Heterogeneity in the uptake, attendance, and outcomes in a clinical trial of a total diet replacement weight loss programme

Table 4 Weight change across different groups of engagement with the TDR treatment

Attendance group	N	Adjusted mean weight change from baseline (kg) (95% confidence intervals)			Within group, p value compared with baseline			Between group, p value compared with control
Attendance group	N	3 months	6 months	1 year	3 months	6 months	1 year	3 months	6 months	1 year
Control (usual care)	138	− 3.47 (− 4.53, − 2.41)	− 4.62 (− 5.69, − 3.54)	− 3.21 (− 4.27, – 2.14)	< 0.001	< 0.001	< 0.001	–	–	–
Low engagers¹	17	− 7.22 (− 11.9, − 2.56)	− 5.76 (− 9.43, − 2.10)	− 5.73 (− 9.20, − 2.26)	0.005	0.006	0.004	0.177	0.727	0.271
Engaged with weight loss phase only²	11	− 11.01 (− 14.24, − 7.78)	− 12.22 (− 15.74, − 8.70)	− 6.34 (− 10.05, − 2.63)	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	0.266
Engaged in entire programme (per protocol)³	106	− 13.76 (− 14.82, − 12.69)	− 15.77 (− 14.82, − 12.70)	− 11.47 (− 12.58, − 10.37)	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001

¹Did not engage in TDR phase, food re-introduction phase, or weight maintenance phase (attended < 6 sessions out of the possible 8 sessions during weeks 1–8, < 2 out of the possible 4 sessions offered during weeks 9–12, and < 2 out of the possible 3 sessions offered during weeks 13–26)
²Engaged with weight loss phase (either attended ≥ 6 of the TDR sessions out of the possible 8 during weeks 1–8 or attended ≥ 6 of the TDR sessions and ≥ 2 of the food re-introduction sessions out of the possible 4 sessions offered during weeks 9–12)
³Engaged in entire programme defined as engaging in weight loss phase (as defined above) and engaging with weight maintenance phase defined as attending ≥ 2 of the possible 3 weight maintenance sessions offered during weeks 13–26

ISSN: 1741-7015