PREVIEW study—influence of a behavior modification intervention (PREMIT) in over 2300 people with pre-diabetes: intention, self-efficacy and outcome expectancies during the early phase of a lifestyle intervention

Figures & data

Figure 1 Intervention and data collection structure.

Abbreviations: PREVIEW, prevention of diabetes through lifestyle intervention and population studies in Europe and around the world; PREMIT, the preview behavior modification intervention toolbox; RCT, randomized controlled trial; CID, clinical investigation day.

Table 1 Participant characteristics at the start of the trial

Characteristic	All participants	Achievers	Non-achievers	P-value
Age (mean ± SD)	52.13 ± 11.36	52.32 ± 11.21	49.92 ± 12.69	<0.05
Female	1352 (66.9%)	1234 (66.5%)	118 (72.4%)	>0.05
Male	668 (33.1%)	623 (33.5%)	45 (27.6%)
Married or in civil partnership	1389 (68.8%)	1288 (69.3%)	101 (62%)	>0.05
Living in a household with at least 2 adults	1584 (78.2%)	1465 (78.9%)	119 (72.9%)	>0.05
Living in a household with at least 1 child	450 (22.3%)	403 (21.7.8%)	47 (28.8%)	<0.05
Ethnicity—Caucasian	1790 (88.6%)	1658 (89.3%)	132 (81%)	<0.05
Ethnicity—other	230 (11.4%)	199 (10.7%)	31 (19%)
In paid employment (full- or part-time)	1225 (60.6%)	1138 (61.3%)	87 (53.4%)	>0.05

Table 2 Number of “achievers” and “non-achievers” recorded as attending the group counseling sessions

Group counseling session	Achievers n = 1857 (%)	Non-achievers n = 163 (%)
1st group counseling (CID1), week 0, start of LCD	1857 (100)	163 (100)
2nd group counseling, week 2	1619 (87.2)	128 (78.5)
3rd group counseling, week 4	1582 (85.2)	123 (75.5)
4th group counseling, week 6	1530 (82.4)	118 (72.4)
5th group counseling (CID2), week 8, end of LCD	1529 (82.3)	53 (32.5)

Abbreviation: CID, clinical investigation day; LCD, low-calorie diet.

Table 3 Mean, standard deviation, and number of participants for behavior modification outcomes

Time point Outcome measure (mean ± SD)	CID1			CID2
	All (n = 1973)	Achievers (n = 1813)	Non-achievers (n = 160)	All (n = 1973)	Achievers (n = 1813)	Non-achievers (n = 160)
Self-efficacy healthy diet (Scale 1–4)	3.13 ± 0.57	3.14 ± 0.57	3.10 ± 0.61	3.23 ± 0.56	3.24 ± 0.56	3.12 ± 0.52
Self-efficacy physical activity (scale 1–4)	2.83 ± 0.64	2.83 ± 0.64	2.80 ± 0.72	2.85 ± 0.67	2.88 ± 0.66	2.61 ± 0.67
Outcome expectancies benefits healthy diet (Scale 1–4)	3.34 ± 0.47	3.34 ± 0.46	3.37 ± 0.47	3.44 ± 0.46	3.45 ± 0.45	3.27 ± 0.51
Outcome expectancies disadvantages healthy diet (Scale 1–4)	2.00 ± 0.53	1.98 ± 0.53	2.18 ± 0.53	1.96 ± 0.52	1.95 ± 0.52	2.16 ± 0.48
Outcome expectancies benefits regular exercise (Scale 1–4)	3.23 ± 0.47	3.22 ± 0.47	3.31 ± 0.49	3.29 ± 0.47	3.30 ± 0.47	3.18 ± 0.48
Outcome expectancies disadvantages regular exercise (Scale 1–4)	2.27 ± 0.63	2.25 ± 0.62	2.44 ± 0.64	2.18 ± 0.63	2.17 ± 0.62	2.35 ± 0.64
Intention to eat healthy (Scale 1–7)	6.46 ± 1.05	6.46 ± 1.06	6.43 ± 0.94	6.70 ± 0.70	6.72 ± 0.70	6.49 ± 0.66
Intention to exercise regularly (Scale 1–7)	5.79 ± 1.56	5.78 ± 1.56	5.92 ± 1.51	6.41 ± 1.04	6.46 ± 1.01	5.92 ± 1.22
Intention to lose weight (Scale 1–7)	6.58 ± 1.07	6.57 ± 1.09	6.68 ± 0.89	6.12 ± 1.49	6.10 ± 1.52	6.23 ± 1.04
Coping self-efficacy nutrition (Scale 1–4)	n/a	n/a	n/a	3.28 ± 0.67	3.29 ± 0.67	3.18 ± 0.64
Coping self-efficacy physical activity (Scale 1–4)	n/a	n/a	n/a	2.89 ± 0.70	2.90 ± 0.70	2.72 ± 0.70

Notes: For self-efficacy and coping self-efficacy (diet and physical activity), higher scale value indicates higher self-efficacy. For intention (weight loss, nutrition, physical activity), higher scale value indicates higher intention. For outcome expectancies (benefits and disadvantages), higher scale value indicates higher expectations of benefits or disadvantages.

Abbreviations: CID, clinical investigation day; n/a, not applicable.