A Questionnaire to Evaluate the Knowledge and Attitudes of ... - IOV

Vol. 33 No. 6 June 2007 Questionnaire on Pain Knowledge729Table 1Percentage of Correct Answers, Percentage of ‘‘Neither Agree Nor Disagree’’ Answers, and Missing Dataof the Initial 21-Item QuestionnaireItems in the QuestionnairePercentage ofCorrect Answers(95% CI)Percentage of‘‘NeitherAgree NorDisagree’’AnswersPercentageofMissingData1. Giving narcotics on a regular schedule is preferred over ‘‘p.r.n.’’ schedule 81.1 (80.0e82.2) 7.9 0.3for continuous pain. (a)2. A patient should experience discomfort prior to giving the next dose of 45.2 (43.9e46.6) 15.4 0.8pain meds. (d)3. The preferred rule of administration of narcotic pain relievers to patients 55.8 (54.4e57.1) 25.1 1.4with pain is intramuscular. (d)4. When a patient requests increasing amounts of analgesics to control pain, 37.8 (36.4e39.1) 35.1 1.4this usually indicates that the patient is psychologically dependent. (d)5. Patients receiving narcotics on a ‘‘p.r.n.’’ basis may be likely to develop 40.0 (38.6e41.3) 21.8 1.0clock-watching behaviors. (a)6. The most accurate judge of the intensity of the patient’s pain is the 64.1 (62.8e65.4) 22.0 0.7patient. (a)7. When a patient in pain is receiving analgesic medication on a ‘‘p.r.n.’’ 39.5 (38.2e40.9) 20.6 1.0basis, it is appropriate for the patient to request pain meds before the painreturns. (a)8. Staff can always pick up cues from children that indicate that they are in 46.4 (45.0e47.8) 28.6 1.3pain. (d)9. Because narcotics can cause respiratory depression, they should not be 37.2 (35.8e38.5) 32.7 2.2used in pediatric patients. (d)10. Children cry all the time, therefore, diversional activities are indicated 45.5 (44.1e46.9) 29.1 1.1rather than actual pain meds. (d)11. The most suitable dose of morphine for a patient in pain is a dose that 45.0 (43.6e46.4) 18.9 3.5best controls the symptoms; there is no maximum dose (i.e., a level thatmust not be exceeded) for morphine. (a)12. It may often be useful to give a placebo to a patient in pain to assess if he 24.3 (23.1e25.5) 14.7 2.7is genuinely in pain. (d)13. For effective treatment of cancer pain it is necessary to continuously assess 91.2 (90.4e92.0) 3.0 2.5the pain and the efficacy of the therapy. (a)14. It is a patient’s right to expect total pain relief as a consequence of 70.9 (69.6e72.1) 14.9 2.8treatment. (a)15. Lack of pain expression does not mean lack of pain. (a) 83.5 (82.5e84.5) 7.3 2.616. Distraction, for example, by the use of music or relaxation, can decrease 67.4 (66.1e68.7) 20.0 2.6the perception of pain. (a)17. Estimation of pain by an M.D. or R.N. is as valid a measure of pain as 46.2 (44.8e47.6) 28.5 3.1a patient’s self-report. (d)18. Patients having severe chronic pain often need higher dosages of pain 46.6 (45.2e48.0) 24.5 3.4meds than patients with acute pain. (a)19. Increasing analgesic requirements are signs that the patient is becoming 25.0 (23.7e26.1) 34.7 2.7addicted to the narcotic. (d)20. If a patient (and/or family member) reports that a narcotic is causing 31.3 (30.0e32.6) 35.7 3.5euphoria, s/he should be given a lower dose of the analgesic. (d)21. 25% of patients receiving narcotics around the clock become addicted. 30.2 (28.9e31.4) 35.1 3.3(d)Total 50.2 (49.7e50.7) 22.7 2.0(a) ¼ Correct answer: ‘‘agree’’ or ‘‘strongly agree.’’(d) ¼ Correct answer: ‘‘disagree’’ or ‘‘strongly disagree.’’p.r.n. ¼ Pro re nataet al. study 6 (questions 1, 2, 4e10, 15e21), andfive were prepared by the authors (questions 3,11e14).The questionnaire was handed to the headnurse of each hospital ward, who undertookto give it to all the doctors and nurses in theward; all were instructed to keep the questionnaireanonymous but to indicate their qualificationsand the name of the ward. Thequestionnaire was to be completed quickly,without consulting medical texts.Psychometric AnalysisIn developing a scale from the initial questionnaire,we considered one sequence of exploratoryand confirmatory analysis in threephases.

