///2015 Abstract Details
2015 Abstract Details2019-08-02T16:54:43-06:00

The Labor Pain Questionnaire: High Sensitivity to Change in Women Receiving Labor Epidural Analgesia

Abstract Number: F-65
Abstract Type: Original Research

Pamela J ANGLE MD FRCPC MSc DPHIL (c)1 ; Christine Kurtz-Landy RN, PhD2; Alex Kiss PhD3; Jasmine Djordjevic BSc Hons, CCRP4; Jon Barrett M.B.Bch., FRCOG, MD, FRCSC5; Alanna Kibbe RM6

Introduction: The Labor Pain Questionnaire(LPQ)is a 22-item health-specific psychometric instrument developed to measure women's pain experiences during childbirth. Our recent work showed excellent test-retest reliability, internal consistency, and adequate sensitivity to change and responsiveness of the LPQ and its subscales during early labor without pain relief. The current study examined the LPQ's sensitivity to change and validity in women receiving labor epidural analgesia.

Methods: After informed consent, ASA 1-2 laboring women with term fetuses were recruited. Women were fluent in English, >18 years of age, ≤6cm cervical dilatation and contracting ≥3 minutes apart. Participants answered the LPQ in mixed or standard item format during 2 test sessions. The first test session (T1) occurred within an hour prior to epidural insertion; the second (T2) was answered 20mins following epidural drug administration. Both tests were conducted by the same trained interviewer. Concurrently administered pain tools(NRS, verbal pain rating scale (VPRS),Pain Mastery Scale (PMS)) were also completed during each session, permitting assessment of their convergent validity with the LPQ. Changes in pain between tests were rated using the Patient Global Impression of Change Scale(PGICS). Raw scores were transformed to percentage scores to ensure even representation of subscales in LPQ composite/total scale scores. Sensitivity to change of the LPQ was examined using the t-statistic(paired-t test),Effect size (ES), and Standardized Response Mean(SRM) LPQ scores corresponding to response levels on the PGICS, VPRS and PMS were determined.

Results: 51 women completed the study; most (50/51)described much or very much improvement in their pain at 20minutes post epidural drug administration. Four women described minimal improvement;1 described no change in pain. Raw scores differed significantly between T1 and T2 for LPQ composite and all subscale scores(t-statistic(df-49) 3.8 to 12.2, p<0.001).Effect size values were large for raw LPQ composite(2.1)and subscale scores(Enormity of the Pain(1.4),Uterine Contraction pain(2.2), Backpain/Longhaul(2.0), Fear/Anxiety (1.1), and Birthing Pain(0.86)). Correlations between raw LPQ composite scores and subscale scores during Test 1 and Test 2 were r= 0.17 to 0.39. Standardized Response Means ranged from 0.65 to 1.9 and were interpreted as large based on study-derived ES thresholds using methods described previously. Strong correlations were found between raw LPQ composite and NRS scores at T1 (0.78)and T2 (r=0.83). Correlations were moderate to strong between LPQ composite and VPRS scores at T1(r=0.5) and T2(r=0.78) and between LPQ and PMS scores at T1(0.67) and T2 (0.82). All were statistically significant (p<0.001).

Conclusions: LPQ composite and subscale scores showed high levels of sensitivity to change and evidence of convergent validity with other pain tools in women receiving epidural analgesia during early labor.

SOAP 2015