Sex differences in response to experimental pain are commonly reported in systematic reviews in the adult literature. The objective of the present research was to conduct a systematic review and meta-analysis of sex differences in healthy children's responses to experimental pain (e.g., cold pressor, heat pain, pressure pain) and, where possible, to conduct analyses separately for children and adolescents. A search was conducted of electronic databases for published papers in English of empirical research using experimental pain tasks to examine pain-related outcomes in healthy boys and girls between 0 and 18 years of age. Eighty articles were eligible for inclusion and were coded to extract information relevant to sex differences. The systematic review indicated that, across different experimental pain tasks, the majority of studies reported no significant differences between boys and girls on pain-related outcomes. However, the meta-analysis of available combined data found that girls reported significantly higher cold pressor pain intensity compared to boys in studies where the mean age of participants was greater than 12 years. Additionally, a meta-analysis of heat pain found that boys had significantly higher tolerance than girls overall, and boys had significantly higher heat pain threshold than girls in studies where the mean age of participants was 12 years or younger. These findings suggest that developmental stage may be relevant for understanding sex differences in pain.
The field of pediatric pain research began in the mid-1970s and has undergone significant growth and development in recent years as evidenced by the variety of books, conferences, and journals on the topic and also the number of disciplines engaged in work in this area. Using categorical and bibliometric meta-trend analysis, this study offers a synthesis of research on pediatric pain published between 1975 and 2010 in peer-reviewed journals. Abstracts from 4256 articles, retrieved from Web of Science, were coded across 4 categories: article type, article topic, type and age of participants, and pain stimulus. The affiliation of the first author and number of citations were also gathered. The results suggest a significant increase in the number of publications over the time period investigated, with 96% of the included articles published since 1990 and most research being multiauthored publications in pain-focused journals. First authors were most often from the United States and affiliated with a medical department. Most studies were original research articles; the most frequent topics were pain characterization (39.86%), pain intervention (37.49%), and pain assessment (25.00%). Clinical samples were most frequent, with participants most often characterized as children (6-12 years) or adolescents (13-18 years) experiencing chronic or acute pain. The findings provide a comprehensive overview of contributions in the field of pediatric pain research over 35 years and offers recommendations for future research in the area.
This systematic review evaluated the effectiveness of simple psychological interventions for managing pain and fear in adults undergoing vaccination or related common needle procedures (ie, venipuncture/venous cannulation). Databases were searched to identify relevant randomized and quasi-randomized controlled trials. Self-reported pain and fear were prioritized as critically important outcomes. Data were combined using standardized mean difference (SMD) or relative risk (RR) with 95% confidence intervals (CI). No studies involving vaccination met inclusion criteria; evidence was drawn from 8 studies of other common needle procedures (eg, venous cannulation, venipuncture) in adults. Two trials evaluating the impact of neutral signaling of the impending procedure (eg, "ready?") as compared with signaling of impending pain (eg, "sharp scratch") demonstrated lower pain when signaled about the procedure (n=199): SMD=-0.97 (95% CI, -1.26, -0.68), after removal of 1 trial where self-reported pain was significantly lower than the other 2 included trials. Two trials evaluated music distraction (n=156) and demonstrated no difference in pain: SMD=0.10 (95% CI, -0.48, 0.27), or fear: SMD=-0.25 (95% CI, -0.61, 0.10). Two trials evaluated visual distraction and demonstrated no difference in pain (n=177): SMD=-0.57 (95% CI, -1.82, 0.68), or fear (n=81): SMD=-0.05 (95% CI, -0.50, 0.40). Two trials evaluating breathing interventions found less pain in intervention groups (n=138): SMD=-0.82 (95% CI, -1.21, -0.43). The quality of evidence across all trials was very low. There are no published studies of simple psychological interventions for vaccination pain in adults. There is some evidence of a benefit from other needle procedures for breathing strategies and neutral signaling of the start of the procedure. There is no evidence for use of music or visual distraction.