a cross - sectional study was performed in 85 patients who were seen in a usual rheumatology outpatient clinic setting in daegu , korea , between may 2012 and july 2012 , and who received a diagnosis of as according to the modified new york criteria . the study was reviewed and approved by the ethical review board of the institute prior to its initiation , and written informed consent was received from every patient prior to enrollment . patients were excluded from the study if they were younger than 18 years and had another rheumatic disease in addition to as . each patient seen in the clinic , with any diagnosis , completed a korean version of mdhaq , which was translated and validated by lee et al . each patient with as also completed a basdai and basfi . an asdas and basmi were recorded by a health professional , either a metrologist or rheumatologist . rapid3 is scored on the mdhaq as the 0- to 30-point sum of three 0- to 10-point patient - reported measures : physical function , pain , and patient global estimate of status . other measures were scored as described in the literature ( but not included in this report ) . basdai includes 6 measures : fatigue , back pain , pain and swelling of peripheral joints , pain of enthesis , degree of morning stiffness , and duration of morning stiffness . basfi includes 10 queries concerning physical function , scored as integers from 1 (  easy  ) to 10 (  impossible  ) on a likert scale . asdas - esr ( erythrocyte sedimentation rate ) or asdas - crp ( c - reactive protein ) are calculated according to a formula that includes patient global status , spinal pain , spinal stiffness , fatigue , physical function , spinal mobility , and acute - phase reactant ( esr or crp ) . basmi includes 6 measures : occiput wall distance , modified schober test , lateral spinal flexion , chest expansion , cervical rotation , and intermalleolar distance . statistical analyses were performed using stata 12.1 for windows ( college station , tx ) . the shapiro - wilk w test was used to identify normality of distribution in the study population . wilcoxon rank - sum test and spearman correlations were computed for each individual measure and total scores in the composite indices , including deletion of pain scores from each index . patients were classified for disease activity / severity according to basdai ( 4 active vs < 4 inactive ) , asdas ( 1.3 active vs < 1.3 inactive ) , and rapid3 categories that have been developed for ra : more than 12 , high ; 6.1 to 12 , moderate ; 3.1 to 6 , low severity ( the term  severity  is used , as self - report scores do not necessarily distinguish activity from damage ) ; and 0 to 3 , remission . it is noted that these categories were developed in comparison to the disease activity score in 28 joints ( das28 ) for ra and have not been validated in as , although they may be applicable to other rheumatic diseases . cross tabulations ,  tests , and scatter plots were used to analyze statistical significance of possible associations between rapid3 , basdai , and asdas . a cross - sectional study was performed in 85 patients who were seen in a usual rheumatology outpatient clinic setting in daegu , korea , between may 2012 and july 2012 , and who received a diagnosis of as according to the modified new york criteria . the study was reviewed and approved by the ethical review board of the institute prior to its initiation , and written informed consent was received from every patient prior to enrollment . patients were excluded from the study if they were younger than 18 years and had another rheumatic disease in addition to as . each patient seen in the clinic , with any diagnosis , completed a korean version of mdhaq , which was translated and validated by lee et al . each patient with as also completed a basdai and basfi . an asdas and basmi were recorded by a health professional , either a metrologist or rheumatologist . rapid3 is scored on the mdhaq as the 0- to 30-point sum of three 0- to 10-point patient - reported measures : physical function , pain , and patient global estimate of status . other measures were scored as described in the literature ( but not included in this report ) . basdai includes 6 measures : fatigue , back pain , pain and swelling of peripheral joints , pain of enthesis , degree of morning stiffness , and duration of morning stiffness . basfi includes 10 queries concerning physical function , scored as integers from 1 (  easy  ) to 10 (  impossible  ) on a likert scale . asdas - esr ( erythrocyte sedimentation rate ) or asdas - crp ( c - reactive protein ) are calculated according to a formula that includes patient global status , spinal pain , spinal stiffness , fatigue , physical function , spinal mobility , and acute - phase reactant ( esr or crp ) . basmi includes 6 measures : occiput wall distance , modified schober test , lateral spinal flexion , chest expansion , cervical rotation , and intermalleolar distance . statistical analyses were performed using stata 12.1 for windows ( college station , tx ) . the shapiro - wilk w test was used to identify normality of distribution in the study population . wilcoxon rank - sum test and spearman correlations were computed for each individual measure and total scores in the composite indices , including