Table 1.

Summary of studies included in the systematic review, including description of study design, number of studies, number of patients, source of funding and length of follow-up

	Study design
	RCT	Observational study	Case study
Number of included studies n (%)	99 (46.3)	87 (40.6)	28 (13.1)
Number of patient n (%)	28 232 (33.8)	55 250 (66.1)	53 (0.1)
Source of funding n (%)
None	5 (0.05)	7 (0.08)	5 (0.18)
Industry	54 (0.55)	41 (0.47)	0
Public	0	1 (0.01)	4 (0.14)
Unspecified	40 (0.40)	38 (0.44)	19 (0.68)
Length of follow-up in months
Mean (SD)	4.85 (5.34)	8.26 (11.58)	5.16 (4.28)
Range	0.2–36	0.5–60	0.5–19

RCT, randomised controlled trial.