Study tracks unpredictability of intimate partner violence
Tragically, one of every three American women will experience intimate partner violence during her lifetime. Victims suffer not only physical injuries but are at increased risk of mental disorders.
This violence is often unpredictable, which may be its worst trait. Not knowing what will come next is sometimes a stronger predictor of a woman's health outcomes than violence frequency and severity, UT Health San Antonio research suggests.
"We expect severity and frequency to be the major driver to patient outcomes, but in some cases it isn't," said David Katerndahl, M.D., professor of family and community medicine in the university's Joe R. and Teresa Lozano Long School of Medicine. "The nonlinearity, or unpredictability, of the violence is much more of a driver."
In the team's most recent research article on the subject, Dr. Katerndahl and coauthors Sandra Burge, Ph.D.; Robert Ferrer, M.D., M.P.H.; Johanna Becho, M.S.; and Robert Wood, Dr.P.H., all of UT Health San Antonio, present a 10-item scale designed to reliably estimate violence unpredictability.
The Violence Nonlinearity Dynamics Scale may be a useful research tool in future studies of intimate partner violence, Dr. Katerndahl said. Researchers currently face the hurdle of obtaining sufficient valid data to measure nonlinearity, he said.
The team's latest study enrolled 143 women who recently experienced violence. The research was advertised as a family stress study at six San Antonio family medicine clinics, including two in the UT Health Physicians practice and four in the University Health System. Non-pregnant women ages 18-64 were screened in exam rooms while waiting for appointments. If husbands accompanied them, they were not screened.
Participants were assessed concerning the abusive behavior they faced and the violent environment around them. Other evaluations examined their level of hope and coping mechanisms. These assessments, paired with self-reports of the women over the eight-week study period, informed development of the Violence Nonlinearity Dynamics Scale.
Family therapist Johanna Becho interacted with the women on a weekly basis. "My role was to receive phone calls from each woman to track day-to-day events occurring in her life: the loss of a job, birth of a baby or loss of a child, and other things of that nature that can impact the dynamics of a relationship," Becho said.
"I also helped them to process their emotions after an incident occurred," she said. "It was very delicate dialogue, not something one shares with just anybody. It has to be with a trusted confidant, and that's what I became over the course of the eight weeks."
Enough freedom to decide
A certain amount of unpredictability was actually healthier for women than having their days uniform and tightly controlled. "Women who have what we call 'optimal nonlinearity,' which means they have some nonlinearity but it's not extreme, actually did better in the study in general," Dr. Katerndahl said.
"Some spontaneity allows us to mine for solutions," Becho said. "Whereas one woman might be open to counseling, another might be open to legal action, and another might be ready to start thinking about steps to exit the relationship. Leaving is a process."
Participant safety was the highest priority during the study. "We were able to set up safety measures that are not typical in everyday life, at least not in the life of a woman experiencing violence," Becho said. "For example, if a woman missed a phone call, we would place an outbound phone call to a safe number to try to reach her. Part of the study entry criteria was to provide a safe number for us to call if she couldn't reach us."
Enrollment also included a safety assessment.
"If a woman was in an extremely violent relationship, we just thought it was too risky for her to try to be in the study," Dr. Katerndahl said. "If there was a gun in the house, or he previously caused her to be hospitalized because of the violence, or another situation like that was occurring, we considered it to be too risky."
These women were referred to community resources such as the Bexar County Family Justice Center, the Battered Women's Shelter and local community counseling.
During calls with the women, Becho constantly looked for an indication that the violence had spiked to a level requiring action. These women were also referred to resources.
Of the 143 participants, analysis was conducted only of the 120 English-speaking women. These women included 94 Hispanics and 80 with at least a high school education. Sixty-two reported a household income of less than $20,000 annually.
The mean duration of their relationships was 13.8 years and the mean duration of violence was 9.7 years.
The study was published April 4 in the journal Primary Care Companion for CNS Disorders.
More information: David A. Katerndahl et al, Psychometrics of the Violence Nonlinear Dynamics Scale, The Primary Care Companion For CNS Disorders (2019). DOI: 10.4088/PCC.18m02404