Table II.

Feasibility and acceptability: descriptive statistics

Domain	Control group	SGR group
Feasibility
Read messages your received	n = 18	n = 19
Not at all	0 (0.0%)	2 (10.5%)
Read about a quarter of a message	1 (5.6%)	0 (0.0%)
Read about a half of a message	0 (0.0%)	2 (10.5%)
Read about a three quarters of a message	1 (5.6%)	1 (5.3%)
Read the whole message	16 (88.9%)	14 (73.7%)
How many support texts read	n = 16	n= 19
Did not read any of the support messages	0 (0.0%)	1 (5.3%)
Read some of the support messages	1 (6.3%)	1 (5.3%)
Read most of the support messages	0 (0.0%)	1 (5.3%)
Read all of the support texts	15 (93.8%)	16 (84.2%)
When read the support texts	n= 18	n = 19
Ignored support messages completely	0 (0.0%)	1 (5.3%)
Read support messages when I had time	4 (22.2%)	1 (5.3%)
Read support messages right away	14 (77.8%)	17 (89.5%)
Acceptability
Usefulness of the intervention in helping you to quit smoking	n = 19	n = 19
Not at all useful	2 (10.5%)	1 (5.3%)
Somewhat useful	4 (21.1%)	2 (10.5%)
Undecided	1 (5.3%)	6 (31.6%)
Very useful	10 (52.6%)	7 (41.2%)
Extremely useful	2 (10.5%)	2 (15.8%)
Would you recommend the intervention to a friend	n = 19	n = 18
Not at all	2 (10.5%)	2 (11.1%)
Somewhat	2 (10.5%)	2 (11.1%)
Undecided	0 (0.0%)	1 (5.6%)
Very much	9 (47.4%)	7 (38.9%)
Extremely	6 (31.6%)	6 (33.3%)
Fidelity: response to ‘alert’ text messages sent
Number alerts sent per participant		n = 17
Median (25, 75th percentile)		84.0 (56.0, 91.0)
Minimum, maximum		18, 147
Number responses to alerts per participant		n = 17
Median (25, 75th percentile)		58.0 (18.0, 77.0)
Minimum, Maximum		0, 100
Percent alerts with response per participant		n = 17
Median (25, 75th percentile)		65.4 (42.9, 83.5)
Minimum, maximum		0, 95.6