The Oswestry Disability Index, the Roland-Morris Disability Questionnaire, and the Quebec Back Pain Disability Scale: Translation and Validation Studies of the Iranian Versions Minimum clinically important difference in lumbar spine surgery patients: a choice of methods using the Oswestry Disability Index, Medical Outcomes Study questionnaire Short Form 36, and pain scales. Outcome scores in spinal surgery quantified: excellent, good, fair and poor in terms of patient-completed tools Outcome measures in chronic low back pain Comparison of the SF6D, the EQ5D, and the oswestry disability index in patients with chronic low back pain and degenerative disc disease Concurrent Comparison of Responsiveness in Pain and Functional Status Measurements Used for Patients With Low Back Pain Testing minimal clinically important difference: consensus or conundrum? Long-term results of surgery for lumbar spinal stenosis: a randomised controlled trial The efficacy of lumbar traction in the management of patients with low back pain Is a Condition-Specific Instrument for Patients with Low Back Pain/Leg Symptoms Really Necessary?: The Responsiveness of the Oswestry Disability Index, MODEMS, and the SF-36 Oswestry Disability Index is a better indicator of lumbar motion than the Visual Analogue Scale. What is an acceptable outcome of treatment before it begins? Methodological considerations and implications for patients with chronic low back pain PROMIS PF CAT Outperforms the ODI and SF-36 Physical Function Domain in Spine Patients Determining the quality and effectiveness of surgical spine care: patient satisfaction is not a valid proxy. The Reliability of the Shuttle Walking Test, the Swiss Spinal Stenosis Questionnaire, the Oxford Spinal Stenosis Score, and the Oswestry Disability Index in the Assessment of Patients With Lumbar Spinal Stenosis Predictive factors for successful clinical outcome 1 year after an intensive combined physical and psychological programme for chronic low back pain Association of catechol-O-methyltransferase genetic variants with outcome in patients undergoing surgical treatment for lumbar degenerative disc disease. Prospective analysis of clinical evaluation and self-assessment by patients after decompression surgery for degenerative lumbar canal stenosis. Development and Application of a Newly Designed Massage Instrument for Deep Cross-Friction Massage in Chronic Non-Specific Low Back Pain The MRC Spine Stabilization Trial: Surgical Methods, Outcomes, Costs, and Complications of Surgical Stabilization Comparison of spinal fusion and nonoperative treatment in patients with chronic low back pain: long-term follow-up of three randomized controlled trials. BACK PAIN AND DISABILITY AFTER LUMBAR LAMINECTOMY: IS THERE A RELATIONSHIP TO MUSCLE RETRACTION? The effect of duration of symptoms on standard outcome measures in the surgical treatment of spinal stenosis
Study Design . Cross-cultural translation and psychometric testing were performed . Objectives . To cross-culturally translate the Oswestry Disability Index ( ODI ) , Rol and -Morris Disability Question naire ( RDQ ) , and Quebec Back Pain Disability Scale ( QDS ) into Persian , and then investigate the psychometric properties of the Persian versions produced . Summary of Background Data . To the authors ’ knowledge , there is no vali date d instrument to measure functional status in Persian-speaking patients with low back pain ( LBP ) in Iran . To our knowledge , the widely used back-specific measures , the ODI , RDQ , and QDS , have not been translated and vali date d for Persian-speaking patients with LBP . Methods . The translation and cross-cultural adaptation of the original question naires were performed in accordance with published guidelines . A total of 100 patients with chronic LBP were asked to complete a question naire booklet ( the Persian versions of the ODI , RDQ , QDS , Short Form Health Survey ( SF-36 ) , and visual analog scale measure of pain ) . There were 31 r and omly select patients with chronic LBP asked to complete the second question naire booklet 24 hours later . Results . The Cronbach-α for the ODI , RDQ , and QDS was 0.75 , 0.83 , and 0.92 , respectively . The ODI , RDQ , and QDS showed excellent test-retest reliability ( intraclass correlation coefficient = 0.91 , 0.86 , and 0.86 , respectively ) ( P < 0.01 ) . The correlation among the ODI , RDQ , QDS and physical functioning scales of the SF-36 was −0.66 , −0.62 , and −0.69 , respectively ( P < 0.001 ) . The correlation among the ODI , RDQ , and QDS and visual analog scale was 0.54 , 0.36 , and 0.46 , respectively ( P < 0.001 ) . Conclusions . The Persian versions of the ODI , RDQ , and QDS are reliable and valid instruments to measure functional status in Persian-speaking patients with LBP.They are simple and fast scales , and the use of them can be recommended in a clinical setting and future outcome studies in Iran BACKGROUND CONTEXT The impact of  lumbar spinal surgery  is commonly evaluated with three