Table 1. Characteristics of each comparison included in the analysis. Values represent rescaled effect sizes within each comparison.

Review	Comparison	Continuous or dichotomous	N	Median	Interquartile range	Minimum	Maximum
A. Interventions to change practice
Audit & Feedback [21]	Audit & Feedback alone	C	13	1.22	1.12 to 1.68	1.05	1.99
	Audit & Feedback alone	D	25	1.07	0.98 to 1.18	0.71	2.16
	Multifaceted including audit & feedback	D	34	1.10	1.03 to 1.36	0.78	18.3
Educational outreach visits [22]	Any intervention including educational outreach visits	C	18	1.22	1.12 to 1.41	1.00	7.17
	Any intervention including educational outreach visits	D	33	1.11	1.07 to 1.35	0.78	4.25
Continuing education meetings & workshops [23]	CME –professional outcomes	C	32	1.32	1.07 to 1.90	1.00	4.57
Combined rescaled data			155	1.16	1.05 to 1.49	0.64	8.17
B. Interventions for smoking cessation
Nicotine replacement therapy [24]	Any NRT vs placebo/no NRT	D	50	1.34	1.19 to 1.98	0.50	4.33
Counselling [26]	Counselling vs control	D	17	1.56	1.32 to 2.01	0.58	5.5
Physician advice [25]	Minimal intervention	D	17	1.58	1.03 to 2.28	0.95	4.56
Motivational interviewing [27]	Motivational interviewing	D	14	1.62	1.16 to 1.99	0.92	5.28
Combined rescaled data			98	1.47	1.14 to 2.08	0.47	5.62
C. Simulated data		D	10000	1.31	1.02 to 1.69	0.33	4.78