You'll have to help me out a bit. That isn't the "largest study" to date, but more to the point, it was looking at age and ethnic differences in homicide. A quote from your cited article:
<<
Across all racial/ethnic groups of women, over half of female homicides for which circumstances were known were IPV-related, with >90% of these women being killed by their current or former intimate partner.>>
In other words, the study aimed to find out how many women were murdered in a context
that included known DV.
So of the total homicides of women, slightly more than half of the homicides were in a situation where DV was known to have occurred - and in almost half the cases, some form of violence was recorded in legal documents in the month before the homicide. Which is interesting. Since Suzanne's family seems to believe (see Gene Moorman's obituary) that DV was involved here, it makes me curious whether LE also knew this.
At any rate, you cited the figure for "known DV before homicide," not total homicides.
That's a screen shot of the chart from your cited article. Of ALL homicides (including ones where there was no known domestic violence in advance of the homicide), the stat they provide is 79% of the total homicides (see Table 2).
This study was large, but not "the largest." It looks at 18 states, not the entire US. I do believe the FBI has papers that look at the total number for all 50 states (and I think the percentage is lower than 79% but either figure is astonishingly high from my point of view).
The 50% figure is women who were in the process of experiencing domestic violence or had experienced it within a month before their deaths.
However, 29% of women were killed by an intimate partner without any prior or ongoing domestic violence. Think KB. Or Robert Spangler's first wife.
imgur.com
Link to the chart, since first link didn't work. Over 50% of women killed by intimate partners had experienced recent DV; of women killed, 90% had experienced DV recently, 79% of all women entered into the study (due to having a DC with homicide listed) were killed by an IP.