I think there is no direct function in Qlikview but we can achieve this
USL = Upper Specification Limit, LSL = Lower Specification Limit.
Food served at a restaurant should be between 38°C and 49°C when it is delivered to the customer. The process used to keep the food at the correct temperature has a process standard deviation of 2°C and the mean value for these temperature is 23. What is the process capability of the process?
USL (Upper Specification Limit) =49°C LSL (Lower Specification Limit) =39°C Standard Deviation =2°C Mean = 23
Process Capability & Process Capability Index
= Min((49 - 23) / (3 * 2), (23 - 39) / (3 * 2))
Hope this helps you.