Abstract

Lena MÃ¥rtensson* and Ingrid Bergh

Assessing pain in relation to childbirth is one of the midwife’s more important tasks. However, pain research shows that health care professionals often assess patients’ pain inaccurately. The Visual Analogue Scale (VAS) is one of the most used instruments for assessing pain and pain relief both in research and clinical practice. On the other hand, a patient’s verbal report is considered to be the single most reliable indicator of how much pain the patient is experiencing. The aim of this study was to compare women’s verbally reported effect of treatment for labor pain with changes in VAS scores. This comparative prospective study was carrying out on a labor ward with approximately 2,500 deliveries annually in western part of Sweden. Women (n=122) at gestational week 37 to 42 with spontaneous onset of labor, requesting pain relief, were randomized to one of two treatments: acupuncture or sterile water injections. Pain was assessed on a VAS before as well as 30, 60, 90, 120, 150 and 180 min after treatment. Within two hours after delivery the women were asked to verbally report the effectiveness with the treatment. Main outcome measure was agreement between VAS scores and verbal reports. Non-parametric tests were used. All tests were two-tailed at the significance level p< 0.05. The distribution of the VAS scores 30 min after administration of pain relief showed that the women verbally responding that treatment was “very effective”, also rated their pain significantly lower (p< 0.001) on the VAS, compared to the women verbally reporting otherwise. A moderate correlation (r = 0.56; p< 0.001) was obtained between VAS-scored pain change after 30 min and verbally reported pain relief effect. The women who stated that treatment was “very effective” also rated their pain significantly lower at 30, 60 and 90 min on the VAS, compared to baseline. This study confirms that verbal reports and changes in VAS scores are reliable indicators of treatment effect for labor pain. It might, however, be valuable to combine VAS scores with verbal reports for a more extensive assessment of treatment effect.