Uneven global distribution of randomized trials in hip fracture surgery

Figures & data

Figure 1. Summary of the literature search and inclusion/exclusion process.

Table 1. Summary of study characteristics of surgical hip fracture trials in our systematic review

Characteristic	No. of studies (% of studies)
No. of articles	199
Total sample size	29,119
Date of Publication
2010 to present	17 (9%)
2000–2009	89 (44%)
1990–1999	63 (32%)
1980–1989	27 (14%)
1970–1979	3 (2%)
Journal of publication
J Bone Joint Surg Br	37 (19%)
Acta Orthop	27 (14%)
Injury	22 (11%)
J Orthop Trauma	13 (7%)
Clin Orthop	11 (6%)
J Bone Joint Surg Am	10 (5%)
Arch Orthop Trauma Surg	10 (5%)
Int Orthop	9 (5%)
Ann Chir Gynaecol	5 (3%)
Other	55 (28%)
Type of fracture
Cervical	93 (47%)
Intertrochanteric	85 (43%)
Subtrochanteric	3 (2%)
Mixed	15 (8%)
Type of trial
Single-center	172 (86%)
Multicenter	24 (12%)
Type of Intervention
Comparison of implants	163 (82%)
Implant-modifying agent (cement, grafts)	16 (8%)
Implant placement-related technique (reaming, targeting)	9 (5%)
General surgical techniques	11 (6%)

Table 2. The number of randomized controlled trials and combined sample size on a national basis

Geographic region	No. of randomized controlled trials		Total study size
Oceania	3	1.5%	181	0.6%
Australia	2	1.0%	112	0.4%
New Zealand	1	0.5%	69	0.2%
Europe	156	78%	25,388	87%
Austria	1	0.5%	120	0.4%
Belgium	5	2.5%	462	1.6%
Denmark	8	4.0%	722	2.5%
Finland	4	2.0%	229	0.8%
France	3	1.5%	206	0.7%
Germany	10	5.0%	829	2.9%
Greece	4	2.0%	473	1.6%
Ireland	2	1.0%	222	0.8%
Italy	3	1.5%	266	0.9%
Netherlands	5	2.5%	1,157	4.0%
Norway	13	6.5%	3,022	10%
Spain	5	2.5%	879	3.0%
Sweden	50	25%	8,941	31%
Switzerland	3	1.5%	271	0.9%
United Kingdom	40	20%	7,589	26%
Asia	25	13%	2,367	8.1%
China	11	5.5%	1,247	4.3%
India	4	2.0%	381	1.3%
Iran	1	0.5%	80	0.3%
Israel	3	1.5%	365	1.3%
Nepal	1	0.5%	60	0.2%
South Korea	3	1.5%	138	0.5%
Taiwan	1	0.5%	66	0.2%
Turkey	1	0.5%	30	0.1%
North America	15	7.5%	1,183	4.1%
United States of America	11	5.5%	850	2.9%
Canada	4	2.0%	333	1.1%
Total	199		29,119

Figure 2. World map showing the cumulative sample sizes of randomized controlled trials on hip fracture, by city.

Table 3. Geographic distribution of multicenter trials

Country	No. of multicenter RCTs	Total sample size
Sweden	8	2,544
United Kingdom	6	1,161
The Netherlands	2	705
Norway	2	892
USA	2	175
Australia	1	60
Finland	1	426 ^a
India	1	102
Spain	1	183
Taiwan	1	66

^a This study was from a multinational study involving Sweden and Finland; the publication and sample size numbers for both countries were included.