Stets and Straus - 825 respondents:
49% reported reciprocal violence

28% reported that only the wife was violent

23% reported that only the husband was violent.

The men reported:

men struck the first blow 43.7% of the time...they reported women hitting first 44.1% of the time

The women reported:

women striking first 52.7% of the time...men hitting first 42.6% of the time.

Women are more likely to hit back (24.4% vs. 15%)

Stets and Straus (1992) combined the 1985 US National Family Violence Resurvey (N = 5,005) with a sample of 526 dating couples to generate a large and representative sample of male-female relationships, in which they reported incidence of intimate violence by gender. Using a subset of 825 respondents who reported experiencing at least one or more assaults the authors found that in ½ (49%) of the incidents the couples reported reciprocal violence, in 1/4 (23%) of the cases the couples reported that the husband alone was violent and 1/4 (28%) reported the wife alone was violent. Men (n = 297) reported striking the first blow in 43.7% of cases and that their partner struck the first blow in 44.1% of the cases. The women (n = 428) reported striking the first blow in 52.7% of the cases and that their partner struck first in 42.6% of the cases. Stets and Straus (1992) concluded that not only do women engage in a comparable amount of violence, they are “at least as likely” to instigate violence. The results also indicated that women were more likely to hit back (24.4%) than men (15%) in response to violent provocation by a partner (Straus & Gelles, 1992). This latter result is difficult to explain from the patriarchal view that women are more afraid of male violence than the reverse. Stets and Straus also analyzed for level of violence x gender. They concluded that equal levels of violence by both men and women were the most common form of violence (40% of married couples). The second most frequent form was women using severe violence against men who were either completely non-violent or who used only minor violence (about 16 % of married couples). The stereotypical pattern (male severe, female none or minor) was found for only 8% of married couples. (emphasis mine) (Donald G. Dutton)