patient-reported outcome measures : Oswestry Disability Index ( ODI ) , the physical component summary ( PCS ) of the Short Form of the Medical Outcomes Study ( SF-36 ) , and pain scales . A minimum clinical ly important difference ( MCID ) is a threshold used to measure the effect of clinical treatments . Variable threshold values have been proposed as MCID for those instruments despite a lack of agreement on the optimal MCID calculation method . PURPOSE This study has three purpose s. First , to illustrate the range of values obtained by common anchor-based and distribution-based methods to calculate MCID . Second , to determine a statistically sound and clinical ly meaningful MCID for ODI , PCS , back pain scale , and leg pain scale in lumbar spine surgery patients . Third , to compare the discriminative ability of two anchors : a global health assessment and a rating of satisfaction with the results of the surgery . STUDY DESIGN This study is a review of prospect ively collected patient-reported outcomes data . PATIENT SAMPLE A total of 454 patients from a large data base of surgeries performed by the Lumbar Spine Study Group with a 1-year follow-up on either ODI or PCS were included in the study . OUTCOME MEASURES Preoperative and 1-year postoperative scores for ODI , PCS , back pain scale , leg pain scale , health transition item ( HTI ) of the SF-36 , and Satisfaction with Results scales . METHODS ODI , SF-36 , and pain scales were administered before and 1 year after spinal surgery . Several c and i date MCID calculation methods were applied to the data and the result ing values were compared . The HTI of the SF-36 was used as the anchor and compared with a second anchor ( Satisfaction with Results scale ) . RESULTS Potential MCID calculations yielded a range of values : fivefold for ODI , PCS , and leg pain , 10-fold for back pain . Threshold values obtained with the two anchors were very similar . CONCLUSIONS The minimum detectable change ( MDC ) appears as a statistically and clinical ly appropriate MCID value . MCID values in this sample were 12.8 points for ODI , 4.9 points for PCS , 1.2 points for back pain , and 1.6 points for leg pain Outcome scores are very useful tools in the field of spinal surgery as they allow us to assess a patient ’s progress and the effect of various treatments . The clinical importance of a score change is not so clear . Although previous studies have looked at the minimum clinical ly important score change , the degree of score change varies considerably . Our study is a prospect i ve cohort study of 193 patients undergoing discectomy , decompression and fusion procedures with minimum 2-year follow-up . We have used three st and ard outcome measures in common usage , the oswestry disability index ( ODI ) , the  low back outcome score ( LBOS ) and the visual analogue score ( VAS ) . We have defined each of these scores according to a global measure of outcome grade d by the patient as excellent , good , fair or poor . We have also grade d patient perception and classified excellent and good as success and fair and poor as failure . Our results suggest that a median 24-point change in the ODI equates with a good outcome or is the minimum change needed for success . We have also found that different surgical disorders have very different minimal clinical ly important differences as perceived by patient perception . We found that for a discectomy a minimum 27-point change in the ODI would be classed as a success , for a decompression the change in ODI needed to class it as a success would be 16 points , whereas for a fusion the change in the ODI would be only 13 points . We believe that patient-rated global measures of outcome are of value and we have quantified them in terms of the st and ard outcome measures used in spinal surgery The purpose of this prospect i ve , single site cohort quasi-experimental study was to determine the responsiveness of the numerical rating scale ( NRS ) , Rol and –Morris disability question naire ( RMDQ ) , Oswestry disability index ( ODI ) , pain self-efficacy question naire ( PSEQ ) and the patient-specific functional scale ( PSFS ) in order to determine which would best measure clinical ly meaningful change in a chronic low back pain ( LBP ) population . Several patient-based outcome instruments are currently used to measure treatment effect in the chronic LBP population . However , there is a lack of consensus on what constitutes a “ successful ” outcome , how an important improvement/deterioration has been defined and which outcome measure(s ) best captures the effectiveness of therapeutic interventions for the chronic LBP population . Sixty-three consecutive patients with chronic LBP referred to a back exercise and education class participated in this study ; 48 of the 63 patients had complete data . Five question naires were administered initially and after the 5-week back class intervention . Also at 5 weeks , patients completed a global impression of change as a reflection of meaningful