Table 2

Frequency of within-institution duplicate imaging 12 months before and 12 months after introduction of PACS


Frequency of duplicate imaging


Before PACS
After PACS
P

Duplicate test within less than 7 days







     X-ray



          Chest
1146/60598 (1.9)
1070/60366 (1.8)
0.12
          Abdomen
339/8512(4.0)
273/8355 (3.3)
0.01
          Total
1485/69110 (2.2)
1343/68721 (2.0)
0.01




     Computed tomography



          Abdomen/Pelvis
275/14213 (1.9)
351/16060 (2.2)
0.13
          Head
1099/16523 (6.7)
1180/18102 (6.5)
0.62
          Chest
78/6627 (1.2)
120/8173 (1.5)
0.13
          Total
1452/37363 (3.9)
1651/42335 (3.9)
0.92




Duplicate test within less than 30 days







     X-ray



          Chest
3948/58212 (6.8)
3592/58204 (6.2)
<0.001
          Abdomen
667/8248 (8.1)
595/8123 (7.3)
0.07
          Total
4615/66460 (6.9)
4187/66327 (6.3)
<0.001




     Computed tomography



          Abdomen/Pelvis
596/13969 (4.3)
786/15764 (5.0)
0.003
          Head
1640/16364 (10.0)
1856/17868 (10.4)
0.26
          Chest
200/6525 (3.1)
309/8019 (3.9)
0.01
          Total
2436/36858 (6.6)
2951/41651 (7.1)
0.01




Duplicate test within less than 60 days







     X-ray



          Chest
6032/56841 (10.6)
5519/56902 (9.7)
<0.001
          Abdomen
857/8143 (10.5)
789/8012 (9.9)
0.16
          Total
6889/64984 (10.6)
6308/64914 (9.7)
<0.001




     Computed tomography



          Abdomen/Pelvis
968/13679 (7.1)
1174/15461 (7.6)
0.09
          Head
1883/16257 (11.6)
2157/17736 (12.2)
0.10
          Chest
341/6405 (5.3)
498/7857 (6.3)
0.01
          Total
3192/36341 (8.8)
3829/41054 (9.3)
0.01

Abbreviations: PACS, picture archiving communication systems.

All numbers reported as no. of index tests associated with a duplicate test/total no. of index tests (%).

All P values are for difference in frequency of duplicate imaging before versus after PACS.

You et al. BMC Health Services Research 2008 8:234   doi:10.1186/1472-6963-8-234