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Diagnosis of Fibromyalgia Syndrome—A Comparison of Association of the Medical Scientific Societies in Germany, Survey, and American College of Rheumatology Criteria Winfried Ha¨user, MD,*w Sebastian Hayo,* Werner Biewer, MD,z Mechthild Gesmann, MD,y Hedi Ku¨hn-Becker, MD,J Frank Petzke, MD,z Hubertus von Wilmoswky, MD,# Objectives: The survey and the Association of the Medical Scientific Although not developed as a diagnostic tool, the American College criteria (ACR) for the classification Societies in Germany (AWMF) criteria had been developed to of fibromyalgia syndrome (FMS), namely the presence overcome problems associated with tender point criterion of the of chronic widespread pain (CWP) and at least 11 of 18 American College of Rheumatology (ACR) (lacking validation painful tender points (TP) on manual pressure,1 have for clinical diagnosis, inconsistent use by rheumatologists, and become the de facto diagnostic criteria used for basic nonrheumatologists) for the clinical diagnosis of fibromyalgiasyndrome (FMS). We compared the concordance between these research and clinical studies on FMS.2 A major problem with the TP criterion for the definition of FMS is its biastoward the selection of females and individuals with high Methods: Consecutive patients of different clinical settings referred levels of physical and psychologic distress,3,4 out of the for the evaluation of chronic widespread pain or management 10 –26% of persons with CWP in the general population.5 of established FMS diagnosis were assessed by medical history, There is general agreement between medical disciplines a complete physical examination including tender points, andquestionnaires [self-constructed symptoms questionnaire, regional that the symptom of ‘‘chronic widespread pain (CWP)’’, as pain scale (RPS), Patient Health Questionnaire (PHQ 9 and 15)].
defined by the ACR (axial plus upper and lower body plus FMS according to AWMF-criteria was diagnosed by the history of left-sided and right-sided pain)1 or by epidemiologic criteria widespread pain (axial and all 4 extremities), the symptoms sleep (pain in the axial skeleton and all 4 extremities),5 is essential disturbances, fatigue, and feeling of swelling or stiffness of the for the clinical diagnosis of FMS. If other symptoms such hands or feet or face (Numeric rating scale Z1/10 each symptom) as fatigue and nonrestorative sleep or physical findings such and the exclusion of somatic diseases sufficiently explaining the as tenderness on pressure on at least 11/18 tender points symptoms. FMS according to survey criteria was diagnosed by should be used as adjuncts for the clinical diagnosis of FMS regional pain scale score Z8 and fatigue score Z6/10 on a visual is under debate. Wolfe claimed that clinicians should stop using TP examination (TPE) for the clinical diagnosis Results: Out of 310 patients, 292 could be analysed. AWMF and of FMS.6 In contrast Harth and Nielson concluded from a ACR were concordant in 86.6%, AWMF and survey criteria were narrative review of the literature that TPE is useful in the concordant in 78.8% and survey and ACR-criteria were con- Alternative tools for the clinical diagnosis of FMS had Discussion: AWMF, survey, and ACR criteria were moderately been suggested. Katz et al2 and Wolfe8 made the clinical concordant. As AWMF and survey criteria do not require tender diagnosis of FMS by clinician’s experience considering point examination, these criteria can be used by nonrheumatol- clinical criteria such as pain, fatigue, sleep disturbance, ogists for the clinical diagnosis of FMS.
comorbidity, and psychosocial variables without specifyingthe rules of diagnosis. Wolfe developed a questionnaire, Key Words: fibromyalgia syndrome, diagnosis, American College named the Regional Pain Scale (RPS) that assesses 19 of rheumatology, Association of the Medical Scientific Societies in articular and nonarticular body regions for the presence of pain. He suggested survey criteria characterized by the combination of at least 8/19 painful body areas on the RPSand a score of Z6 on an 11 point visual analogue scalefor fatigue. This approach correctly identified most patients Received for publication September 23, 2009; revised January 20, 2010; diagnosed with FMS by their rheumatologists based on the From the *Department of Internal Medicine I, Klinikum Saarbru¨cken clinical criteria mentioned above.8 Within 1 rheumatologic gGmbH, Winterberg 1; zRheumatological Practice, Saarbru¨cken; practice the concordance rates of the ACR, survey, and wDepartment of Psychosomatic Medicine, Technische Universita¨t clinical criteria of FMS were between 72% to 75%.2 These Mu¨nchen, Mu¨nchen; zDepartment of Anesthesiology and Post-operative Intensive Care Medicine, University of Cologne, Cologne; data have not been replicated in other settings.
