Table 1.

Frequencies of studies grouped according to the period, journal and region of origin

Study type		Clinical trial	Accuracy study	Case-control study	Cross-sectional study	Case-series	Narrative review
		n (%)	n (%)	n (%)	n (%)	n (%)	n (%)
Period	2000-2004	1 (2.9%)	1 (2.0%)	0	1 (2.0%)	28 (57.1%)	3 (6.1%)
	2005-2009	1 (2.9%)	1 (2.9%)	1 (2.9%)	0	13 (38.2%)	1 (2.9%)
Journal	AOB	2 (9.5%)	1 (4.8%)	0	0	12 (57.1%)	2 (9.5%)
	RBO	0	1 (1.6%)	1 (1.6%)	1 (1.6%)	29 (46.8%)	2 (3.2%)
Region of origin	North-Northeast-Midwest	0	0	0	0	4 (57.1%)	0
	International	0	0	0	0	0	0
	Southeast	2 (3.4%)	2 (3.4%)	1 (1.7%)	1 (1.7%)	28 (47.5%)	4 (6.8%)
	South	0	0	0	0	9 (60.0%)	0

AOB = Acta Ortopédica Brasileira; RBO = Revista Brasileira de Ortopedia.