deletion of pain scores from each index . patients were classified for disease activity / severity according to basdai ( 4 active vs < 4 inactive ) , asdas ( 1.3 active vs < 1.3 inactive ) , and rapid3 categories that have been developed for ra : more than 12 , high ; 6.1 to 12 , moderate ; 3.1 to 6 , low severity ( the term  severity  is used , as self - report scores do not necessarily distinguish activity from damage ) ; and 0 to 3 , remission . it is noted that these categories were developed in comparison to the disease activity score in 28 joints ( das28 ) for ra and have not been validated in as , although they may be applicable to other rheumatic diseases . cross tabulations ,  tests , and scatter plots were used to analyze statistical significance of possible associations between rapid3 , basdai , and asdas . median age was 38.7 years ; disease duration , 7.0 years ; body mass index , 23.8 kg / m ; level of formal education , 14.0 years ; and hla - b27 positivity , 94.1% ( table 1 ) . demographic and clinical characteristics of study patients rapid3 scores were correlated significantly with basdai (  = 0.82 , p < 0.001 ) , basfi (  = 0.66 , p < 0.001 ) , and asdas (  = 0.76 , p < 0.001 ) ( table 2 , fig . ) . these correlations were in the same range as correlations of basdai with asdas - esr (  = 0.81 ) and asdas - crp (  = 0.77 ) ( fig . ) . spearman correlations of rapid3 with as disease - specific composite and individual measures including basdai , asdas , and basfi correlation plots comparing scores for rapid3 versus ( a ) basdai , ( b ) asdas - esr , and ( c ) asdas - crp with rapid3 , and ( d ) scores for basdai versus asdas - esr . note high correlations of these measures , in the same range for rapid3 versus as indices as for basdai versus asdas . correlations of rapid3 were significant with individual responses on the basdai or basfi for spinal pain (  = 0.75 , p < 0.001 ) , spinal stiffness (  = 0.74 , p < 0.001 ) , fatigue (  = 0.68 , p < 0.001 ) , and physical function (  = 0.66 , p < 0.001 ) ( table 1 ) . correlations of rapid3 with physical measures of spinal mobility , or with acute - phase reactants esr and crp , were not statistically significant ( table 2 ) . overall , 20 , 25 , 23 , and 37 patients had rapid 3 scores indicating high , moderate , low severity , and remission , respectively , according to categories developed initially for ra . interrater agreement of rapid3 remission or not in remission with asdas inactive or active was significant (  = 0.486 , agreement = 77.8% , p < 0.001 ) , but low between rapid3 remission or not in remission and basdai inactive or active (  = 0.160 , agreement = 45.6% , p = 0.002 ) . however , all 20 patients with basdai scores of 4 or greater , indicating active as , had rapid3 scores of greater than 12 , indicating high severity ( table 3 ) . among 33 patients with asdas of greater than 1.3 , indicating active disease , 26 ( 79% ) had high severity according to rapid3 ( table 3 ) . the basdai , asdas , basfi , and basmi are standard disease - specific indices to assess the status of patients with as . these indices may include measures from patient self - report , a health professional , and laboratory tests and are collected feasibly in clinical trials and other clinical research , as well as in routine care at a few sites with a special interest in as . however , most routine clinical rheumatology care settings do not collect an index to assess ra quantitatively ; it appears unlikely that a site would collect a basdai in as patients when rapid3 is not collected in ra patients . it is difficult to collect several different patient questionnaires from patients with different diagnoses in busy clinical settings . furthermore , collection of several domains of asdas core data set measures and calculation of complex formulas for asdas are not feasible in all individual patients seen in routine care , despite an excellent web site for calculation ( http://www.asas-group.org/research/asdas_calculator/asdas.html ) . by contrast , it is rather simple for the clinic receptionist to distribute the same questionnaire to each patient upon registration at the clinic . this practice facilitates completion of the questionnaire by the patient in the waiting area and helps the patient prepare for the visit , so the information is available to both patient and rheumatologist at initiation of the encounter . scoring of rapid3 on an mdhaq requires 5 seconds , and rapid3 is useful in all rheumatic diseases in which it has been studied , including ra , systemic lupus erythematosus , psoriatic arthritis , gout , vasculitis , osteoarthritis , and as . rapid3 is feasible in assessing disease severity and improvement in routine clinical of ra and is similar to das28 and clinical disease activity index ( cdai ) to distinguish active from control treatments in ra trials of adalimumab , abatacept , and certolizumab . the limited feasibility of collecting basdai and asdas as 1 of several questionnaires in routine care usually leaves laboratory tests as the only quantitative data available for clinical decisions in the medical records of most patients with as . however , laboratory tests often are not available at the time of the encounter and often are normal in patients with active clinical