Table 1

Study designs and characteristics of participants in 29 randomised trials of CPAP

Study (first author/year)	Total, n	Mean age	Male (%)	Study duration (months)	Delta BMI control	Delta BMI CPAP	Delta weight control	Delta weight CPAP	AHI (events/h)	Design*	Placebo- controlled	CPAP compliance (hours)	Diet counselling†	Physical activity counselling†
Arias (2005)^w1	27	52.0	100.0	3	0.0006	−0.2891	0.0833	−0.8571	44	C	Yes	6	No	No
Barbe (2001)^w2	54	54.0	90.0	1.5	0.08	0.43	0.31	0.8	55.4	P	Yes	5	No	No
Barbe (2012)^w3	723	51.9	85.6	48	−0.45	−0.25	−1.47	−0.45	38.5	P	No	5	Yes	No
Craig (2012)^w4	346	57.8	80.0	6	−0.2	0.2	−0.5	0.6	13.5	P	No	3	No	No
Drager (2007)^w5	24	45.5	100.0	4	−0.09	−0.10	−0.35	−0.16	59	P	No	6	No	No
Drager (2011)^w6	36	43.0	100.0	3	0.1	0	0.19	0	56.5	P	No	5.2	No	No
Durán-Cantolla (2010)^w7	340	52.4	81.0	3	−0.2	−0.3	−1	0	43.5	P	Yes	4.5	No	No
Hoyos (2012)^w8	65	49.0	100.0	3	0.1565	0.1533	0.4696	0.59	39.9	P	Yes	3.6	Yes	No
Hui (2006)^w9	46	50.8	80.4	3	0.48	0.35	1.11	0.85	31.2	P	Yes	5.1	No	No
Ip (2004)^w10	27	42.7	100.0	1	−0.22	0.27	−0.58	0.54	46	P	No	4.2	No	No
Jenkinson (1999)^w11	101	49.0	100.0	1	0.0735	−0.232	0.135	−0.6	30.7	P	Yes	5.4	No	No
Kritikou (men) (2013)^w12‡	22	54.3	100.0	2	0.051	0.418	0.1	1.192	42.1	C	Yes	6.01	No	No
Kritikou (women) (2013)^w12‡	20	57.6	0.0	2	0.358	0.24	0.976	0.778	32.10	C	Yes	6.00	No	No
Lam (2007)^w13§	67	46.0	79.0	2.5	−0.22	−0.42	−0.3	−1.19	21.4	P	No	4.2	No	No
Lozano (2010)^w14	64	59.2	68.8	3	0.34	0.37	0.9	1.1	52.67	P	No	5.6	Yes	No
Mansfield (2004)^w15	40	57.3	94.5	3	0.1	0.3	0.4	0.83	28.2	P	No	5.6	Yes	Yes
Montserrat (2001)^w16	45	54.0	91.0	1.5	0.44	0.39	1.24	1.06	54	P	Yes	4.25	Yes	No
Pedrosa (2013)^w17	35	56.0	77.0	6	−0.061	0.21	−0.049	0.492	29	P	No	6.01	No	No
Pepperell (2002)^w18	118	50.5	100.0	4	−0.232	0.1215	−0.71	0.35	35	P	Yes	4.9	No	No
Quan (2013)^w19	812	52.5	64.6	6	−0.034	0.037	−0.107	0.136	40.5	P	Yes	4.8	No	No
Robinson (2006)^w20	35	54.0	91.2	1	−0.21	0.12	−0.8	0.7	28.1	C	Yes	5.2	No	No
Ryan (2005)^w21	18	59.0	88.8	1	−0.25	0.06	−1.1	0.1	43.6	P	No	6.2	No	No
Ryan (2011)^w22	44	61.7	79.5	1	0.0361	0.6619	0.1462	2.228	35.9	P	No	4.96	No	No
Sivam (2012)^w23	27	47.0	96.3	2	−0.338	0.313	−0.888	0.804	37.2	C	Yes	4.6	No	No
Weinstock (2012)^w24	50	54.0	42.0	2	−0.17	0.31	−0.63	0.51	44	C	Yes	4.8	Yes	No
West (2007)^w25	40	56.2	100.0	3	0.0006	−0.2891	0.0833	−0.8571	36.1	P	Yes	3.3	Yes	Yes

Values presented are mean or percent unless indicated.
*For crossover studies, we used only data prior to the crossover to avoid carryover bias.
†We did not exclude studies that reported diet and physical activity counselling only. We only excluded articles that have an active protocol of diet and/or physical activity and/or drug combined to CPAP therapy.
‡Kritikou and colleagues reported two data sets (independent analysis in men and women).
§Lam and colleagues compared three groups: conservative measurements, CPAP and oral appliance. Only the first two groups were used for this analysis.
AHI, Apnoea–Hypopnoea Index; BMI, body mass index; C, crossover study design; P, parallel study design.