You need to set up the parameters necessary for validating laboratory test question responses against normal ranges and CTC schemes. This information will be used by the study designer when creating laboratory test questions during Study Definition and when the results of these tests are validated during Data Entry.
Only users with the appropriate security rights will be able to set up the parameters for normal ranges and CTC.
Note that changes to normal ranges and CTC will only be reflected in the Study Definition module after the Library Management module has been closed.
Test results can vary between laboratories, due to differences in method and in the calibration of equipment. Normal ranges define the expected range of results for a particular test carried out at a particular laboratory. They can be linked to gender, age and effective date ranges.
Entered test results will be flagged with N (normal - within expected range), L (low - below expected range) or H (high - above expected range).
A question can be validated using normal ranges alone, or using both normal ranges and CTC.
The normal range is the set of values which are considered 'normal' test results. The normal range is mandatory and must be expressed by the study designer as two values. The data entry user will see a warning message when entering any value outside this range, if no feasible range has been defined.
The feasible range is the set of values which are considered to be 'not unlikely' test results. If a feasible range is specified by the study designer, the data entry user will see a warning message when entering any value outside this range (and inside the absolute range, if defined).
If no feasible range is specified, the Data Entry user will see a warning message when entering any value outside the normal range (and inside the absolute range, if defined).
The absolute range is the set of values outside of which no test result should ever occur. If an absolute range is specified by the study designer, the data entry user will see a Reject message when entering any value outside this range.
The feasible and absolute ranges are optional and may be expressed either with two values each or as percentages of the normal range. The units used for each range will be those defined for the test to which the range set applies.
When defining the feasible and/or absolute ranges as percentages of the normal range, bear in mind that the minimum and maximum work in different ways. See example
Common Toxicity Criteria (CTC) indicate the depth of abnormality of a laboratory test result. A CTC scheme is defined by a set of tables, each relating to a laboratory test. For each test there are four grades numbered from 1 to 4, with 1 being least abnormal and 4 being most abnormal. Unlike normal ranges, CTC cannot be linked to specific gender, age ranges or effective date periods.
Test results will be flagged with the grade number.
A question can be validated using both normal ranges and CTC. CTC alone can be used for validation providing the values are not based upon normal ranges. Results appear in a box to the right of the question. The normal range result is displayed on the left of this box and the CTC result to the right. For example, L2.