Important goals of managing postoperative pain (POP) are to minimize pain and discomfort, facilitate the recovery process, and avoid complications [1] . Strong unrelieved POP increases the risk for developing chronic pain after surgery [2] - [4] . In spite of increased knowledge about pain, effective POP management is still a major challenge, and multiple studies have identified areas of poor clinical practice [4] - [11] . Nurses and physicians often underestimate pain [12] [13] , and inadequate communication about pain between nurses and patients remains a problem in pain relief [9] . Karlsten et al. [14] argued that POP management success requires active postoperative pain assessment, improved staff training, regular staff meetings, and audits with feedback to the staff involved. The Norwegian Medical Association [15] recommends using a pain-rating scale―the Numeric Rating Scale-11 (NRS-11), in which 0 represents no pain and 10 represents the worst pain imaginable―to assess and treat POP in accordance with the International Association for the Study of Pain (IASP) [1] . The NRS-11 is a reliable and valid scale for assessing and evaluating POP management [16] . Because nurses play an important role in assessing and treating POP, they need to understand the proper use of pain scales [16] [17] .

Several studies [18] - [20] have identified poor POP documentation in nursing records. In an investigation of the consistency between care given to patients postoperatively and what information is documented, De Marinis et al. [18] found that nursing records were inadequate for quality care evaluation because they did not include a comprehensive account of the care activities of the nurses.

Gunnarsdóttir et al. [21] conducted a systematic review of 11 experimental studies that evaluated the efficacy of educational programs aimed at improving the pain-management skills of health care professionals. Due to variations in methodology, patient population, setting, and intervention targets, only 4 of the 11 studies were relevant for the present study [22] - [25] . Francke et al. [22] [23] tested a comprehensive training program (eight three-hour sessions) aimed at surgical nurses in five Dutch hospitals. After the program’s completion, no increase in the use of pain-rating scales was found [22] . However, the study indicated a positive effect on patients’ pain intensity [23] . Ravaud et al. [24] found significant improvements in POP documentation and significant reductions in pain-intensity scores after 48-hour stays in surgical intervention units compared to stays of the same length in surgical control units. The intervention aimed at nurses included a one-hour educational program about pain and the use of a visual-analogue scale to assess pain. Michaels et al. [25] found no significant effect on POP documentation after an educational intervention in eight units compared to eight control units in which no intervention was conducted. This educational program comprised 20 - 30 minute lectures for staff followed by a video presentation.

Several comprehensive quality-improvement studies conducted between 2000 and 2005 have displayed positive results [14] [26] [27] . A pain-monitoring program for nurses proved to be effective in improving nurses’ assessment of pain and documentation of pain in nursing records [26] . Warrén Stomberg et al. [27] studied the impact of database documentation of POP management of an anesthesia organized, nurse-based, anesthesiologist-supervised acute pain service on surgical wards over a two-year period. They found that about 60% of the data charts were properly completed and documented in the database and remained the same over the two year period [27] . Karlsten et al. [14] found that a three-year quality-improvement study using annual audits and education improved the use of the NRS-11 in surgical wards. Crawford et al. [28] reported that significantly fewer patients experienced mild and moderate pain subsequent to an intervention composed of postoperative analgesic protocols and supported by education of staff and patients. However, the percentage of patients who experienced severe pain remained the same after the intervention [28] .

To our knowledge, only three studies with less comprehensive and expensive interventions have been conducted [24] [25] [28] . Because previous studies have shown different results regarding POP documentation and patients’ pain-intensity level, more knowledge is needed regarding educational interventions that may help to increase nurses’ use of the NRS-11 in POP management and to reduce patients’ pain-intensity level. This paper focuses on educational programs designed to enhance nurses’ use of assessment tools and documentation in POP management.

This study assessed whether a standardized educational program aimed at nurses could increase the use of the NRS-11 in documenting and reducing POP intensity level in hospitalized surgical patients.

This study assessed whether a standardized educational program could increase the documentation of pain and reduce the POP intensity level of hospitalized surgical patients. The results showed no significant difference in the frequency of POP documentation, which agrees with the findings of Michaels et al. [25] . The duration of the educational program in that study was similar to ours, although the content differed to some extent. In the Michaels et al. study, in addition to offering a video presentation after the educational session, four clinical nurse specialists conducted the education program [25] , whereas in the present study nursing students conducted the educational program with support from the authors. In Michaels et al.’s study, the discussion focused on the difference between acute and chronic pain, whereas the focus of the discussion in our study was on acute pain. Both programs offered discussions on common myths and barriers associated with pain management.