change in patient status . Score changes in the five different question naires were subjected to both distribution- and anchor-based methods : st and ard error of measurement ( SEM ) and receiver operating characteristic ( ROC ) curves to define clinical improvement . From these methods , the minimal clinical ly important difference ( MCID ) defined as the smallest difference that patients and clinicians perceive to be worthwhile is presented for each instrument . Based on the SEM , a point score change of 2.4 in the NRS , 5 in the RMDQ , 17 in the ODI , 11 on the PSEQ , and 1.4 on the PSFS corresponded to the MCID . Based on ROC curve analysis , a point score change of 4 points for both the NRS and RMDQ , 8 points for the ODI , 9 points for the PSEQ and 2 points for the PSFS corresponded to the MCID . The ROC analysis demonstrated that both the PSEQ and PSFS are responsive to clinical ly important change over time . The NRS was found to be least responsive . The exact value of the MCID is not a fixed value and is dependent on the assessment method used to calculate the score change . Based on ROC curve analysis the PSFS and PSEQ were more responsive than the other scales in measuring change in patients with chronic LBP following participation in a back class programme . However , due to the small sample size , the lack of observed worsening of symptoms over time , the single centre and intervention studied these results which need to be interpreted with caution Background The need for cost effectiveness analyses in r and omized controlled trials that compare treatment options is increasing . The selection of the optimal utility measure is important , and a central question is whether the two most commonly used indexes - the EuroQuol 5D ( EQ5D ) and the Short Form 6D ( SF6D ) – can be used interchangeably . The aim of the present study was to compare change scores of the EQ5D and SF6D utility indexes in terms of some important measurement properties . The psychometric properties of the two utility indexes were compared to a disease-specific instrument , the Oswestry Disability Index ( ODI ) , in the setting of a r and omized controlled trial for degenerative disc disease . Methods In a r and omized controlled multicentre trial , 172 patients who had experienced low back pain for an average of 6 years were r and omized to either treatment with an intensive back rehabilitation program or surgery to insert disc prostheses .  Patients filled out the ODI , EQ5D , and SF-36 at baseline and two-year follow up . The utility indexes was compared with respect to measurement error , structural validity , criterion validity , responsiveness , and interpretability according to the COSMIN taxonomy . Results At follow up , 113 patients had change score values  for all three instruments . The SF6D had better similarity with the disease-specific instrument ( ODI ) regarding sensitivity , specificity , and responsiveness . Measurement error was lower for the SF6D ( 0.056 ) compared to the EQ5D ( 0.155 ) . The minimal important change score value was 0.031 for SF6D and 0.173 for EQ5D . The minimal detectable change score value at a 95 % confidence level were 0.157 for SF6D and 0.429 for EQ5D , and the difference in mean change score values ( SD ) between them was 0.23 ( 0.29 ) and so exceeded the clinical significant change score value for both instruments . Analysis of psychometric properties indicated that the indexes are unidimensional when considered separately , but that they do not exactly measure the same underlying construct . Conclusions This study indicates that the difference in important measurement properties between EQ5D and SF6D is too large to consider them interchangeable . Since the similarity with the “ gold st and ard ” ( the disease-specific instrument ) was quite different , this could indicate that the choice of index should be determined by the diagnosis Study Design . Prospect i ve study of two sample s of patients with acute and chronic low back pain , respectively . Objectives . To compare the responsiveness of four functional status question naires , Rol and Morris Disability Question naire ( RMDQ ) ,  Oswestry Disability Index ( ODI ) ,  Disability Rating Index ( DRI ) , and  Physical Functioning scale of the SF-36 ( PFSF-36 ) , and two  pain scales , a  Numerical Pain Rating Scale ( NRS ) and  Visual Analogue Scale ( VAS ) .  Summary of Background Data . Concurrent comparisons of different outcome measurements in back patients have been requested . Methods .  