730 Zanolin et al.Vol. 33 No. 6 June 2007Principal Component Analysis Phase. To identifythe number of the underlying components ofthe initial questionnaire, the Pearson’s correlationmatrix was explored by means of PrincipalComponent Analysis (PCA); 19 items weaklycorrelated with others (r < 0.15) had been previouslyexcluded from this analysis. The numberof components was determined on thebasis of eigenvalues of the correlation matrixgreater than 1, and by looking for sharp breaksin the size of the eigenvalues using a scree plot.Varimax rotation and item-component correlations,i.e., ‘‘component loading,’’ greater than0.32, in absolute value, were chosen to identifya simple component structure.Multiple Correspondence Analysis Phase. MultipleCorrespondence Analysis (MCA) or HomogeneityAnalysis (HOMALS) 20 is designed totest the items’ internal homogeneity and reliabilityand the Likert equidistance of theitem option responses for each dimension ofthe PCA. This method uses the Likert pointsas nominal categories responses and enablesoptimal grading for each category responseof the Likert questions (called ‘‘optimalweights’’); consequently, an ‘‘optimal score’’for each subject could be obtained. The optimalscore of a subject is the sum of the optimalweights of the item options chosen. Accordingto the criterion of the internal consistency,MCA computes a homogeneity index (called‘‘Guttman’s eta’’), and the ‘‘optimal reliability’’determined by Cronbach’s alpha coefficient isa one-to-one transformation of Guttman’s eta.Good internal consistency has been suggestedif Cronbach’s alpha exceeds 0.70, and good homogeneityhas been suggested if Guttman’s etavalue exceeds 0.30. The assumed equidistanceacross Likert points is checked by plotting theoptimal weights vs. Likert points (called ‘‘transformationplot’’); we should expect a straightlineplot for each item if equidistance is acorrect assumption.Confirmatory Factor Analysis Phase. A ConfirmatoryFactor Analysis (CFA) 19 model withone factor is fitted, considering Likert or optimalpoints of the item option responses set foreach dimension of PCA. The construct validityof the assumed unidimensionality is evaluatedfrom the CFA model fitting solution by theStandardized Root Mean Squared Residual(SRMR) index; this measures the residual reductionof the model (mis)fit as one factor isadded to the null model of uncorrelated items.Unidimesionality is suggested if SRMR index isless than roughly 0.05. Item-factor correlations,i.e., ‘‘factor loading,’’ and McDonald’somega reliability 21 are also computed. Correlations>0.32 in absolute value and omega >0.70are the chosen cut offs to corroborateunidimensionality.New QuestionnaireOnce the new questionnaire had been designed,results according to the new versionwere computed considering both the correct/incorrectmodality and the score of answers.In the latter case, missing datareferring to any single item were assigned thevalue of the median of all the subjects, anda standardized score was calculated as summatedscore/maximum score, expressed asa percentage, with 100% indicating the mostfavorable level of ‘‘knowledge and attitudes towardthe approach and treatment of pain’’ and0% the least favorable. Differences in scoresbetween professional categories (physiciansand nurses), hospital departments (Anesthesiologyand Emergency, Medicine, Surgery, andother departments), and geographical zones(northern, central, and southern Italy) weretested through ANOVA. Descriptive data analysesand PCA/MCA were performed using SPSSsoftware, version 13.0 (http://www.spss.com),and CFA was provided by Mplus software,version 3.13 (http://www.statmodel.com).ResultsCorrect Answer Distribution of the InitialQuestionnaireThe overall percentage of correct answers ofthe 4,961 caregivers who completed the initialquestionnaire was 50.2% (95% Confidence Interval[CI]: 49.7%e50.7%), corresponding toan average number of correct answers of10.5/21 (Table 1). The question with the highestpercentage of correct answers (91.2%) wasq13 (‘‘For effective treatment of cancer pain, itis necessary to continuously assess the pain andthe efficacy of the therapy’’ [the correct answeris ‘‘agree’’]). The question with the lowest

