Increase precision: MedCalc usually reports numbers rounded to 4 decimal places. With this option you increase or decrease the number of decimals in the statistical reports. Note that this may result in spurious 'accuracy'.
By entering a negative number, you can decrease the number of decimals.
The number of decimals you enter here is the increment of the default number of decimals used by MedCalc; it is not the number of decimals used in the report. If you enter 1 here, the number of decimals in the reports will be increased from 4 to 5 (or 3 to 4 where applicable).