#Department of Rheumatology, Knappschaftskrankenhaus Pu¨ttlin- Coordinated by the Association of the Medical gen, Pu¨ttlingen; **Department of Internal Medicine V, (Comple- Scientific Societies in Germany (AWMF) and the German mentary and Integrative Medicine), University of Duisburg-Essen,Kliniken Essen-Mitte, Germany; yPsychosomatic Medicine Prac- Interdiscplinary Association for Pain Therapy, 10 German tice, Herford; and JPain Medicine Practice, Zweibru¨cken.
medical and psychologcial scientific societies (general med- Reprints: Winfried Ha¨user, MD, Klinikum Saarbru¨cken gGmbH, icine, rheumatology, pain medicine, orthopaedic surgery, Winterberg 1, D-66119 Saarbru¨cken, Germany (e-mail: whaeuser@ psychiatry, psychosomatic medicine, neurology, psychology), Copyright r 2010 by Lippincott Williams & Wilkins and 2 self-help organisation developed an evidence-based Clin J Pain  Volume 26, Number 6, July/August 2010 Clin J Pain  Volume 26, Number 6, July/August 2010 and consensus-based guideline on the classification, diag- nosis, and therapy of FMS.9 The guideline classified FMS If patients reported a diagnosis of FMS or if FMS was as a functional somatic syndrome.10 Thus, the clinical suspected by medical history and/or pain drawings, patients diagnosis should be based on symptoms and the exclusion were asked to complete these questionnaires: A self- of somatic diseases which sufficiently explain CWP by constructed sociodemographic and medical questionnaire carrying out a complete clinical examination and defined assessing age, sex, duration of CWP and FMS-diagnosis, routine blood tests.9 On the basis of studies on the main partnership and professional status and the symptoms sleep symptoms of FMS-patients in different clinical settings,11–13 disturbances, mental and physical fatigue, feeling of these additional symptoms besides CWP are required for swelling or stiffness of the hands, feet, and legs on an 11 the clinical diagnosis of FMS: sleep disturbances and point a numeric rating scale; the RPS8, and the Patient mental or physical fatigue and feeling of swelling or Health Questionnaire PHQ 9 and 15.15,16 The PHQ is a stiffness of the hands or feet or legs. These criteria were self-administered version of the Primary Care Evaluation supported by the consensus committee, but have not been of Mental Disorders diagnostic instrument for common validated in epidemiologic or clinical studies.
mental disorders. To assess somatic symptoms and The aim of this study was to compare the concordance depressed mood, the respective parts of the validated of the 3 diagnostic criteria in different clinical settings to German version of the PHQ were used.17 The PHQ-15 overcome potential selection and investigator bias. Further- comprises 13 somatic symptoms from the PHQ, each more, we assessed if the different diagnostic criteria would symptom scored from 0 (‘‘not bothered at all’’) to 2 lead to different sociodemographic and clinical profiles of (‘‘bothered a lot’’). PHQ-15 scores of 5,10,15 represent cutoff points for low, medium, and high somatic symptomseverity, respectively. The usefulness of the PHQ-15 inscreening for somatisation and in monitoring somatic symptom severity in clinical practice and research had been shown in numerous studies.16 The PHQ-9 is the depressionmodule of the PHQ, which scores each of the 9 DSM-IV The study was carried out in 1 rheumatologic practice criteria as ‘‘0’’ (not at all) to ‘‘3’’ (nearly every day). Validity (WB), 1 outpatient department of rheumatology of a has been assessed against an independent structured mental district hospital (SH supervised by HvW), 1 pain medicine health professional interview. PHQ-9 scores of 0 to 4 practice (HKB), 1 university pain clinic (FP), 1 psychoso- indicate no depression, 5 to 9 mild depression, 10 to 14 matic medicine practice (MG), 1 psychosomatic medicine moderate depression, 15 to 19 moderately severe depres- universitarian outpatient department (WH), and 1 depart- sion, and 20 to 27 severe depression.15 As items of the PHQ ment of integrative medicine of an academic teaching 9 and 15 comprise key symptoms of FMS, namely pain, hospital (JL). SH was a junior physician who was trained sleep disturbances, and fatigue, we calculated modified sum for this project for his doctoral thesis. The other investi- scores of these questionnaires by removing the items c gators were experienced clinicians who were working with (sleep problems), d (lack of energy), and g (trouble FMS-patients for at least 10 years. The