A randomized comparative study assessing efficacy of pain versus comfort scores.

CONTEXT: Use of language with negative emotional content is likely to increase patient's pain and anxiety. AIMS: We designed a single-blinded randomized study to compare pain scores with comfort scores and to determine whether the technique of pain assessment affects patient's perceptions and experience. SUBJECTS AND METHODS: After cesarean section, 180 women were randomized before postanaesthesia interview into two groups. Group P women were asked to rate their pain on a 0-10-point verbal numerical rating scale (VNRS) for pain while Group C women were asked to rate their comfort on a 0-10-point VNRS for comfort. All women were asked whether the surgical wound was associated with injury or healing. The primary outcomes were to compare the incidence of reported pain and to assess pain severity as measured by a 0-10-point VNRS for pain compared with an equivalent inverted VNRS for comfort. The secondary outcomes were whether the wound was associated with injury or healing. STATISTICAL ANALYSIS USED: Data were analyzed using Student's t-test and nonparametric Mann-Whitney U-test, performed at a significance level of α =0.05.
RESULTS: In Group P, 62 women (68.9%) reported pain compared with only 49 women (54.4%) in Group C (P < 0.05). There were no significant differences between groups for VNRS at rest and on movement. In Group P, thirty women (33.33%) reported sensations as injury compared with only 11 women (12.22%) in Group C (P < 0.001).
CONCLUSIONS: Assessment of pain using positive word like comfort decreases its incidence with no effect on its severity when measured by comfort score and also affects patient's postsurgical perceptions.

RCT Entities:   Population Interventions Outcomes

Introduction

Communication skill of the medical practitioners is increasingly being recognized to have a significant impact on their patients' perceptual experiences. Use of language with negative emotional content before potential noxious stimuli is likely to increase patient's pain and anxiety.[1] Warning patient during intravenous cannula insertion or before local anesthetic infiltration using words such as “big bee sting” that refers to negative experience may be unhelpful, however, use of gentler words such as “numbing the area” improves pain perception and patient comfort.[23] With the use of brain imaging, it has been observed that pain modulation occurs in the anterior cingulate cortex which links the limbic system with the sensory cortex when a negative suggestion is given.[45] The word “pain” functions as a negative suggestion which elicits a subconscious change in a patient's mood, perception, or behavior.[6]

Various methods have been designed to assess pain for postoperative pain management. In clinical practice, simple scales such as visual analog scale (VAS) or verbal numerical rating scale (VNRS) are widely used.[7] Recently, studies have documented that the use of word “comfort” rather than the word “pain” may affect patient's experience of their recovery.[8910] However, further investigations are needed to validate the results of these studies in our patient population.

Thus, we designed a single-blinded randomized study to investigate how standard pain scores compare with comfort scores after cesarean section and to determine whether the technique of pain assessment affects patient's perceptions and experience after cesarean section.

Subjects and Methods

This study was approved by the local Institutional Ethics Committee and registered with the www.ctri.nic.in (CTRI/2017/03/008248). After cesarean section and before postanaesthesia review, 180 women were randomly allocated into two groups of ninety patients each as per computer-generated randomized list. According to previously validated structured questionnaire, women were asked to rate their pain in Group P and to rate their comfort level in Group C. Women with age <18 years, deaf and dumb patients, patients with intellectual disability, and with a history of chronic pain or opiate abuse were excluded from the study.

All eligible women were assessed and interviewed by one of the researchers between 10 and 30 h after the cesarean section. Participants were blinded to group allocation by being unaware about the nature of intervention, but the assessors were not unaware of the group. An informed written consent to take part in the study was obtained after the postanaesthesia interview to keep the participants blinded to the study.

