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Table 1 Cluster and participant characteristics per trial arm and overall, at baseline. Data are summarised as the median and inter-quartile range (IQR), unless otherwise stated

From: The effectiveness of the Structured Health Intervention For Truckers (SHIFT): a cluster randomised controlled trial (RCT)

  Control
Clusters = 13
Participants = 199
SHIFT
Clusters = 12
Participants = 183
Overall
Clusters = 25
Participants = 382
Missing values
Cluster level
Cluster size category, n (%)     0
 Small (< 40 drivers) 81 (40.7%) 93 (50.8%) 174 (45.6%)  
 Large (≥ 40 drivers) 118 (59.3%) 90 (49.2%) 208 (54.4%)  
Participant level
Cluster size     0
 Median (IQR) 14 (12, 17) 14 (13, 17) 14 (13, 17)  
 Min, max 9, 24 11, 25 9, 25  
Age, Mean (SD) 48.3 (9.7) 48.6 (9.1) 48.4 (9.4) 2
Sex, n (%) male 196 (98.5%) 182 (99.5%) 378 (99.0%) 0
Ethnicity, n (%)     1
 White British 154 (77.4%) 152 (83.1%) 306 (80.1%)  
 Other ethnicity 45 (22.6%) 30 (16.4%) 75 (19.6%)  
Shift patterna, n (%)     0
 Morning 146 (73.4%) 124 (67.8%) 270 (70.7%)  
 Afternoon 29 (14.6%) 31 (16.9%) 60 (15.7%)  
 Night 35 (17.6%) 45 (24.6%) 80 (20.9%)  
Duration working at company (years) 6.17 (3.67, 11.50) 9.30 (4.06, 14.27) 7.75 (3.88, 13.42) 0
Duration working as a HGV driver (years) 15.00 (6.00, 26.00) 17.00 (10.00, 25.02) 16.00 (9.00, 25.17) 0
Average hours worked per week 48 (45, 50) 48 (45, 50) 48 (45, 50) 0
IMD rank 16779 (8500, 22904) 16040 (7934, 22171) 16591 (8165, 22544) 30
Marital status, n (%)     0
 Married 133 (66.8%) 113 (61.8%) 246 (64.4%)  
 Living with partner 34 (17.1%) 31 (16.9%) 65 (17.0%)  
Other (separated/divorced, single, widowed) 32 (16.1%) 39 (21.4%) 71 (18.6%)  
Level of education, n (%), degree or above 16 (8.0%) 10 (5.5%) 26 (6.8%) 8
Diabetes history, n (%), yesb 15 (7.5%) 9 (4.9%) 24 (6.3%) 1
Smoking status, n (%)     1
 Never smoked 73 (36.7%) 77 (42.1%) 150 (39.3%)  
 Ex-smoker 84 (42.2%) 73 (39.9%) 157 (41.1%)  
 Current smoker 42 (21.1%) 32 (17.5%) 74 (19.4%)  
Anthropometric measures and markers of adiposity
 Weight (kg) 94.0 (84.2, 106.9) 95.7 (84.0, 106.4) 94.8 (84.1, 106.5) 2
 Body fat (%), mean (SD) 26.8 (5.8) 27.3 (6.0) 27.0 (5.9) 11
 Fat mass (kg) 25.3 (19.6, 32.3) 25.6 (19.9, 32.7) 25.5 (19.6, 32.4) 11
 Fat Free mass (kg), mean (SD) 69.3 (8.6) 69.6 (7.8) 69.5 (8.2) 12
 Body mass index (kg/m2) 29.6 (27.0, 32.8) 29.9 (26.9, 33.7) 29.8 (26.9, 33.2) 2
 Waist circumference (cm) 104.4 (94.6, 113.1) 103.0 (95.0, 113.5) 103.7 (95.0, 113.4) 2
 Hip circumference (cm) 106.5 (101.0, 111.8) 107.5 (103.0, 114.0) 107.0 (102.0, 112.5) 2
