doxygen enum showing twice in index when in group

Question

There is a header file that contains a typedef enum. I cannot modify this header. The enum is used within my project and I need to document the enum. I do this by adding a @enum doxygen command to a .dox file thus:

/** @addtogroup constants
  @{
  @enum INT_VALS
    Description of INT_VALS enum
  @var FIRST_VAL
    Description of first value
  @var SECOND_VAL
    Description of second value
  @}
*/

This creates an entry in the modules section of the documentation for INT_VALS with each enum value listed as a sub-entry. Each enum value is also listed in the module as a separate entry. The enum table is created correctly in the documentation.

I want to have just the INT_VALS entry and its child entries in the modules index, not the extra individual duplicate entries.

Output is html.