disease . thus , improvement ( or worsening ) in as patients is characterized only by narrative descriptions , rather than by quantitative clinical data . first , it is cross sectional ; longitudinal studies extending a recently published small series including as over a short period would be desirable in clinical trials and usual care . second , low  s between rapid3 and basdai , although statistically significant , were not as strong as might be ideal , explained in part by the presence of joint damage and/or concomitant fibromyalgia in patients who do not have active disease on physical examination . this phenomenon has been documented to be a significant issue with das28 and cdai in ra , in which patients with scores indicating moderate or severe activity did not have intensification of therapy , explained in large part by joint damage and fibromyalgia . in our study , all 21 patients with basdai of 4 or greater , indicating active disease , had rapid3 of greater than 12 , indicating high severity . rapid3 is thus effective to provide the most important goal of recognizing patients with severe disease activity who may require intensification of treatment , particularly in the era of anti tumor necrosis factor agents , although some of these patients may not require aggressive anti - inflammatory therapy . a third possible limitation is that rapid3 was not correlated significantly with metrology scores or laboratory tests . however , low correlations of patient indices with laboratory tests and imaging data are seen in ra . for example , a cdai is as effective to document changes in status as a simplified disease activity index , which includes an esr or crp . of course , as - specific spinal flexibility measures are informative in clinical trials and other research and valuable in development of improved treatments , but may not be required in usual care . a fourth possible limitation is that highly significant correlations do not necessarily imply identity of information contained in 2 measures , as a line indicating near identity may not go through the origin at zero , but be shifted upward or downward . a shift upward is seen for correlations of rapid3 ( as well as basdai ) with asdas scores . furthermore , correlations of  = 0.8 are at a level seen in test - retest studies of the same measure , as high as seen in clinical medicine . similar high correlations have been observed in 3 other settings in the united states , turkey , and norway , indicating great similarity of the information provided by the 2 questionnaires . the authors do not advocate at all that rapid3 should replace basdai , basfi , asdas , or basmi . furthermore , rapid3 ( or any index ) must be supplemented by a standard medical history , physical examination , laboratory tests , and/or any other clinical information regarded as important by the rheumatologist in formulating clinical decisions . collection of rapid3 in no way precludes collection of basdai , asdas , or any other index . nonetheless , rapid3 is feasible in usual care and appears preferable to the absence of any quantitative clinical measure at all , as is the case for most as patients seen by rheumatologists at this time . the mdhaq / rapid3 might be added to research protocols to provide information to facilitate quantitative clinical assessment in routine care of patients with as .
backgrounddisease - specific ankylosing spondylitis ( as ) indices , including basdai ( bath as disease activity index ) , basfi ( bath as functional index ) , asdas ( as disease activity score ) , and basmi ( bath as metrology index ) , are widely used in clinical trials and in some clinical settings , but not in most routine care . 
 laboratory tests usually are the only quantitative measures included in routine care of as patients , but often are poorly informative . 
 routine assessment of patient index data 3 ( rapid3 ) on a multidimensional health assessment questionnaire ( mdhaq ) is feasible and informative in many rheumatic diseases.objectivethe aim of this study was to compare rapid3 to basdai , basfi , asdas , and basmi in a cross - sectional analysis of 85 korean as patients collected in routine care.methodsmdhaq/rapid3 , basdai , and basfi were completed by patients , and asdas and basmi assessed by health professionals . indices and individual measures were compared using correlations , cross tabulations , scatter plots , and  statistics.resultsrapid3 scores were correlated significantly with basdai (  = 0.82 ) and asdas - esr ( erythrocyte sedimentation rate ) (  = 0.76 ) , at levels similar to the correlation of basdai with asdas - esr (  = 0.81 ) . 
 all 21 patients with basdai scores of 4 or greater , indicating active as , were among 39 patients who had rapid3 scores of greater than 12 , indicating high severity , whereas 79% of 33 patients with asdas of greater than 1.3 , indicating high activity , had rapid3 high severity.conclusionsrapid3 gives similar information to basdai and asdas in as patients , in this limited cross - sectional study from 1 setting . 
 ankylosing spondylitis 
 specific measures are needed for clinical trials , but poorly feasible in most busy clinical settings . 
 the mdhaq / rapid3 offers pragmatic quantitative clinical assessment of as patients in routine care .