 Waist-hip ratio (cm), mean (SD) 0.97 (0.07) 0.97 (0.07) 0.97 (0.07) 2
 Neck circumference (cm) 40.2 (38.9, 42.5) 41.0 (38.3, 42.5) 40.5 (38.4, 42.5) 2
Resting blood pressure (BP) and heart rate
 Systolic BP (mmHg) 130 (122, 140) 130 (122, 138) 130 (122, 139) 2
 Diastolic BP (mmHg) 82 (76, 90) 81 (76, 88) 82 (76, 88) 2
 Heart rate (bpm), mean (SD) 68 (10) 68 (10) 68 (10) 4
Biochemical assessments
 Glycated haemoglobin (mmol/mol) 35 (32, 38) 34 (31, 38) 35 (31, 38) 14
 Glycated haemoglobin (%) 5.4 (5.1, 5.6) 5.3 (5.0, 5.6) 5.4 (5.0, 5.6) 14
 Triglycerides (mmol/l) 1.3 (1.0, 2.1) 1.3 (0.9, 2.1) 1.3 (0.9, 2.1) 5
 HDL cholesterol (mmol/l) 1.1 (1.0, 1.4) 1.1 (1.0, 1.4) 1.1 (1.0, 1.4) 5
 LDL cholesterol (mmol/l) 2.8 (2.3, 3.5) 2.8 (2.4, 3.5) 2.8 (2.3, 3.5) 6
 Total cholesterol (mmol/l) 4.4 (3.8, 5.1) 4.4 (3.8, 5.1) 4.4 (3.8, 5.1) 5
Physical activity and sitting time 41
 Steps/day 8471 (6774, 10160) 8725 (7033, 11298) 8583 (6922, 10696)  
 Sitting (mins/day), mean (SD) 678 (91) 651 (97) 665 (95)  
 Standing (mins/day) 195 (165, 238) 213 (180, 244) 203 (169, 243)  
 Stepping (mins/day) 112 (90, 134) 116 (93, 149) 114 (92, 139)  
 MVPA (mins/day) 10 (6, 18) 11 (6, 21) 10 (6, 19)  
 LPA (mins/day) 97 (81, 114) 102 (83, 129) 99 (82, 123)  
 Number of valid days 8 (6, 8) 7 (5, 8) 7 (6, 8)  
 Waking wear time (mins/day) 993 (955, 1033) 989 (950, 1022) 990 (953, 1032)  
Sleep 36
 Sleep window duration (mins/day) 426 (393, 465) 424 (387, 459) 425 (390, 460)  
 Sleep duration (mins/day) 371 (336, 405) 371 (340, 407) 371 (337, 406)  
 Sleep efficiency (%) 88.5 (84.2, 91.3) 88.9 (84.6, 92.0) 88.6 (84.3, 91.5)  
 Number of valid nights 6 (6, 6) 6 (5, 6) 6 (6, 6)  
Fruit and vegetable intake and dietary quality 111
 Fruit intake (grams/day), mean (SD) 101 (122) 135 (158) 117 (141)  
 Vegetable intake (grams/day), Mean (SD) 110 (135) 128 (166) 118 (150)  
 Dietary quality score, mean (SD) 11.1 (2.0) 11.1 (2.1) 11.1 (2.0)  
  1. aApproximately 90% of the sample were shift workers, where working hours did not fit entirely within the conventional 8 am–6 pm window. The categories applied (morning, afternoon, night) refer to the predominant period of the day (or night) that participants spend working
  2. bIn the control group, 14 of the 15 have type 2 diabetes; 1 did not report type. Eleven of the 15 controlled their diabetes with medical treatment, 3 with lifestyle only and 1 did not report control type. In the SHIFT group, all 9 had type 2 diabetes, 7 controlled their diabetes with medical treatment, 2 with diet only