Vol. 33 No. 6 June 2007 Questionnaire on Pain Knowledge731number of correct answers was q12 (‘‘It may oftenbe useful to give a placebo to a patient inpain to assess if he is genuinely in pain’’ [thecorrect answer is ‘‘disagree’’]). In Table 1, thepercentage of missing answers is also shown:it tends to be higher from q11 onward, becausethe questions were written on the backof each page of the questionnaire and perhapssome interviewees did not see them.There was a statistically significant difference(P < 0.001) in the number of correct answersbetween doctors (12/21; 57.3%) andnurses (10/21; 47.6%). There were also statisticallysignificant differences (P > 0.001) betweenAnesthesiology and Emergency (11.6/21; 55.2%), with the highest mean score, andother departments (10.6/21; 50.5%), Medicine(10.5/21; 50.2%), and Surgery (10.2/21;48.7%). The highest percentage of correctanswers was reached in central Italy (11.0/21;52.1%), followed by southern Italy (10.5/21; 50.1%) and northern Italy (10.2/21;48.7%). These differences were again statisticallysignificant (P < 0.001). Questions 4, 9,19, 20, and 21 present the highest percentageof ‘‘neither agree nor disagree’’ answers.Psychometric AnalysisConsidering the correlation matrix betweenthe items of the initial questionnaire, sevenquestions (q5, q6, q7, q11, q14, and q18)were excluded from the PCA as they wereweakly correlated (r < 0.15) with the vast majorityof the other items. As q19 was almostequal to q4 (r ¼ 0.44), it was also excluded.PCA identified two dominant components(eigenvalues > 1), explaining 33% of the totalvariance and 60% of the pairwise correlationsof the 14 questions examined. Componentloading patterns, after Varimax orthogonal rotationof the correlation matrix, are shown inTable 2. The first component includes 10 itemsabout ‘‘the knowledge and attitudes towardpain of the health care providers’’; the secondcomponent includes four items containingquestions with a high percentage of correct answersthat are not particularly useful for theidentification of a valuable dimension, andtherefore, has not been considered in the followingMCA/CFA phases. These results arethe same as those obtained when doctors’and nurses’ data were analyzed separately.ItemTable 2Component Loadings aPrincipalComponent 1PrincipalComponent 2Uniquenessq1 0.137 0.529 0.580q2 0.529 0.171 0.662q3 0.494 0.182 0.712q4 0.636 0.067 0.586q8 0.334 0.098 0.516q9 0.606 0.056 0.628q10 0.618 0.061 0.614q12 0.541 0.233 0.601q13 0.048 0.744 0.441q15 0.043 0.685 0.499q16 0.089 0.617 0.607q17 0.335 0.004 0.457q20 0.530 0.013 0.719q21 0.531 0.051 0.707Eigenvalue 2.850 1.763Proportion 0.203 0.125Cumulative 0.204 0.330a Correlations between items and principal components after Varimaxrotation.Numbers in bold indicate items with loadings > 0.32.The internal criterion index (Guttman’s eta)of the MCA scaling was equal to 0.285, and theCronbach’s alpha coefficient was 0.722, indicatingan ‘‘acceptable’’ optimal scaling.The MCA optimal weights are reported inTable 3 and displayed in Fig. 1. The transformationplot of the optimal weights shows thatall of the items describe a straight line (arein a linear form), and therefore, the Likertequidistance assumption was respected. Thus,the original Likert points from 1 to 5 were retainedfor the 10 selected items, and in theCFA phase the items were processed as continuousvariables. McDonald’s omega index wasequal to 0.708, indicating an acceptable reliability,and the SRMR index was equal to0.03, i.e., the assumption of conditional itemsindependence given the unidimensional instrumentwas supported.Raw item-total score correlations variedfrom 0.61 (q4) to 0.40 (q17) (Table 4). Thesame trend was found for the optimal itemtotalscore correlations (from 0.65 of q4 to0.36 of q17), and it was similar for item-factorcorrelations (from 0.58 of q10 to 0.23 of q17).This suggests that the sum row scores or the sumoptimal scores were good values of the ‘‘true’’scores of the continuous unidimensional factorunderlying the 10-item set called ‘‘pain knowledgeand attitudes’’ (PAK) that health care providersmight have toward patients.