In contrast to our study, Ravaud et al. [24] found that an educational program for nurses led to significant improvements in POP documentation. The content of their educational program, which involved a 20 - 30 minute lecture, seemed quite similar to ours. In addition, their program was extended with a video presentation and individual feedback, and the main educators were an anesthetist who was an expert in pain management and a chief nurse. In our study, the main educators were students, and this may have influenced how important the nurses considered the message to be, which may have affected our results. It is interesting to note that Ravaud et al.’s assessment was performed48 hours after the intervention, whereas in our study it was performed after a minimum of three months. The studies of de Rond et al. [26] and Warrén Stomberg et al. [27] found positive effects on POP documentation. However, the more comprehensive interventions conducted in those studies may explain their positive results. Improving nurses’ knowledge and changing their attitudes toward pain management seems to take a significant amount of time and effort.

The discussion that followed the educational program in our study often concerned whether nurses could trust patients’ self-report of pain. In the educational program, we gave an example of how a patient can self-report a pain level of 7 on the NRS-11 and still retain the ability to read a newspaper. Some nurses questioned this example and stated they would not trust such a patient’s subjective report of pain. However, not trusting patients’ self-report of pain is seen as a barrier to effective POP pain relief [1] . As a lived, subjective experience, pain is difficult to measure, and it differs from other vital signs (pulse and blood pressure) that are objective and easily measured.

Previous studies have shown that nurses in general maintain low levels of documentation of their nursing

activities [18] [19] [30] . De Marinis et al. [18] found that nurses prioritize patient care and that they do more than they record. This finding may apply to our study. In the hospital where our study took place, pain should be documented primarily in the pain paper schema, but it can also be documented in the patient’s records. This is potentially confusing, because it may be perceived as a double system of documentation. The pain paper schema used by the hospital in this study is rather comprehensive, and it maybe too complex to be used for regular documentation by busy nurses. In Norway, however, nurses have a general obligation to document relevant observations and interventions [31] . POP management is one of many nursing activities that should be documented, but the failure to do so has no serious consequences in Norwegian hospitals today.

In this study, no significant reductions in the patients’ POP intensity levels were found three months after the education program. This result contrasts with the studies of Ravaud et al. [24] and Crawford et al. [28] , which found reduced POP intensity scores after an educational intervention. However, in Ravaud et al. [24] , the assessment was performed 48 hours after the intervention, compared to three months in our study. To maintain the effect of an intervention over time, it seems to be essential to establish routines that use continuous feedback and auditing, as recommended by Warrén Stomberg et al. [27] and Karlsten et al. [14] . Crawford et al. [28] used a medical protocol in addition to the educational intervention, which may explain the differences between the results of that study and those of ours.

The results of our study showed that the mean pain-intensity level conformed to the guidelines of the IASP [1] and the Norwegian Medical Association [15] , which recommend that the patient’s POP intensity level should be treated and preferably held at 3 or below (≤3) on the NRS-11 in the acute postoperative phase. The distribution of pain-intensity scores indicated that there was a group of patients that continued to have moderate (3.5 - 6.0) and severe (>6.5 - 10) pain, which is in line with other studies [28] [32] [33] .

Our study had several limitations. The inclusion of only one hospital reduces the generalizability of the results. Moreover, the study design would have been stronger if a control group had been included, and the exclusion of records from surgical patients with fewer than three NRS-11 documentations may have influenced the results. Finally, we collected data only from the pain paper schema and not from the patients’ records, which may represent a weakness of this study. We suggest three areas for future research, 1) nurses’ beliefs and attitudes as this remain a major barrier for optimal POP management and calls for nurses to audit their own practice [14] , 2) developing a health care culture that promotes optimal pain management which is strongly related to unit leadership, values held by the staff, nurse competency, and effective quality programs that include process and outcome indicators of pain management [14] [20] , and 3) implementation of the NRS-11 in the electronic record, because it would enable systematic data monitoring. Despite the fact that pain was assessed and registered as a vital sign and documented by nurses on a regular basis using an electronic device, Carr et al. [34] found that POP was suboptimal managed. However, Carr et al. [34] found that assessment and documentation increased using an electronic device which is a prerequisite for handling POP management.

The standardized educational program conducted as a single session in this study resulted in no increase in the frequency of POP documentation using the pain-rating scale (NRS-11) and no decrease of the POP intensity level in hospitalized surgical patients assessed after three months.

The hospital and the nursing college gave time and financial support to this quality improvement study.

We do not have any conflict of interest with any issue discussed in this article