Areas of research and clinical approaches to the study of liver abscess

Table 1 Distribution of the number of documents published on liver abscess, by publication type and clinical research approach (2001-2015)

Year	Publication type					Document category (by clinical research approach)
	Article	Review	Letter	Others	Total1	Case reports	Clinical trial	Evaluation studies	Others	Total1
2001	68	13	9	-	90	60	-	-	-	60
2002	60	8	8	1	77	48	1	-	-	49
2003	70	12	12	-	94	63	2	2	1	68
2004	67	16	4	-	87	43	1	1	1	46
2005	62	3	7	-	72	49	1	-	-	50
2006	67	6	13	1	87	55	1	-	-	56
2007	76	6	16	-	98	73	-	1	-	74
2008	53	4	9	-	66	37	1	2	-	40
2009	71	7	12	-	90	59	3	-	-	62
2010	60	9	7	1	77	56	1	1	-	58
2011	79	5	15	-	99	74	-	3	1	78
2012	71	8	7	1	87	63	2	1	-	66
2013	80	9	17	-	106	67	1	-	-	68
2014	77	12	11	2	102	64	2	1	1	68
2015	39	3	4	-	46	31	-	-	1	32
Total	1000	121	151	6	1278	842	16	12	5	875

¹The difference between the two totals is due to the fact that not all documents have been assigned to a category based on their clinical research approach.