I have analyzed the NNMi database, and found the below

The Key incidents are defined by the Incident Nature which can be found on the NNMi table NNM_INCIDENTS and the Incident name is stored under column “Name” and the correlation nature is stored under column “NATURE”

So after more analysis I found the below  table for mapping the value in nature column and map it to the correlation nature names used in the Incident Management views

so for Key correlation ( Root Cause, Service Impact, Stream Correlation,None, Info and  Rate Stream Correlation)

Value  Name

0    Root Cause
1    Secondary Root Cause
2    Symptom
3    Service Impact
4    Stream Correlation
5    None
6    Info
7    Dedup Stream Correlation
8    Rate Stream Correlation

I was able to get Incident Names them by the below Oracle SQL statement

   1: SELECT  "NNMI"."NMS_INCIDENTS"."NAME" as "NAME",COUNT(*)

   2:     FROM "NNMI"."NMS_INCIDENTS" 

   3:     WHERE ( ( "NATURE" = '0' ) OR ( "NATURE" BETWEEN '3' 

   4:     AND '6' ) OR ( "NATURE" = '8' ) ) group by Name

The result was the list below, but this may be expanded if you have more incidents from the system.

Note: This may be  the answer of your question

NnmHealthOverallStatus
SNMPAgentNotResponding
NodeDown
RateCorrelation
InterfaceDown
NodeOrConnectionDown
NonSNMPNodeUnresponsive
LicenseExpired
ConnectionDown
AggregatorLinkDegraded
LicenseNodeCountExceeded
AddressNotResponding
AggregatorDown

This was answer to question in HP Forum “NNMi List of Key Incidents”

http://h30501.www3.hp.com/t5/Network-Management-Support-Forum/NNMi-List-of-Key-Incidents/td-p/24529