patients underwent concentrating) from the PHQ 9 and the items b (back a complete physical assessment by these researchers. The pain) and c (pain in extremities) from the PHQ 15. Item d investigators had been instructed to carry out TPE (menstrual cramps or other problems with periods) was according to the manual tender point survey protocol.14 Consecutive patients referred to the settings detailed The concordance of the 3 different diagnostic criteria above for the evaluation and/or management of CWP, with was calculated by the percentage of the sum of positive and and without established diagnosis of FMS, were included negative agreements between 2 pairs of diagnostic criteria during the period of January to June 2009. Patients with each. Up to 25% of missing items in the PHQ 9 and 15 were somatic diseases, for example active inflammatory rheu- substituted by the individual median. If more than 25% matic disease, sufficiently explaining CWP, diagnosed by items were missing, the questionnaire was excluded from clinical examination, and laboratory testing, were excluded.
analysis. Missing items in the RPS and symptom ques- Patients with inactive somatic diseases, for example inflammatory rheumatic disease in remission not explaining To assess differences between groups, we compared mean scores of continuous demographic and clinical Diagnoses of FMS were made according to the ACR variables by analyses of variance (ANOVAS) with posthoc (CWP as defined by the ACR and tenderness on pressure of 2 group comparisons by the Dunnett-T3 test. w2 analysis at least 11/18 TP), survey (RPS score Z8/19 and fatigue was used for categorical variables. All tests were 2-tailed, score Z6/10 on a visual analogue scale in the last week), with the a-value set at 0.01 because of multiple compar- and AWMF-criteria (CWP defined as axial pain and pain in isons. All analyses were conducted with SPSS Version 17.0 all 4 extremities assessed by medical history and/or pain drawing and the report of sleep disturbances and fatigueand feeling of swelling or stiffness of the hands or feet orface in the last 3 mo with a score scale Z1/10 on a numeric rating scale on a self-constructed symptom questionnaire).
One of 311 patients approached refused to take part All patients gave their informed consent to data in the study. Three hundred ten patients participated. Of collection and analysis. The study was approved by the these, 16 patients were excluded because no complete data respective regional and institutional ethics committees if set of the 3 diagnostic criteria were available. Furthermore, 2 patients who reported to be diagnosed with FMS were Clin J Pain  Volume 26, Number 6, July/August 2010 excluded because they did not meet any of the 3 diagnostic were owing to a TP count <11. Twenty-nine percent ACR- criteria. Thus, 292 patients were included into analysis. In negative cases did not meet the ACR-criterion of CWP.
81/292 (27.7%) of the patients FMS was diagnosed for the AWMF and ACR were concordant in 86.6% (range first time. The sex ratio of the patients, the low educational 77.1 to 100), AWMF and survey criteria were concordant in level, the high levels of work disability, and physical and 78.8% (range 66.7 to 90.2), and survey and ACR-criteria somatic distress of most of the patients of the study sample were concordant in 79.5% (69.2 to 86.9) of the cases.
are consistent with known characteristics of FMS-patients There were no significant overall differences in the concor- in clinical settings and studies2 (Table 1). Yet, it is dances of the 3 diagnostic criteria between the study centers important to note that FMS was diagnosed also in a (Table 2). There were no significant differences of the minority of highly educated patients and in patients with concordances of the 3 diagnostic criteria between patients low levels of reported additional somatic and psychologic with initial and established diagnosis of FMS (Table 3).
distress. Only few significant differences of sociodemo- Patients who were positive in all 3 diagnostic criteria graphic and clinical characteristics of the patients were reported higher levels of depressed mood and somatic found between the study centers. The outpatient psycho- symptom severity than patients positive only in AWMF somatic department recruited more male patients than the other study centers. The percentage of patients with a higheducational level was larger in the department of integrative medicine than in the other study centers (details notreported).