732 Zanolin et al.Vol. 33 No. 6 June 2007Table 3MCA/HOMALS Optimal Weights of the Selected 10 Likert Items of the PAK Questionnaireq2 q3 q4 q8 q9 q10 q12 q17 q20 q211 0.93 0.80 1.21 0.84 1.43 1.04 1.32 0.78 0.83 1.322 0.40 0.30 0.60 0.27 0.57 0.50 0.59 0.28 0.60 0.563 0.24 0.25 0.11 0.16 0.13 0.24 0.20 0.21 0.02 0.054 0.37 0.73 0.66 0.31 0.59 0.66 0.21 0.31 0.50 0.415 1.13 1.67 1.68 1.30 1.39 1.45 0.95 1.22 1.58 1.81Mean 0 0 0 0 0 0 0 0 0 0Variance 0.31 0.28 0.42 0.15 0.38 0.38 0.26 0.13 0.27 0.28Description of the PAK Scale ScoresThe mean number of correct answers for theselected 10 items of the PAK scale was 4.0/10(40%; CI: 39.3%e40.6%); physicians had47.7% of correct answers and nurses 37.2%(P < 0.001). Anesthesiology and Emergencyscored 46.9%, followed by other departmentswith 42.1%, Medicine 39.8%, and Surgery38.0% (P < 0.001).When considering the PAK questionnaireon the standard scale from 0 (least favorableattitude) to 100 (most favorable attitude), thestandardized mean score (Table 5) calculatedon the whole sample was equal to 52.6% (CI:52.3%e53.0%). The difference between thepercentage score of physicians (56.5%) andnurses (51.3%) was statistically significant(P < 0.001), as was the difference between Anesthesiologyand Emergency (56.1%, the highestpercentage), and other departments(54.8%), Medicine (52.6%), and Surgery(51.6%; P < 0.001). Significant differences alsowere observed among northern, central (thehighest percentage), and southern Italy (thelowest). A significant interaction (P < 0.001)between hospital departments and professionalstaff was found (Table 5): There was a decreasein knowledge between physicians in Anesthesiologyand Emergency, followed by doctors inMedicine and then physicians in Surgery,whereas the knowledge of nurses remainedalmost constant.DiscussionThis study provides an overview of the professionalpreparation and attitudes of physiciansand nursing staff in Italy with regard topain. Moreover, through the data collected,a reliable and valid instrument to assess thepain knowledge of health professionals hasOptimal quantification2,01,51,00,50,0-0,5-1,0q2q3q4q8q9q10q12q17q20q21-1,5-2,01 2 3 4 5Likert pointsFig. 1. Transformation plots of the selected 10 Likert items of the PAK questionnaire.

