The data for this study were obtained from a cross-sectional survey designed to explore pain and quality of life in patients in nursing homes in central Norway. The data were collected from September 2005 to May 2006.
In-patients aged 65 years and over from seven Norwegian nursing homes were included in the study. Central Norway consists of three counties (Nord Trøndelag, Sør Trøndelag and Møre and Romsdal). Nursing homes are owned by municipalities and their funding depends on the ranking of priorities in municipal budgets. This can lead to different levels of qualified staff among nursing homes and variations in care, pain assessment and pain management. There are also policy differences among municipalities governing which patients receive nursing-home care rather than community care. To achieve a representative sample, nursing homes were stratified into six strata, by urban and rural status, in each of the three counties in Central Norway. One nursing home was drawn from each stratum. In Møre and Romsdal, two nursing homes were included from rural areas because of low patient numbers in these nursing homes.
Patients were excluded if they had been in the nursing home for less than one week, had a short life expectancy (estimated by the nursing staff) or were younger than 65 years. All eligible patients were scored on Mini Mental State Examination (MMSE) by the investigator (KT), and the patients were categorized as nonverbal if they scored zero on this test.
Data collection
Demographic data (age, gender, education and marital status), medical diagnoses (including pain-related diagnosis and dementia), and prescribed treatment were collected for all patients from their medical or nursing records by the investigator (KT).
Prescribed medications were classified according to the Anatomical Therapeutic Chemical (ATC) System [27] and were from ATC groups musculoskeletal and analgesic (anti-inflammatory and anti-rheumatic products, topical products for joint and muscular pain, muscle relaxants, anti-gout preparations, drugs for treatment of bone disease, and analgesics). Pain-relieving medication was categorized according to the work done by Nygaard et al. [2]: no opioids, weak opioids, strong opioids, and other pain-related medication (topical products for joint and muscular pain, muscle relaxants, anti-gout preparations, and drugs for the treatment of bone disease).
Pain-related diagnoses were based on previous research and consisted of fractures, knee and hip prostheses, osteoporosis, stroke, cancer, migraine and headache, myalgia, arthritis, amputation, angina pectoris, herpes zoster, low-back pain, duodenal ulcers, ventricular ulcers and gastritis [1, 2, 28].
Daily life functioning
Barthel's Activities of Daily Living Index (ADL) was used as a screening instrument for patients' daily life functioning. This 10-point scale measures patients' degree of self-reliance, with a total score ranging from zero to 20. Lower scores indicate greater dependence on nursing care [29]. ADL scores below 5 indicate high dependency, 5 to 8 indicate medium dependency, 9 to 12 indicate low/medium dependency and scores from 13 to 20 indicate low dependency [30]. ADL data were collected from patients' records, by the investigator (KT), and validated by a registered nurse.
Pain
The Doloplus-2 consists of a list of 10 items divided into three subgroups: five somatic items (somatic complaints, protective body postures adopted at rest, protection of sore areas, expression, sleep patterns), two psychomotor items (washing and/or dressing, mobility) and three psychosocial items (communication, social life, problems of behaviour) [22]. Each item is scored from 0 to 3, where 0 is 'absent' and 3 is 'the highest score of the behaviour'. This gives a range from 0 to 30, with higher scores indicating more pain behaviours. The cut-off score between 'pain' and 'no pain' was set at 5, as recommended by the scale's developers [22]. It is not necessary to have responses for all items on the scale, and the instructions for use of Doloplus-2 emphasize not scoring those items that are judged as inappropriate for a given patient [22].
The Doloplus-2 was administered by the primary nurse (the registered nurse with the best knowledge of the patient's behaviour) [15, 22, 26]. This nurse cared for the patient regularly and needed to be present for the two days prior to assessing the patient. Before data collection started, the researcher increased staff awareness of patients' pain by teaching about pain and Doloplus-2. Staff received both oral and written information about how to use the Doloplus-2. They were told not to score the items on the Doloplus-2 if they were inappropriate for the given patients and the scoring should only be related to pain behaviours [22]. The scoring should also be done during mobilization, if possible. The researcher was also available to support them during the data collection.
Immediately before applying the Doloplus-2, the primary nurse answered a single question: 'Do you believe that this patient is experiencing pain?' Response options were 'no', 'yes' or 'don't know'. This measurement was done to compare the results with the Doloplus-2 scoring done by the same nurse.
Ethics
As patients in this study were cognitively impaired, guidelines from the Ministry of Health and Care Service in Norway were followed when recruiting [31]. Relatives of patients or their legal guardians received written information prior to the study and consented on their behalf. Patients received oral information prior to the study and were excluded if they declined to participate, even if their relatives/legal guardians had consented on their behalf.
The Regional Committees for Medical Research in Ethics, Southeast Norway, the Norwegian Social Science Data Services and the Ministry of Health and Care Service approved the study.
Statistics
Descriptive statistics were used to present demographic and clinical characteristics of the sample and gain an overview of not scored items on Doloplus-2. The percentages of minimum and maximum scores were calculated by assessing the percentages of lowest (0) and highest possible scores on the subscales (6, 9 and 15, respectively) and for the total questionnaire [32]. Mean scores are also calculated for the items, the subscales and the total questionnaire.
Cronbach's alpha coefficients were calculated to assess the internal consistency reliability of Doloplus-2. The alpha coefficient was calculated for the total questionnaire and for subscales. Alpha was also used to explore whether scales could be shortened by the deletion of single items. If Cronbach's alpha changes little when an item is deleted, then the item is a candidate for being removed from the scale [32]. In accordance with Fayers and Machin [30], an alpha above 0.90 was taken to indicate acceptable reliability for individual patient assessment.
The criterion validity was calculated by comparing registered nurses' subjective and Doloplus-2 pain assessments for each patient by Fisher's exact test. Comparison of the groups in respect of pain-related diagnoses and pain management was also calculated by Fisher's exact test.
The statistical software SPSS for Windows v.16.0 was used for analyses. A two-tailed P value below 0.05 was considered statistically significant.