Group P women were asked the structured questionnaire [Table 1] to rate their pain from surgical trauma. They were asked “You have had a childbirth after surgery. So, I would like to rate your pain from the surgical trauma” followed by “Do you have any pain?” They were then asked to quantify their postoperative pain, at rest and on shifting to lateral position, on a 0–10-point VNRS, where “0” was “no pain” and “10” was “the worst pain imaginable.” A VAS was also used, where one end of the scale was marked as “least pain” and the other end as “most pain,” and there was a 0–10 cm scale on the reverse side of the VAS [Figure 1a]. These women were then asked to rate their worry caused by the surgical trauma on a 0–10-point VNRS, where “0” was “no worry” and “10” was “most worrisome imaginable,” whether they were comfortable and whether they required additional analgesia.

Table 1

Structured questionnaire for Group P and Group C

Figure 1

Visual analog scale for pain and for comfort. (a) Pain visual analog scale. (b) Comfort visual analog scale

Group C women were asked the structured questionnaire [Table 1] to rate their comfort level. They were asked “You have had your childbirth after surgery and your wound is healing. So, I would like to rate your comfort level” followed by “Are you comfortable?” They were then asked to quantify their comfort level, at rest and on shifting to lateral position, on a 0–10-point VNRS, where “0” was “no comfort” and “10” was “most comfort.” A VAS was also used, where one end of the scale was marked as “most comfort” and the other end as “least comfort,” and there was a 0–10 cm scale on the reverse side of the VAS [Figure 1b]. These women were then asked to rate their worry caused by the healing on a 0–10-point VNRS, where “0” was “no worry” and “10” was “most worrisome imaginable,” whether they had any pain and whether they required additional analgesia. Women in both the groups were asked their perceptions about the sensations after surgery and whether they prefer to be asked about their comfort level or pain level.

Our primary outcome was to assess the incidence of reported pain and pain severity as measured by a 0–10-point VNRS for pain compared with an equivalent inverted VNRS for comfort. Our secondary outcomes included pain severity as measured by a VAS for pain compared with VAS for comfort; whether the surgical wound was worrisome; the level of worry as measured by a 0–10-point scale; whether the patient required additional analgesia; whether the patient preferred to be asked about their comfort level or pain level; whether the patient considered the postoperative wound to be injury and disability or healing and recovery.

Power of study

The sample size was estimated from the results of previous study.[10] In Group P, 79% women answered that they were comfortable whereas in Group C, 94% of women were comfortable. Our sample size came out to be ninety participants per group at power of 90% with α = 0.05, β = 0.20, and confidence interval of 95%.

Statistical analysis

Discrete categorical data were presented as n (%); continuous data were written as either in the form of its mean and standard deviation or in the form of its median and interquartile range, as per the requirement. The normality of quantitative data was checked by measures of Kolmogorov–Smirnov tests of normality. For normally distributed, t-test was applied for statistical analysis of two groups. For skewed data or ordered categorical data, nonparameteric Mann–Whitney U-test was used for statistical analysis of two groups. For categorical data, comparisons were made by Pearson Chi-square test or Fisher's exact test as appropriate (%). All the statistical tests were two-sided and were performed at a significance level of α =0.05. The analysis was conducted using IBM SPSS Statistics (version 22.0).

Results

Participant flow diagram is shown in Figure 2. After cesarean section, 183 women were assessed for eligibility, out of which, three were excluded as they were not meeting the inclusion criteria due to intellectual disability. One hundred and eighty women were then randomized, interviewed, and analyzed. There were no clinically significant differences between the two groups with respect to patients' characteristics, anesthetic technique, and postoperative analgesia as shown in Table 2.

Figure 2

Consort diagram

Table 2

Baseline patient characteristic data in Groups P and C

Table 3 shows the number of women who reported pain, VAS, and VNRS scores at rest and on shifting to lateral position, patient perceptions of the postoperative wound, and worry scores in both the groups.