Vol. 33 No. 6 June 2007 Questionnaire on Pain Knowledge733Table 4Raw and Optimal Item-Total Correlations, andItem-Factor Correlation of the Selected 10 LikertItems of the PAK QuestionnaireItemsRaw Item-TotalCorrelationOptimal Item-Total CorrelationItem-FactorCorrelationq2 0.572 0.555 0.457q3 0.518 0.530 0.431q4 0.608 0.647 0.572q8 0.415 0.382 0.274q9 0.585 0.618 0.563q10 0.596 0.620 0.577q12 0.516 0.507 0.442q17 0.401 0.355 0.227q20 0.505 0.517 0.423q21 0.509 0.534 0.431Reliability 0.703 0.722 0.708been developed. Participation in the study wason a voluntary basis. However, we believe thatthe high number of participants and the locationof the hospitals in different regions of thecountry make the results representative of theItalian situation. Furthermore, newly collecteddata from other hospitals in Italy (Zanolin,data not published), obtained by using thesame initial questionnaire, seem to be veryTable 5Mean (SD) of PAK Standard Score (Percentageof Maximum Knowledge) of Health CareProviders (n ¼ 4,961) by Hospital Location,Profession, and Hospital DepartmentProfession aPhysicians(n ¼ 1,348)Nurses(n ¼ 3,457) TotalHospital departmentsSurgery 53.0 (12.3) 51.0 (12.5) 51.6 (12.5)(n ¼ 1,931)Medicine 56.9 (12.9) 51.1 (11.6) 52.6 (12.4)(n ¼ 2,363)Anesthesiology 63.8 (13.0) 52.5 (13.3) 56.1 (14.1)(n ¼ 575)Other56.6 (14.0) 54.5 (11.5) 54.8 (12.5)departments(n ¼ 90)Hospital locationsNorthern Italy 56.5 (12.7) 51.9 (11.3) 53.1 (12.0)(n ¼ 2499)Central Italy 57.5 (13.3) 52.4 (12.1) 53.7 (12.6)(n ¼ 1880)Southern Italy(n ¼ 582)52.9 (14.1) 45.5 (14.2) 47.4 (14.6)Total (n ¼ 4,961) 56.5 (13.2) 51.3 (12.2) 52.6 (12.7)P < 0.001 for the differences in hospital departments, hospitallocations, and professional categories.P < 0.001 for the interaction between professional categories andhospital departments.a 156 cases of professional data missing.similar to the findings presented here. Thisconfirms that the findings of this study canbe generalized to fit most hospital healthprofessionals working in Italy.The Initial QuestionnaireThe overall percentage of correct answerswas 51.2%. This does not greatly differ fromthe results published by Lebovits et al., 6 whoconducted a study in three New York City hospitalsusing a 15-item questionnaire that wasvery similar to ours. Out of 686 nurses, physicians,pharmacists, and medical and nursingstudents, 56% correct answers were obtained.In a previous study, the authors found 61%correct answers in one single hospital in Italy, 9after administering a very similar 16-item questionnaireto hospital staff.After analyzing the answers to individualquestions, the highest percentages of correctanswers refer to the basic problems of interpretationand pain treatment: continuous symptomassessment (q13), individual differencesin expressing pain (q15), and administrationof drugs at fixed times (q1). However, the lowestpercentages refer to the misinterpretationof the placebo effect (q12) and mistaken beliefslinked to the danger of drug addiction(q19 and q21). These results are similar tothose obtained in the study conducted in a singlehospital in Italy, 9 although they are slightlylower. On one hand, they seem to indicate thatthere is considerable awareness toward a patientin pain, but on the other hand, there isan important lack of preparative training inthe case of pharmacological treatment.In the present study, there was a statisticallysignificant difference between percentages ofcorrect answers of the different professionalgroups (physicians 58.1% vs. nurses 48.7%).This difference was also noticed by Lebovitset al. 6 and Visentin et al. 9 and could be dueto the lack of adequate training programs fornurses. The difference in answers between professionalsworking in different specialist fieldsalso was significant from a statistical point ofview: Correct answers were more frequentamong staff from intensive care departmentsand medical wards compared to surgical departments(similar findings were reported byLebovits et al. 6 and Visentin et al. 9 ).The percentage of correct answers was significantlyhigher in central Italy with respect

