Pre-notification and reminder SMS text messages with behaviourally informed invitation letters to improve uptake of NHS Health Checks: a factorial randomised controlled trial

Table 3 Odds ratios comparing uptake in intervention and control conditions

Pre-notification	Letter	Reminder	Total patients	Uptake (n)	Uptake proportion	Odds ratio	95% Confidence Interval.
No	control	no	814	148	0.18	1.00
No	open-ended	no	724	167	0.23	1.35	1.05	1.73
No	time-limited	no	747	158	0.21	1.21	0.94	1.55
No	social norms	no	800	159	0.20	1.12	0.87	1.43
No	control	yes	885	210	0.24	1.40	1.11	1.77
No	open-ended	yes	692	194	0.28	1.75	1.37	2.24
No	time-limited	yes	754	203	0.27	1.66	1.30	2.11
No	social norms	yes	723	176	0.24	1.45	1.13	1.85
Yes	control	no	783	168	0.21	1.23	0.96	1.57
Yes	open-ended	no	765	204	0.27	1.64	1.29	2.08
Yes	time-limited	no	761	197	0.26	1.57	1.24	2.00
Yes	social norms	no	754	179	0.24	1.40	1.10	1.79
Yes	control	yes	803	192	0.24	1.41	1.11	1.80
Yes	open-ended	yes	727	179	0.25	1.47	1.15	1.88
Yes	time-limited	yes	734	220	0.30	1.93	1.52	2.44
Yes	social norms	yes	778	190	0.24	1.45	1.14	1.85

ISSN: 1471-2458