Table 6
Possible reasons for repeat testing
| Not aware that the test has already been performed |
| Poor understanding of half lives of tumour markers |
| Lack of appreciation of the value of repeated testing of autoantibodies |
| Overemphasis on surveillance |
| Inexperience or lack of knowledge about the appropriate use of tests |
| Failure to check previous results |
| Test ordering routines that are difficult to change |
| Fear of errors of omission and litigation |
| Patients actively ask for tests |
