Table 1 Inaccurate coding for principal diagnoses and external cause codes
Principal diagnosesExternal cause codes
No% of total (95% CI)No% of total (95% CI)
Correct129274.0 (71.8 to 76.0)123171.0 (68.8 to 73.1)
Correct to 4th character, 5th character incorrect553.1 (2.4 to 4.1)0
Correct to 3rd character, 4th character incorrect1528.7 (7.4 to 10.1)452.6 (1.9 to 3.5)
1st character correct, 2nd or 3rd character incorrect18610.6 (9.2 to 12.2)34019.6 (17.8 to 21.6)
1st character incorrect623.5 (2.7 to 4.5)1186.8 (5.7 to 8.1)
Total17471734