Table 1. Changes in the key publication metrics of dental journals from 2003 to 2012.

Metric		2003	2004	2005	2006	2007	2008	2009	2010	2011	2012	β	p-value	R2
Publication frequency	Annual	0	0	0	0	0	0	1	0	0	0	0.018	0.631	0.030
	Semiannual	0	0	0	0	0	0	0	3	3	3	0.382	0.006	0.636
	Quarterly	4	6	7	6	9	10	14	20	21	22	2.164	< 0.001	0.913
	Bimonthly	28	27	27	28	27	28	32	32	34	33	0.800	0.001	0.750
	Monthly	12	13	13	13	13	14	15	19	20	20	0.958	< 0.001	0.826
	Total No. of Journals	46	48	49	49	51	55	64	77	81	83	4.564	< 0.001	0.876
Indices	Total Cites	97081	107503	115087	123328	146199	167243	181025	201478	211097	233232	15616	< 0.001	0.985
	Median Impact Factor	1.05	1.156	1.288	1.252	1.592	1.442	1.369	1.345	1.204	1.238	0.015	0.397	0.091
	Aggregate Impact Factor	1.119	1.29	1.398	1.498	1.699	1.679	1.732	1.746	1.674	1.739	0.065	0.001	0.787
	Aggregate Immediacy Index	0.159	0.179	0.177	0.215	0.238	0.251	0.282	0.243	0.261	0.275	0.013	< 0.001	0.833
	Aggregate Cited Half-life	8.9	8.7	8.7	8.6	8.5	8.4	8.2	8.3	8.4	8.4	-0.060	0.002	0.726
	Aggregate Citing Half-life	9.0	9.0	9.0	8.8	8.8	8.7	8.5	8.6	8.8	8.9	-0.032	0.090	0.316
Number of references per publication	Articles	26.8	26.8	27.6	28.0	28.2	29.3	29.1	29.5	30.6	30.5	0.447	< 0.001	0.963
	Reviews	75.5	100.4	89.3	91.9	100.6	79.0	76.3	72.2	67.8	64.8	-2.899	0.031	0.459
	Other	4.1	3.8	2	2.7	2.2	2.8	2.7	2.6	2.7	3.6	-0.052	0.524	0.053