Norwegian versions of the scales and question naires  were completed by 54 patients with acute ( < 3weeks ) and 50 patients with chronic low back pain ( > 3 months ) . Clinical change was estimated on a global change index . An alternative external criterion was the expected clinical course in the two cohorts . Mean changes , st and ardized response mean ( SRM ) , and area under the receiver operating characteristic ( ROC ) curves with cutoff point for highest sensitivity and specificity were calculated . Results . At the follow-up , 63 % of the acute and 41 % of the chronic sample reported improvement on the global change index . Large SRMs ( 1.3–2.0 ) and areas under the ROC curves ( 0.84–0.93 ) were found for the measurements in the acute sample . In the chronic sample , the SRMs ( 0.4–1.1 ) and areas under the ROC curves ( 0.65–0.83 ) were lower , in particular for the PFSF-36 and the VAS . There was no statistically significant difference between the responsiveness in the measurements , except for higher responsiveness in the NRS compared with the VAS when using expected clinical course as the external criterion for change . Conclusion . The results suggest that all the outcome measures were appropriate for measuring changes in functional status and pain in patients with acute low back pain , whereas among chronic patients the RMDQ , ODI , DRI , and NRS were most appropriate BACKGROUND CONTEXT Various method ologies have been used in attempting to eluci date a st and ard method for calculating minimal clinical ly important difference ( MCID ) . A consensus-based decision ( Initiative on Methods , Measurement , and Pain Assessment in Clinical Trials [ IMMPACT ] group ) suggested a 30 % reduction from baseline as a means to define the MCID of self-report back pain measures . Additionally , important psychometric issues need to be addressed regarding use of an independent measure of the same construct as an external criterion , instead of simply using another self-report measure , when using an anchor-based approach to MCID . PURPOSE The purpose was to test the validity of recently published guidelines regarding MCID using self-report back pain measures and objective socioeconomic outcomes . STUDY DESIGN / SETTING This is a prospect i ve study assessing change scores on commonly used spinal pain assessment measures in patients with chronic disabling occupational spinal disorders ( CDOSDs ) treated in a regional referral rehabilitation center performing interdisciplinary functional restoration . PATIENT SAMPLE The study consisted of consecutive cohort of patients ( N=1,180 ) with CDOSDs completing a functional restoration program . OUTCOMES MEASURES Self-report measures including the Oswestry Disability Index ( ODI ) and the physical component summary ( PCS ) and mental component summary ( MCS ) of the Short Form-36 ( SF-36 ) obtained before and after treatment , were compared with objective socioeconomically relevant outcomes obtained 1 year after treatment ( ie , work status and additional health-care utilization ) , that were the external criteria for evaluating MCID . METHODS Pre- to posttreatment improvement was calculated separately for each measure , and subjects were divided into two groups based on the change in scores relative to baseline : 30 % or greater versus less than 30 % improvement . One-year posttreatment objective socioeconomic outcomes were used as independent external criteria relevant to the CDOSD population . This population is often studied as the most costly and problematic cohort in spine care . RESULTS The ODI and SF-36 MCS were not associated with any of the objective 1-year outcomes used as external criteria . Reduced post-rehabilitation health-care utilization ( based on the percentage of patients pursuing health care from a new provider ) was weakly associated with 30 % or greater improvement on the SF-36 PCS , relative to patients whose scores changed by less than 30 % relative to baseline ( 17.0 % vs. 21.1 % ) . The same was true for the ODI and return-to-work . CONCLUSIONS When objective and independent criteria are used ( socioeconomic outcomes ) in a CDOSD cohort , the 30 % improvement in the ODI and SF-36 may not be a valid MCID index . This replicates similar conclusions made by an independent research group using a distribution-based approach to MCID . The validity of the MCID concept rests on future research using objective external criteria . Moreover , there remains a question whether the term " important " in MCID can be unequivocally and operationally defined as a reliable construct We r and omised a total of 94 patients with long-st and ing moderate lumbar spinal stenosis ( LSS ) into a surgical group and a non-operative  group , with 50 and 44 patients , respectively . The operative treatment comprised undercutting laminectomy of stenotic segments , augmented with transpedicular-instrumented fusion in suspected lumbar instability . The primary outcome was the Oswestry disability index ( ODI ) , and the other main outcomes included assessment s of leg and back pain and self-reported walking ability , all based on question naire data from 85 patients at the 6-year follow-up . At the 6-year follow-up , the mean difference in ODI in favour of surgery was 9.5 ( 95 % confidence interval 0.9–18.1 , P-value for global difference 0.006 ) , whereas the intensity of leg or back pain did not differ between the two treatment groups any longer . Walking ability did not differ between the treatment groups