Program Goals/Target Population
The Period of PURPLE Crying program materials are designed to provide new parents with knowledge and behavioral strategies to prevent shaken baby syndrome. The program materials address the association between infants’ inconsolable crying and shaken baby syndrome. Prolonged bouts of inconsolable crying clustered in the evening for the first few months after birth, which persist despite all efforts to soothe the infant, are a natural source of frustration and even anger for parents. Even parents who understand the harmful effects of shaking a baby may feel the urge to shake the infant if they do not already have alternative strategies in place. The program aims to educate expectant or very new parents to expect this typical phase of their new infant’s life and provides them with educational materials on the dangers of shaking, strategies for avoiding shaking their infants, and the importance of sharing this knowledge with other caregivers. The overall goal is to prevent parents from shaking their crying babies in frustration.
Because shaken baby syndrome can occur by 2 weeks of age, the program aims to provide information to parents before or soon after birth. Materials include an 11-page booklet and a DVD about infant safety. The materials describe the PURPLE period during which a healthy infant’s crying could frustrate caregivers: Peak of crying, during which crying increases after 2 weeks, increases and peaks in the second month, and then declines; Unexpected timing of prolonged crying bouts; Resistant to soothing; Pain-like face; Long-lasting bouts of crying; and Evening, which refers to late afternoon and evening clustering.
The materials are meant to reinforce that inconsolable crying is normal infant behavior, suggest ways to soothe infants, emphasize that soothing will not always work, describe why inconsolable crying is frustrating to parents and other caregivers, and suggest three guidelines to use while caring for a crying infant. First, the materials encourage parents to use typical calming responses (such as carry, comfort, walk, and talk) with their infants. If the crying is too frustrating, they are next encouraged to put the baby down in a safe place, walk away, calm themselves down, and then return to check on the baby. Finally, it is stressed that they must never shake a baby. The parents are also encouraged to share this information with all their infant’s other caregivers.
Period of PURPLE Crying is based on the idea that parents and other caregivers will not shake a baby if they understand the dangers of shaking an infant and know of alternative strategies. The program provides parents with the knowledge that there may be a period of several months, beginning around 2 weeks of age, during which it is normal for infants to have prolonged, inconsolable, and unpredictable episodes of crying that cluster in the evening, but that after a few months, these periods will lessen or come to an end. However, because this period is very frustrating for parents and other caregivers, they are taught about how shaking a baby can inflict traumatic brain injury, with or without contact between the child’s head and a hard surface, and with serious health consequences for the child, including head trauma and death. Thus, it is important, even among parents and caregivers with this knowledge, to provide them with strategies that they can use when faced with the frustration of prolonged infant crying.
Barr and colleagues (2009) conducted a randomized controlled trial to evaluate the Period of PURPLE Crying on new mothers’ knowledge and behaviors surrounding shaken baby syndrome. Research assistants or discharge nurses recruited participants from hospitals in the Greater Vancouver area (British Columbia, Canada), between May 2005 and November 2006. A total of 37 percent of the treatment group and 38 percent of the comparison group were from Vancouver, 29 percent of both groups were from Fraser South, 27 percent of both groups were from Fraser North, and 6 percent of both groups were from North Shore.
Eligible mothers had an uneventful pregnancy, a healthy singleton infant (defined as greater than 37 weeks’ gestation), access to a DVD player, and were fluent in English. After obtaining verbal consent over telephone or in person, participants were randomly assigned to receive the treatment or were assigned to the comparison group. Period of PURPLE Crying materials included an 11-page booklet and a DVD, and materials for the control group included injury prevention materials consisting of two brochures and a DVD about infant safety. These materials were delivered to new mothers during routine visits with a public health nurse within 2 weeks after their discharge from the hospital. Both groups received a Baby’s Day Diary with instructions, a sealed envelope with the study materials, and a teddy bear. Nurses, who were blinded to which mothers were in the treatment or comparison group, demonstrated how to use the diary during the visit.
Five weeks after giving birth, the participating mothers received telephone calls 1 day before and 1 day after starting to use the diary to help them with completing it. Three weeks later (i.e., 8 weeks after giving birth), an independent research group, blinded to study hypotheses, materials, and treatment or comparison group status, telephoned the mothers to administer a questionnaire that took approximately 20 minutes.
A total of 1,833 mothers consented to participate and were randomly assigned to the treatment or comparison group. After losing some participants due to their not receiving a home visit from a nurse or were not able to be found for the follow up, the final intent-to-treat sample included 649 mothers in the treatment group and 630 mothers in the comparison group. The baseline characteristics of the mothers in both groups were similar. Information was not provided on the race or ethnicity of either the treatment or comparison group participants.
For 58 percent of the treatment group and 59 percent of the comparison group, this was their first baby. Regarding age, in the treatment group sample, 10 percent of the mothers were younger than age 25, 59 percent were between ages 25 and 35, and 31 percent were older than age 35. In the comparison group sample, 7 percent of the mothers were younger than age 25, 64 percent were between ages 25 and 35, and 30 percent were older than age 35.
In regard to educational level, 14 percent of the treatment group sample had completed high school or less, 33 percent were in college, 22 percent had completed college, and 31 percent had completed some graduate studies. Of the comparison group sample, 13 percent had completed high school, 28 percent were in college, 25 percent had completed college, and 34 percent had completed some graduate studies. A total of 83 percent of the treatment group was married, 11 percent were not married but living with a partner, and 6 percent were not married. Similarly, a total of 81 percent of the comparison group was married, 11 percent were not married but living with a partner, and 8 percent were not married.
The questionnaire included questions about the mothers’ knowledge about crying and shaking, about the mothers’ behavior in the past month in response to crying and inconsolable crying, the number and relationship of caregivers other than the mother, and whether the mother had shared program information with any other caregivers. Because of a lack of prior research in this area, all measures of crying, safety knowledge, and behavior were developed for the study.
The Responses to General Crying Scale asked mothers how often they did each of the following with their infant in the past month: picked up their infant when she or he fussed or cried, put down the infant and walked away when they were frustrated, told other people who take care of their infant about the characteristics of infant crying, walked around with the infant when he or she fussed or cried, and told other people who take care of their infant what to do if they became frustrated with the infant’s crying. Response options ranged from 0 (did not do it), 1 (once or twice), 2 (3 to 5 times), 3 (6 to 10 times), to 4 (11 times to almost every day). The Responses to Inconsolable Crying Scale also asked mothers how often they did each of the following with their infant in the past month: passed the baby to someone else for awhile, put the baby down in a safe place for awhile, took a break from the sound of crying, and took the baby for a walk or drive. The Self-Talk Responses to Inconsolable Crying Scale used the same time frame and coding scheme as the other measures. Items included “telling yourself the crying would end,” “telling yourself your baby is okay,” “telling yourself there is nothing you can do,” and “telling yourself it was not your fault.”
Differences in mean scores for the treatment and comparison groups were computed for positive behavior (i.e., soothing, setting the baby down in a safe place, walking away) used for crying, positive behavior used for inconsolable crying, and self-talk during inconsolable crying. The study authors reported confidence intervals and p-values. Subgroup analyses were conducted.