The intercorrelationships of the 3 diagnostic groups Alternative criteria for the clinical diagnosis of FMS are shown graphically in Figure 1. Seventy-one percent of had been developed, to overcome problems associated with the patients were diagnosed with FMS by all 3 methods.
the use of the tender point criterion of the ACR for the Isolated positive cases were noted (1.4%, 3.1%, and 2.0% clinical diagnosis, and to offer nonrheumatologists alter- respectively, diagnosed by AWMF only, by survey only, natives of diagnosing FMS without TPE. These alternative and by ACR criteria only). AWMF negative cases were all criteria are the survey criteria and the criteria of the owing to lacking CWP defined as pain axially and in all Association of the Medical Scientific Societies in Germany.
4 extremities. Survey negative cases were all owing to a We compared the concordance of these 3 criteria in fatigue score <6. A majority of ACR negative cases (71%) different clinical settings in patients referred for the TABLE 1. Sociodemographic and Clinical Characteristics of the Total Study Sample (N=292) PHQ 15 somatic symptom severity score (0-26) PHQ 15 somatic symptom severity score modified (0-22) PHQ indicates patient health questionnaire; RPS, regional pain scale.
Clin J Pain  Volume 26, Number 6, July/August 2010 Why Are Alternative Criteria for the ClinicalDiagnosis of FMS Required? There are several practical and scientific reasons to develop alternative criteria for the clinical diagnosis of a. A standardized manual tender point survey is avail- able,14 but this protocol is not used in rheumatologic practice and in most clinical studies on FMS. Even with the standardization of manual TPE, there is the risk of ‘‘the harder you press (the more you believe?), the more b. The reliability and validity of the TP examination outside the context of FMS-specialized rheumatologic c. FMS is not a disease exclusively diagnosed and treated by rheumatologists. Patients are also diagnosed and treated by general practitioners, pain physicians, or psychiatrists.18–21 TPE is largely ignored in these settings. Nonrheumatologists, had not been trainedfor TPE within their residency program. Moreover,TPE would be time consuming in these settings. Even FIGURE 1. Venn diagram showing the intercorrelationship of if a competent physician of whatever discipline who the Association of the Medical Scientific Societies in Germany is able to conduct a thorough medical examination (AWMF) criteria, Survey criteria, and American College of could be taught a standardized manual TPE, the time to carry out this examination could be used to extracta more comprehensive psychosocial history. There-fore, the development of alternative diagnostic criteria evaluation of CWP or management of established FMS.
without TPE had been demanded by these medical We found moderate concordance between the 3 diagnostic criteria within this data set of FMS patients. We found d. Although increased tenderness or hyperalgesia/allo- no significant differences of concordance between the 3 dynia to pressure stimuli had been replicated by other diagnostic criteria comparing patients with initial diagnosis more objective ways of assessment,4,22 its relevance of FMS and patients with established FMS. The con- and specificity for the diagnosis of FMS had been cordances of diagnoses did not differ between the different settings. Patient’s positive by all 3 diagnostic criteriareported higher levels of distress than patients positive onlyby AWMF and ACR criteria.
Differences Between the DiagnosticCriteria of FMS Available There are some differences between the suggested alternatives to the ACR criteria for clinical diagnosis. The Katz et al reported a concordance of survey and ACR survey criteria had been developed on patients with FMS, criteria of 72.3%,2 which was comparable with the 1 in our rheumatoid arthritis (RA), and osteoarthritis (OA) in a study with 79.3% (range 71.4 to 86.7). The concordance rheumatologic practice setting. The items were selected to of the 3 diagnostic criteria in our study was higher than achieve a maximum discrimination between patients with between the 3 diagnostic criteria in the study of Katz et al FMS against patients with RA and OA. However, 29% of the patients with RA and 33% of the patients with OA also TABLE 2. Overall Agreement Between the 3 Different Criteria for the Diagnosis of Fibromyalgia Syndrome in Different Settings Department of Complementary Medicine N=60 *P<0.05; Not significant because of adjusted P value of multiple comparisons.