at any time . Decompressive surgery of LSS provided modest but consistent improvement in functional ability , surpassing that obtained after non-operative measures Abstract . The literature on the efficacy of traction in the treatment of low back pain ( LBP ) is conflicting . The aim of this study was to examine its efficacy in this disorder . Forty-two patients with at least 6 weeks of nonspecific LBP were selected . Demographic data were obtained . All patients completed the Oswestry disability index ( ODI ) to assess disability and the 10-cm visual analog scale ( VAS ) for evaluation of pain . Subjects were r and omly assigned into group 1 , receiving only st and ard physical therapy , or group 2 , receiving st and ard physical therapy with conventional lumbar traction . St and ard physical therapy consisted of local heat , ultrasound for the lumbar region , and an active exercise program , given for ten sessions in all . The subjects received instruction on correct posture and recommended therapeutic exercises . They were reevaluated at the end of treatment and at 3-month follow-up . The mean outcome measures were global improvement and satisfaction with the therapy , as well as disability by ODI and pain by VAS . There were no group differences in terms of demographic and baseline clinical characteristics . There was a significant reduction in pain intensity and disability at the end of treatment in both groups . There was complete or mild improvement in 47.6 % of group 1 and 40 % of group 2 . The satisfaction rate with both treatments was more than 70 % immediately after the therapies . During the 3-month period , the outcome measures except disability remained statistically stable , with no difference amongst groups . Disability was significantly reduced at follow-up in both groups . Of the patients , 51 % continued with the recommended exercises and had significantly lower disability scores than those who did not continue with the exercises . Pain and global improvement were also better in this group , but the difference was not statistically significant . In conclusion , no specific effect of traction on st and ard physical therapy was observed in our study group . We suggest focusing on back education and exercise therapy in the management of patients suffering from this chronic condition Study Design . Analysis of longitudinal data collected prospect ively from patients seen in 27 National Spine Network member centers across the United States . Objective . To evaluate the responsiveness of the Oswestry Disability Index , MODEMS scales , and all scales and summary scales of the MOS Short-Form 36 ( SF-36 ) for patients with low back pain/leg symptoms . Summary of Background Data . The responsiveness of general and condition-specific health status instruments is a key concept for clinicians and scientists . Various authors have explored responsiveness in common surveys used to assess spine patients . Although it is generally believed that condition-specific measures are more responsive to change in the condition under study , in the case of low back pain , most authors agree that further exploration is necessary . Methods . Patients with diagnoses of herniated disc , spinal stenosis , and spondylosis from the National Spine Network data base who completed baseline and 3-month follow-up surveys were analyzed . Patient-provider consensus regarding improvement , worsening , or no change in the condition was selected as the external criterion . Responsiveness was evaluated using ROC curve analysis and effect size calculations . Results . Nine hundred and seventy patients had complete data at baseline and 3 months . At follow-up , 68 % of the patients had consensus improvement . Based on ROC analysis , scales assessing pain were significantly more responsive than scales assessing function . There were no significant differences between the condition-specific scales and their equivalent general-health counterpart . The scales with the highest probabilities of correctly identifying patient ’s improvement were : the condition-specific pain scale from MODEMS ( PAIN , ROC = 0.758 ) ; the combined pain and function scale from MODEMS ( MPDL , ROC = 0.755 ) ; the general pain scale from the SF-36 ( BP , ROC = 0.753 ) ; the combined pain and function scale from the SF-36 ( PCS , ROC = 0.745 ) ; the condition-specific function measure from the Oswestry ( ODI , ROC = 0.723 ) ; and the physical function measure from the SF-36 ( PF , ROC = 0.721 ) . A similar rank order was typically maintained with effect size calculations . Results were nearly identical in patients with multiple non-spine-related comorbidities and in patients with high degrees of perceived  disability . The BP scale was most responsive to worsening of symptoms . Conclusion . For studies of patients with low back problems , the general SF-36 may be a sufficient measure of health status and patient function , without the need for additional condition-specific instruments .  