734 Zanolin et al.Vol. 33 No. 6 June 2007to those obtained in the north and the south,which was probably due to the presence ofa higher number of small-sized hospitals takingpart in the survey. In these kinds of hospitals,the staff is usually less stressed by othercommitments and can dedicate more time topain management, which is not usually considereda priority. Moreover, sensitization to paincan easily reach a greater percentage of thehospital staff in smaller environments. Thelower percentage of correct responses inthe south of Italy is not surprising, as hospitalsin that part of the country are not commonlyconsidered at the same level as the rest ofthe country. Nevertheless, the total overall percentageof correct answers was low, revealingthe necessity to implement training coursesspecifically for the fields suggested by the questionswith the worst response rates.Psychometric AnalysisDuring the psychometric analysis, some questionswere excluded, as they were weakly correlatedwith the others, and q19, which was verysimilar to q4, was not included. The PCA outputrevealed that the initial questionnaire was notunidimensional, but it was made up of two components.Only the first one, ‘‘knowledge andattitudes toward the treatment of pain,’’accounting for the greatest explained total variance/pairwisecorrelations, was considered inthe MCA/CFA scaling assessment. Another reasonfor excluding the second component wasthat it only contained four questions witha high percentage of correct answers, and soit was not very useful for the aim of our study.A relatively good internal homogeneity wasfound for this set of 10 items after MCA scaling,as Guttman’s eta was equal to 0.285, whichis close to the 0.30 value that is considered thecut off for good homogeneity. Cronbach’s alphacoefficient was 0.72, denoting a good reliability,as it exceeded the value of 0.70 andindicated a low degree of error in measuringthe characteristic of interest. As far as the internalhomogeneity is concerned, most itemswere referred either to the medical knowledgeof analgesic use (q2, q3, q9, and q12) or toprejudice about presumed misuse (q4, q10,q20, and q21), whereas q8 and q17 dealt withpain assessment of health professionals withrespect to patient perception, which could perhapslead to a decrease in homogeneity.Questions 8 and 17 are less correlated to thetotal score than the other items (Table 3),which is probably due to the fact that thesetwo questions are slightly different from theothers, confirming their contribution to thedecrease in homogeneity. The MCA methodalso makes it possible to test the equidistanceacross the Likert points within each question.This was confirmed for all of the items, revealingthat there was no necessity to use optimalscaling scores.Finally, through CFA we could evaluate constructvalidity: The SRMR index was less than0.05, indicating that all of the items are linkedto a unique underlying factor (dimension),and, therefore, this scale presents very goodconstruct validity. McDonald’s omega confirmsthe acceptable reliability of the reduced questionnaire(PAK).The question with the best item-total andoptimal scoring-total correlation was q4, followedby q10, which was the best for itemfactorcorrelation. On the contrary, as alreadymentioned, the questions presenting a loweritem-total correlation were q17 and q8, probablydue to the slightly different contentorientation.The PAK Scale ScoresThe mean number of correct answers of the10-item PAK questionnaire was 10% lower withrespect to the initial questionnaire, becausemost of the items with the highest percentageof correct response had not been selected forthe final version. This is an important characteristicbecause questions having an excessivelyhigh percentage of correct answers do not discriminatesubjects with a good knowledge inrespect to the others. The other differences betweenthe categories of professional staff oramong hospital departments gave the sameresults as those obtained from the initialquestionnaire.The standardized score was higher than thecorrect answer percentage of the initial questionnaire,because it also assigned a score tothe ‘‘neither agree nor disagree’’ answers.The trend of the score differed according tophysicians (gradually increasing from Surgeryto Anesthesiology and Emergency) and nurses(almost constant across hospital departments)in different hospital departments, and the explanationfor this could be that there is no