ACR indicates American College of Rheumatology; AWMF, Association of the Medical Scientific Societies in Germany; n.s., not significant; RPS, regional Clin J Pain  Volume 26, Number 6, July/August 2010 TABLE 3. Comparison of Concordances of 3 Different Diagnostic Criteria of Fibromyalgia Syndrome, Stratified to Patients With InitialDiagnosis, and Established Diagnosis of Fibromyalgia Syndrome fulfilled the survey criteria of FMS.1 Katz et al claimed expert consensus for the clinical diagnosis. The choice that the survey method has the advantage that it does not of symptoms was not determined by the intention to require an additional physical examination.2 discriminate FMS from other diseases by these symptoms.
The AWMF criteria had been suggested by a struc- The main symptoms of FMS, namely musculoskeletal pain, tured consensus of an interdisciplinary panel of experts of fatigue, and sleep disturbances, are also prevalent in the all medical and psychologic disciplines engaged in the care general population and in other somatic diseases and in of FMS patients and of representatives of FMS-patients.8 depressive disorder-although FMS patients can be clearly The most frequent symptoms reported by FMS-patients in differentiated from depressive disorders by the intensity of different settings (>98% of the patients)11,12 were chosen by reported pain and fatigue.13 The separation of FMS from TABLE 4. Comparison of Demographic and Clinical Characteristics of Patients With Different Concordances of 3 Different DiagnosticCriteria of Fibromyalgia Syndrome *P<0.05 Not significant because of adjusted P value of multiple comparisons.
**P<0.01.
***P<0.001.
Clin J Pain  Volume 26, Number 6, July/August 2010 somatic diseases sufficiently explaining CWP is carried out syndromes too, for example the Manning and Rome I, II, by medical history, complete physical examination, and and III criteria for irritable bowel syndrome.30 laboratory tests.9 Thus, even if the AWMF criteria do not Until a better clinical case definition of FMS exists, require TPE, a physical examination is indispensable for the all diagnostic criteria should be interpreted with caution initial diagnosis of FMS. The time required to exclude other and subject to modification.29 The ACR criteria seem to be medical causes of CWP is longer than TPE.
indispensable for clinical studies. The mean TP count of The exclusion of somatic diseases sufficiently explain- 9 to 10 in our ACR-negative cases suggests that a lower TP ing CWP is not required by the survey and ACR criteria, count criterion than 11 might be appropriate for the clinical but by the AWMF criteria and a Canadian expert diagnosis of FMS by the ACR-criteria. Katz et al found consensus on FMS.24 The exclusion of somatic diseases that a TP count discriminated maximally at a count Z6 for sufficiently explaining the symptoms is required for the diagnosis of functional somatic syndromes (eg, irritable AWMF and survey diagnoses do not require TPE bowel syndrome) in other medical disciplines too.10 More- which is 1 of the major obstacles for the diagnosis of FMS over, the evidence of the efficacy of pharmacologic in nonrheumatologic settings. Thus, AWMF and survey treatment of FMS is based on randomised controlled trials criteria can replace the ACR-criteria for clinical diagnosis that excluded patients with somatic diseases as potential of FMS in nonrheumatologic settings. Studies comparing the preference and applicability of the AWMF and surveycriteria by nonrheumatologists at all levels of care are necessary to find out if these diagnostic tools meet the needs of nonrheumatologists and possess reasonable sensitivity Patients with moderate and high levels of somatic and specificity. In case the AWMF-criteria will be accepted and psychologic distress were diagnosed irrespectively of by nonrheumatologists, studies should be conducted if the criteria used in our study. We found some socio- FMS will be diagnosed earlier by nonrheumatologists and demographic and clinical differences in cases of lacking if management and outcome of FMS will improve.
concordance. Our study showed that the AWMF criterialed more frequently to a diagnosis of FMS in men thanthe ACR-criteria. This finding is in line with the results ofepidemiologic studies. The ACR—criteria are associated with a sex ratio (women to men) of 6 to 8:1 in epidemiologic 1. Wolfe F, Smythe HA, Yunus MB, et al. The American College and clinical studies. Leaving the TP-criterion leads to of Rheumatology 1990 criteria for the classification of a more balanced sex ratio.3 Branco et al reported an fibromyalgia. Report of the multicenter criteria committee.
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