Pain scales  appear to be the most responsive measures in patients with low back pain BACKGROUND CONTEXT Lumbar pathology is often associated with axial pain or neurologic complaints . It is often presumed that such pain is associated with decreased lumbar motion ; however , this correlation is not well established . The utility of various outcome measures that are used in both research and clinical practice have been studied , but the connection with range of motion ( ROM ) has not been well documented . PURPOSE The current study was performed to assess objective ly the postulated correlation of lumbar complaints ( based on st and ardized outcome measures ) with extremes of lumbar ROM and functional ROM ( fROM ) with activities of daily living ( ADLs ) as assessed with an electrogoniometer . STUDY DESIGN / SETTING This study was a clinical cohort study . PATIENT SAMPLE Subjects slated to undergo a lumbar intervention ( injection , decompression , and /or fusion ) were enrolled voluntarily in the study . OUTCOME MEASURES The two outcome measures used in the study were the Visual Analogue Scale ( VAS ) for axial extremity , lower extremity , and combined axial and lower extremity , as well as the Oswestry Disability Index ( ODI ) . METHODS Pain and disability scores were assessed with the  VAS score and ODI . A previously vali date d electrogoniometer was used to measure ROM ( extremes of motion in three planes ) and fROM ( functional motion during 15 simulated activities of daily living ) . Pain and disability scores were analyzed for statistically significant association with the motion assessment s using linear regression analyses . RESULTS Twenty-eight men and 39 women were enrolled , with an average age of 55.6 years ( range , 18 - 79 years ) . The ODI and VAS were associated positively ( p<.001 ) . Combined axial and lower extremity VAS scores were associated with lateral and rotational ROM ( p<.05 ) , but not with flexion/extension or any fROM . Similar findings were noted for separately analyzed axial and lower extremity VAS scores . On the other h and , the ODI correlated inversely with ROM in all planes , and fROM in at least one plane for 10 of 15 ADLs ( p<.05 ) . CONCLUSIONS Extremes of lumbar motion and motions associated with ADLs are of increasing clinical interest . Although the ODI and VAS are associated with each other , the ODI appears to be a better predictor of these motion parameters than the VAS ( axial extremity , lower extremity , or combined ) and may be more useful in the clinical setting when considering functional movement parameters Underst and ing changes in patient-reported outcomes is indispensable for interpretation of results from clinical studies . As a consequence the term “ minimal clinical ly important difference ” ( MCID ) was coined in the late 1980s to ease classification of patients into improved , not changed or deteriorated . Several method ological categories have been developed determining the MCID , however , all are subject to weaknesses or biases reducing the validity of the reported MCID . The objective of this study was to determine the reproducibility and validity of a novel method for estimating low back pain ( LBP ) patients ’ view of an acceptable change ( MCIDpre ) before treatment begins . One-hundred and forty-seven patients with chronic LBP were recruited from an out-patient hospital back pain unit and followed over an 8-week period . Original and modified versions of the Oswestry disability index ( ODI ) , Bournemouth question naire ( BQ ) and numeric pain rating scale  ( NRSpain ) were filled in at baseline . The modified question naires determined what the patient considered an acceptable post-treatment outcome which allowed us to calculate the MCIDpre . Concurrent comparisons between the MCIDpre , instrument measurement error and a retrospective approach of establishing the minimal clinical ly important difference ( MCIDpost ) were made . The results showed the prospect i ve acceptable outcome method scores to have acceptable reproducibility outside measurement error . MCIDpre was 4.5 larger for the ODI and 1.5 times larger for BQ and NRSpain compared to the MCIDpost . Furthermore , MCIDpre and patients post-treatment acceptable change was almost equal for the NRSpain but not for the ODI and BQ . In conclusion , chronic LBP patients have a reasonably realistic idea of an acceptable change in pain , but probably an overly optimistic view of changes in functional and psychological/affective domains before treatment begins Study Design . The Oswestry Disability Index v2.0 ( ODI ) , SF36 Physical Function Domain ( SF-36 PFD ) , and PROMIS Physical Function CAT v1.2 ( PF CAT ) question naires were prospect ively collected from 1607 patients complaining of back or leg pain , visiting a university-based spine clinic . All question naires were collected electronically , using a tablet computer . Objective . The aim of this study was to compare the psychometric properties of the PROMIS PF CAT with the ODI and SF36 Physical