
746 (26.10)
267 (9.34)
1253 (43.84)
592 (20.71)
54 (1.89)
142 (4.97)
112 (3.92)
81 (2.84)
743 (27.93)
216 (8.12)
1286 (48.35)
415 (15.60)
40 (1.50)
107 (4.02)
97 (3.65)
66 (2.48)
747 (29.86)
186 (7.43)
1263 (50.48)
306 (20.23)
13 (0.52)
82 (3.28 )
69 (2.76)
44 (1.76)
N
Age (years)
Body weight (kg)
Body mass index (kg/m2)
Daily energy intake (kJ)
4277
62.28 (9.21)
69.34 (12.38)
27.03 (4.73)
7990.78 (2614.99)
Alcohol intake (g/week)
Cigarette smoking
current
former
never
Social class
professional
manager
skilled non-manual
skilled manual
semi-skilled
unskilled
Educational level
none/less than O level
O level
A level
Degree
Self-reported stroke
Self-reported MI
Self-reported CA
Self-reported DM
4.70 (7.95)
4493
58.05 (9.15)
67.78 (11.61)
26.14 (4.25)
8088.58
(2405.94)
5.81 (8.65)
3117
59.02 (8.52)
67.03 (11.33)
25.74 (4.13)
8131.31
(2433.94)
5.90 (8.54)
2147
54.96 (8.19)
66.86 (10.76)
25.54 (3.82)
8427.291
(2645.84)
6.10 (8.58)
1023 (13.18)
3505 (45.14)
3236 (41.68)
786 (10.78)
2908 (39.88)
3597 (49.33)
676 (11.78)
2351 (40.96)
2713 (47.26)
499 (10.79)
2908 (43.20)
2127 (46.01)
419 (5.51)
2604 (34.23)
1524 (20.03)
1687 (22.17)
1040 (13.67)
306 (4.02)
637 (8.77)
2926 (40.30)
1332 (18.35)
1377 ( 18.97)
799 (11.01)
160 (2.20 )
435 (7.63)
2110 (37.03)
763 (13.39)
1376 (24.15)
778 (13.65)
223 (3.91)
263 (5.74)
1518 (33.12)
520 (11.34 )
1331 (29.04 )
744 (16.23 )
186 (4.28)
2171 (50.87)
453 (10.61)
1366 (32.01)
278 (6.51)
74 (1.73)
113 (2.64)
351 (8.21)
113 (2.64)
1768 (39.35)
551 (12.26)
1636 (36.41)
538 (11.97)
38 (0.85)
65 (1.45)
290 (6.46)
65 (1.45)
1161 (37.26)
378 (12.13)
1129 (36.23)
448 (14.38)
12 (0.67)
22 (0.80)
205 (6.58)
25 (0.80)
820 (38.21)
234 (10.90)
847 (39.47)
245 (11.42)
21 (0.56)
17 (0.79)
108 (5.04)
17 (0.79)
p-value1
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
0.004
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
MI-myocardial infarction; DM-diabetes mellitus type 2; CA-cancer; 1Test for trend and χ2-test were conducted.
Continuous variables are shown as mean (SD). Categorical variables are shown as n (%).
<0.001
<0.001
<0.001
<0.001
Supplementary table 2 Age-adjusted proportions of inactive people in the EPIC-Norfolk by BMIcategory
Men
BMI category
<20 kg/ m2
N (% within BMI
category) of inactive
people in the EPICNorfolk at baseline
80 (55.6)
Normal (20-25 kg/ m2)
1887 (50.8)
Overweight (25-30 kg/m2)
3495 (64.8)
Obese (>30 kg/m2)
982 (69.7)
Women
BMI category
N (% within BMI
category) in EPICNorfolk at baseline
<20 kg/ m2
260 (62.0)
Normal (20-25 kg/ m2)
3327 (57.4)
Overweight (25-30 kg/m2)
3508 (56.6)
Obese (>30 kg/m2)
1675 (62.3)
Age-adjusted
proportion1 of inactive
people,
% (95% CI)
57.9
(51.9-63.9)
55.2
(54.0-56.5)
58.2
(57.3-59.2)
61.9
(60.1-63.6)
Age-adjusted
proportion of inactive
people,
% (95% CI)
66.8
(63.7-70.0)
62.4
(61.5-63.4)
65.9
(65.0-66.9)
70.8
(69.4-72.2)
BMI- body mass index
1 Estimates were obtained from mixed model with random effects taking into account 3 assessments of
physical activity and BMI
Supplementary table 3 Predicted national prevalence of physical inactivity in 2009 and 2020
BMI category
Men
<20 kg/ m2
Normal
(20-25 kg/ m2)
Overweight
(25-30 kg/m2)
Obese
(>30 kg/m2)
Women
<20 kg/ m2
Normal
(20-25 kg/ m2)
Overweight
(25-30 kg/m2)
Obese
(>30 kg/m2)
1
Prevalence1 of inactivity
% (95% CI)
2009
2020
1.16
(1.15-1.17)
17.67
(17.49-17.84)
25.61
(25.35-25.87)
13.62
(13.50-13.74)
Total: 58.04
(57.73-58.36)
0.59
(0.58-0.60)
7.33
(7.25-7.40)
23.76
(23.52-24.00)
27.79
(27.56-28.02)
Total: 59.46
(59.13-59.80)
1.34
(1.33-1.35)
25.59
(25.37-25.81)
21.74
(21.56-21.94)
16.99
(16.85-17.13)
Total: 65.65
(65.33-65.97)
2.02
(2.01-2.04)
16.39
(16.24-16.52)
21.30
(21.12-21.47)
27.17
(26.95-27.39)
Total: 66.89
(66.56-67.21)
Monte Carlo simulations with 10000 observations and 1000 repetitions were used to calculate the
prevalence of physical inactivity in 2009 and 2020