Table 3

Women reporting pain, verbal numerical rating scale, and visual analog scale at rest and movement, patient perceptions of postoperative wound

In Group P, 62 women (68.9%) reported pain while only 49 women (54.4%) in Group C reported pain when asked “Do you have any pain?” (P < 0.05). However, when women were asked “Are you comfortable?,” 79 women (87.8%) in Group P and 80 women (88.9%) in Group C stated that they were comfortable with no significant difference between both the groups (P = 0.81). There were no significant differences between Groups P and C for VNRS at rest (2 [0-3] vs. 1 [0-2], P = 0.188) and VNRS on shifting to lateral position (5 [3-6] vs. 5 [3-5], P = 0.119). Similarly, no significant differences were found between Groups P and C for VAS at rest (10 [0-30] vs. 10 [0–22.5], P = 0.733) and on shifting to lateral position (45 [30-50] vs. 50 [50-70], P = 0.828).

In Group P, 41 women (45%) compared to 30 women (33.33%) in Group C, stated that they were worried (P = 0.093) with similar worry score (2 [0-5]) in both the groups.

In Group P, 30 (33.33%) out of ninety women reported sensations as injury and disability and 59 (65.55%) women reported healing and recovery. In contrast to Group C, where only 11 women (12.22%) reported sensations as injury and disability while 78 (86.66%) reported healing and recovery (P < 0.001).

Women in both the groups prefer being asked about their comfort level than their pain level. In Group P, 61 (67.77%) and in Group C, 67 (74.44%) preferred to be asked for comfort level. Out of 180 women interviewed, 16 women had no preference for pain or comfort level.

Discussion

This is a single-blinded, randomized, observational study investigating the effect of pain assessment using the word comfort on the incidence of reported pain, severity of pain, and patients' postsurgical perceptions. Recently, studies have shown that women after cesarean section are more likely to report pain when asked “Do you have any pain?” compared with when women are asked “Are you comfortable?” for assessment of pain.[89] In our study also, we found that the incidence of reported pain was significantly more in Group P compared to Group C. This might be due to the reason that use of negative words gives a negative suggestion of sensations as pain that might have not been experienced otherwise.

However, when asked about comfort, majority of the patients (88%) in both the groups stated that they were comfortable and this included those also who reported pain on asking about pain. Thus, as shown in other studies,[23] use of positive word like comfort in our study reduced pain perception and improved patient comfort.

In 2013, Chooi et al. compared pain with comfort scores in 300 postcesarean section women and found pain scores to be higher than inverted comfort scores. However, in our study, there were no significant differences between comfort and pain scores between both the groups. This lack of difference between comfort and pain scores may be because some patients who were comfortable might have experienced pain when asked about it or some women might have stated that they were comfortable despite being in pain. Our results are similar with a study done by Chooi et al. in 2011, on 232 patients where they found no difference in pain scores between both the groups and no difference in analgesia requirement.

Significantly more number of patients in Group P perceived postoperative sensations as injury and disability and this may be because of negative suggestions used in questionnaire in contrast to Group C where majority perceived postoperative sensations as healing and recovery. Thus, as shown by Chooi et al.[10] in 2013, use of positive word like comfort for pain assessment improved patients' perceptions of postsurgical wound in our study.

Women preferred comfort scale because word pain reminded them of their suffering while word comfort provided them positive connotation.

Our study has a number of limitations. Since there is no exact antonym for pain, comparison of pain with comfort may be questioned. For statistical comparison between pain and comfort groups, comfort scores are inverted such that the anchors are reversed, that means, “most pain” translated to “least comfortable” and “least pain” to “most comfortable.” Furthermore, inverted comfort scores have been compared with pain scores; however, it is difficult to be certain whether a particular pain score, for example, 4 of 10 pain actually corresponds to a 6 of 10 for comfort.

Women were questioned at a separate time to the usual ward rounds by obstetric and anesthetic teams, and our study does not consider how patients were questioned by doctors and nurses about their pain before the assessment in this study.

The patients were interviewed once and not followed up because of the limited resources available; hence, the need for additional analgesics was not tracked over time.

Conclusion

Thus, we would like to conclude that assessment of pain using positive word like comfort decreases its incidence but does not affect its severity when measured by comfort score. Patient's perceptions and experience after surgery can be improved by communicating with them using words such as comfort that provide them positive connotation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.