be equally expressed by either partner in the relationship. intent: occurs out of anger or frustration rather than as a means of gaining control and power over the other partner. reciprocal and non-reciprocal the cdc divides domestic violence into two types: reciprocal, in which both partners are violent, and non-reciprocal violence, in which one partner is violent. of the four types, situational couple violence and mutual violent control are reciprocal, while intimate terrorism is non-reciprocal. violent resistance on its own is non-reciprocal, but is reciprocal when in response to intimate terrorism. by gender in the 1970s and 1980s, studies using large, nationally representative samples resulted in findings indicating that women were as violent as men in intimate relationships. this information diverged significantly from shelter, hospital, and police data, initiating a long-standing debate, termed "the gender symmetry debate". one side of this debate argues that mainly men perpetrate ipv (the gender asymmetry perspective), whereas the other side maintains that men and women perpetrate ipv at about equal rates (gender symmetry perspective). however, research on gender symmetry acknowledges asymmetrical aspects of ipv, which show that men use more violent and often deadly means of ipv. older conflict tactics scale (cts) methodology was criticized for excluding two important facets in gender violence: conflict-motivated aggression and control-motivated aggression. for example, women commonly engage in ipv as a form of self-defense or retaliation. research has shown that the nature of the abuse inflicted by women upon male partners is different from the abuse inflicted by men, in that it is generally not used as a form of control and does not cause the same levels of injury or fear of the abusive partner. scholars state these cases should not be generalized and each couple's specificities must be assessed. a 2016 meta-analysis indicated that the only risk factors for the perpetration of intimate partner violence that differ by gender are witnessing intimate partner violence as a child, alcohol use, male demand, and female withdrawal communication patterns. gender asymmetry while both women and men can be victims and perpetrators of ipv, the majority of such violence is inflicted upon women, who are also much more likely to suffer injuries as a result, in both heterosexual and same-sex relationships. although men and women commit equivalent rates of unreported minor violence via situational altercation, more severe perpetration and domestic battery tends to be committed by men. this is based on newer cts methodology as opposed to older versions that did not take into account the contexts in which violence takes place. a 2008 systematic review published in journal of violence and victims found that despite less serious altercation or violence being equal among both men and women, more serious and violent abuse was perpetrated by men. it was also found that women's use of physical violence was more likely motivated by self-defense or fear whereas men's use of violence was motivated by control. a 2010 systematic review published in the journal of trauma violence abuse found that the common motives for female on male ipv were anger, a need for attention, or as a response to their partner's violence. a 2011 review published in the journal of aggression and violent behavior found differences in the methods of abuse employed by men and women, suggesting that men were more likely to "beat up, choke or strangle" their partners, whereas women were more likely to "throw something at their partner, slap, kick, bite, punch, or hit with an object". researchers such as michael s kimmel have criticized cts methodology in assessing relations between gender and domestic violence. kimmel argued that the cts excluded two important facets in gender violence: conflict-motivated aggression and control motivated aggression. the first facet is a form of family conflict (such as an argument) while the latter is using violence as a tool for control. kimmel also argued that the cts failed to assess for the severity of the injury, sexual assaults and abuse from ex-partners or spouses. women generally suffer more severe and long-lasting forms of partner abuse than men, and men generally have more opportunities to leave an abusive partner than women do. researchers have found different outcomes in men and women in response to such abuse. a 2012 review from the journal psychology of violence found that women suffered from over-proportionate numbers of injuries, fear, and posttraumatic stress as a result of partner violence. the review also found that 70% of female victims felt frightened as a result of violence perpetrated by their partners whereas 85% of male victims expressed "no fear" in response to such violence. lastly, ipv correlated with relationship satisfaction for women but it did not do so for men. according to government statistics from the us department of justice, male perpetrators constituted 96% of federal prosecution on domestic violence. another report by the us department of justice on non-fatal domestic violence from 2003 to 2012 found that 76% of domestic violence was committed against women and 24% was committed against men. according to the united nations office on drugs and crime, the percentage of victims killed by their spouses or ex-spouses was 77.4% for women and 22.6% for men in 2008 in selected countries across europe. globally, men's perpetration of intimate partner violence against women often stems from conceptions of masculinity and patriarchy. studies done in the united states, nigeria, and guatemala all support the idea of men reacting violently towards their partners when their masculinity is threatened by changing gender roles. recent scholarship draws attention to the complexity of interactions between conceptions of masculinity and factors such as colonialism, racism, class and sexual orientation in shaping attitudes toward intimate partner violence around the world. gender symmetry