Vol. 33 No. 6 June 2007 Questionnaire on Pain Knowledge735specialization in different medical disciplinesfor nurses in Italy at present. Consequently,nurses have all undergone the same professionaltraining in pain management, regardlessof the ward they work in. On thecontrary, physicians have different professionalbackgrounds, based on their specialization,which may comprise training in pain management(e.g., anesthesiologists) or not (e.g., surgeons).Moreover, surgeons usually developtheir technical abilities to a higher level and insteaddelegate the control of postoperativepain to anesthesiologists.The proposed PAK scale in this survey fillsa void in the validated instruments in the fieldof testing the general knowledge about paintreatment of hospital staff. It is brief and caneasily be administered to a considerable numberof people. Another advantage is the simpleway in which the PAK questionnaire quantifiesadherence to scientific criteria concerningpain knowledge on a scale from 0 (0% standardscore; the least favorable level of knowledge andattitude) to 40 (100% standard score; the mostfavorable level of knowledge and attitude). Nevertheless,the PAK does not assess other importantaspects of pain management that are morelinked to clinical practice, such as the complianceor the motivation in approaching theproblem of pain in a hospital setting. Hopefully,other surveys will be implemented to study indepth these important elements.AcknowledgmentsThe authors wish to acknowledge the followinghospitals and local coordinators participating inthe study: Alessandria (G. D’Amico), GarbagnateMilanese (F. Zucco), Feltre (G. Gobber), Mestre(G.P. Pinato), Rovigo (B. Piva), Latisana (U.Colonna), Castelnuovo né Monti (D.D. Murri),Lugo di Romagna (V. Ricci), Modena (B. Biasi),Empoli (R. Di Grancio), Grosseto (C. Casadio),Arezzo (P. Maurizi), Gubbio (T. Lazzarini), Narni(A. Favilli), Senigallia (F. Tardioli), ClinicaColumbus Rimini (G. Pari), Eboli (A. De Martino),Taranto (D. Semeraro), and Tricase (S.Colonna).References1. Donovan M, Dillon P, McGuire L. Incidenceand characteristics of pain in a sample of medicalsurgical inpatients. Pain 1987;30:69e78.2. Abbott FV, Gray-Donald K, Sewitch MJ, et al.The prevalence of pain in hospitalized patientsand its resolution over six months. Pain 1992;50:15e28.3. Trentin L, Visentin M, de Marco R, Zanolin E.Prevalence of pain in a public hospital: correlationbetween patients and caregivers. J Headache Pain2001;2:73e78.4. Costantini M, Viterbori P, Gaddo F. Prevalenceof pain in Italian hospital: results of regional crosssectionalsurvey. J Pain Symptom Manage 2002;23(3):221e230.5. Visentin M, Zanolin E, Trentin L, Sartori S, deMarco R. Prevalence and treatment of pain in adultsadmitted to Italian hospitals. Eur J Pain 2005;9:61e67.6. Lebovits AH, Florence I, Bathina R, et al. Painknowledge and attitudes of healthcare providers:practice characteristic differences. Clin J Pain1997;13:237e243.7. Levin ML, Berry JI, Leiter J. Management ofpain in terminally ill patients: physician reports ofknowledge, attitudes, and behavior. J Pain SymptomManage 1998;15:27e40.8. Drayer RA, Henderson J, Reidenberg M. Barriersto better pain control in hospitalized patients.J Pain Symptom Manage 1999;17:434e440.9. Visentin M, Trentin L, de Marco R, Zanolin E.Knowledge and attitudes of Italian medical staff towardsthe approach and treatment of patients inpain. J Pain Symptom Manage 2001;22:925e930.10. Ponte CD, Johnson-Tribino J. Attitudes andknowledge about pain: an assessment of West Virginiafamily practitioners. Fam Med 2005;37(7):477e480.11. Mercadante S, Salvaggio L. Cancer pain knowledgein Southern Italy: data from a postgraduaterefresher course. J Pain Symptom Manage 1999;11:108e115.12. Minotti V, Betti M. Attitudes of Italian generalpractitioners in the treatment of cancer pain.Tumori 1997;83:729e731.13. Porzio G, Aielli F, Narducci F, et al. Knowledgeand attitudes of Italian medical oncology residentstowards the approach and treatment of pain.J Pain Symptom Manage 2003;26(1):590e592.14. Broekmans S, Vanderschueren S, Morlion B,Kumar A, Evers G. Nurses’ attitudes toward paintreatment with opioids: a survey in a Belgian universityhospital. Int J Nur Stud 2004;41:183e189.15. Edwards HE, Nash RE, Najman JM, et al. Determinantsof nurses’ intention to administer opioidsfor pain relief. Nurs Health Sci 2001;3:149e159.16. Lai YH, Dalton JA, Belyea M, et al. Developmentand testing of the pain opioid analgesics beliefsscale in Taiwanese cancer patients. J Pain SymptomManage 2003;25:376e385.

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