Table 2.

Summary of the meta-analysis of the treatment effect between groups based on increments between baseline and end trial data (see Additional file 1 for further details)

Index # online supportive	ID# Selected studies	‘Random/Fixed’ effect model	Study duration	Difference in means between groups (in mm)	95 % confidence interval	p-value	Test for heterogeneity*
Appendix	See Appendix S3					Test for overall effect	p-value	I2
Mean PD
App. S38	IX, VIII, XIII	Fixed	Short term (2–3 months)	−0.49	(−0.6; −0.33)	<0.00001	0.31	14 %
	VI, XI, XVI, XVII		Medium term (6 months)	−0.41	(−0.57; −0.24)	<0.00001	0.49	0 %
	I, II, III		Long term (12 months)	−0.54	(−0.75; −0.34)	<0.00001	0.41	0 %
	All	Random	2–12 months	−0.47	(−0.58; −0.37)	<0.00001	0.57	0 %
PD > 4 mm
App. S39	IV, V, X, XII, XIV	Random	3–24 months	−0.55	(−0.79; −0.30)	<0.0001	0.19	34 %
PD 4-6 mm
App. S40	I, II, III, XVII, XIX	Random	6–12 months	−0.55	(−0.73; −0.37)	<0.00001	0.04	59 %
PD ≥ 6 mm
App. S41	I, II, III, VI, VII, XII, XVII, XIX	Random	6–12 months	−0.86	(−1.07; −0.65)	<0.00001	0.51	0 %
Mean CAL
App. S42	I, II, III, VI, VIII, IX, XI, XIII, XVI, XVII, XX	Random	3–24 months	+0.33	(0.23; 0.43)	<0.00001	0.83	0 %
CAL > 4 mm
App. S43	IV, V, X, XII, XIV	Random	2–24 months	+0.35	(0.07; 0.63)	0.02	0.004	74 %
CAL 4-6 mm
App. S44	I, II, III, XVII, XIX	Random	6–12 months	+0.42	(0.24; 0.61)	<0.00001	0.07	54 %
CAL ≥ 6 mm
App. S45	I, II, III, VI, VII, XII, XVII, XVIII, XIX	Random	6–24 months	+0.75	(0.40; 1.09)	<0.0001	<0.0001	79 %

* = A chi-square test resulting in a p < 0.1 was considered an indication of significant statistical heterogeneity. As a rough guide for assessing the possible magnitude of inconsistency across studies, I2 statistic of 0–40 % was interpreted as not be important, and above 40 % moderate to considerable heterogeneity may be present