Data quality can be checked at the point of data entry through setting the minimum and maximum value range for each element manually or generating a range (defined by a minimum and maximum value). The min-max range can be generated automatically by the system. The auto-generated min-max range is suitable only for normally distributed data. DHIS2 will determine the arithmetic mean and standard deviation of all values for a given data element /category option / organisation unit combination. Then the system will calculate the min-max range based on the
For data which is highly-skewed or zero inflated (as is often the case with aggregate data), the values which DHIS2 may not provide an accurate min-max range, which may then result in excessive false violations. Also note that currently, min-max values are calculated across all attribute combo options for a given data element /category option / organisation unit combination. In summary, the automatic generation of min/max values can be useful for many situations, but it would be advised to ensure that the data is actually normally distributed prior to using this function.
If you are using the default entry screen click on the element for which you want to set the min-max value. A pop-up window will appear in which you can enter the values. On subsequent data entry, if the values entered do not fall within the min-max range, the data entry cell will appear with an orange background, to highlight that this value does not fall within the min-max range. The min-max limits can be set in the following dialog.
In the same screen , users can comment on the reason for the discrepancy, such as an event at a facility which may have generated a large number of clients. Users may also flag the value for follow up (by pressing the star).
It is possible to generate and remove the min-max ranges by dataset using the "Min-max generation" function available in the data administration module. Just select a dataset and then an organisation unit from the dialog, as shown below.
Pressing "Generate" will create new min/max ranges for all data elements in the selected data sets for all orgunits (including descendants) of the selected organisation units.
Pressing "Remove" will permanently delete all min/max ranges for the selected datasetsa and organisation units.