Function Domain in the same patient population . Summary of Background Data . Evidence -based decision-making is improved by using high- quality patient-reported outcomes measures . Prior studies have revealed the shortcomings of the ODI and SF36 , commonly used in spine patients . The PROMIS Network has developed measures with excellent psychometric properties . The Physical Function domain , delivered by Computerized Adaptive Testing ( PF CAT ) , performs well in the spine patient population , though to- date direct comparisons with common measures have not been performed . Methods . St and ard Rasch analysis was performed to directly compare the psychometrics of the PF CAT , ODI , and SF36 PFD . Spearman correlations were computed to examine the correlations of the three instruments . Time required for administration was also recorded . Results . One thous and six hundred seven patients were administered all assessment s. The time required to answer all items in the PF CAT , ODI , and SF-36 PFD was 44 , 169 , and 99 seconds . The ceiling and floor effects were excellent for the PF CAT ( 0.81 % , 3.86 % ) , while the ceiling effects were marginal and floor effects quite poor for the ODI ( 6.91 % and 44.24 % ) and SF-36 PFD ( 5.97 % and 23.65 % ) . All instruments significantly correlated with each other . Conclusion . The PROMIS PF CAT outperforms the ODI and SF-36 PFD in the spine patient population and is highly correlated . It has better coverage , while taking less time to administer with fewer questions to answer . Level of Evidence : BACKGROUND CONTEXT Given the unsustainable costs of the US health-care system , health-care purchasers , payers , and hospital systems are adopting the concept of value-based purchasing by shifting care away from low- quality providers or hospitals . Legislation now allows public reporting of these quality rankings . True measures of quality , such as surgical morbidity and vali date d question naires of effectiveness , are burdensome and costly to collect . Hence , patients ' satisfaction with care has emerged as a commonly used metric as a proxy for quality because of its feasibility of collection . However , patient satisfaction metrics have yet to be vali date d as a measure of overall quality of surgical spine care . PURPOSE We set out to determine whether patient satisfaction is a valid measure of safety and effectiveness of care in a prospect i ve longitudinal spine registry . STUDY DESIGN Prospect i ve longitudinal cohort study . PATIENT POPULATION All patients undergoing elective spine surgery for degenerative conditions over a 6-month period at a single medical center . OUTCOME MEASURES Patient-reported outcome instruments ( numeric rating scale [ NRS ] , Oswestry disability index [ ODI ] , neck disability index [ NDI ] , short-form 12-item survey [ SF-12 ] , Euro-Qol-5D [ EQ-5D ] , Zung depression scale , and Modified Somatic Perception Question naire [ MSPQ ] anxiety scale ) , return to work , patient satisfaction with outcome , and patient satisfaction with provider care . METHODS All patients undergoing elective spine surgery for degenerative conditions over a 6-month period at a single medical center were enrolled into a prospect i ve longitudinal registry . Data collected on all patients included demographics , disease characteristics , treatment variables , readmissions/reoperations , and all 90-day surgical morbidity . Patient-reported outcome instruments ( NRS , ODI , NDI , SF-12 , EQ-5D , Zung depression scale , and MSPQ anxiety scale ) , return to work , patient satisfaction with outcome , and patient satisfaction with provider care were recorded at baseline and 3 months after treatment . Receiver-operating characteristic ( ROC ) curve analysis was performed to determine whether extent of improvement in quality of life ( SF-12 physical component summary [ PCS ] ) and disability ( ODI/NDI ) accurately predicted patient satisfaction versus dissatisfaction . St and ard interpretation of area under the curve ( AUC ) was used : less than 0.7 , poor ; 0.7 to 0.8 , fair ; and greater than 0.8 , good accuracy . Multivariate logistic regression analysis was performed to determine if surgical morbidity ( quality ) or improvement in disability and quality of life ( effectiveness of care ) were independently associated with patient satisfaction . RESULTS Four hundred twenty-two ( 84 % ) patients completed all question naires 3 months after surgery during the review ed time period ( mean age 55±14 years ) . Lumbar surgery was performed in 287 ( 68 % ) and cervical surgery in 135 ( 32 % ) patients . There were 51 ( 12.1 % ) 90-day complications , including 21 ( 5.0 % ) readmissions and 12 ( 2.8 % ) return to operating room . Three hundred fifty-eight ( 84.8 % ) patients were satisfied with provider care and 288 ( 68.2 % ) with their outcome . Satisfaction with provider care : In ROC analyses , extent of improvement in quality of life ( SF-12 ) and disability ( ODI/NDI ) differentiated satisfaction versus dissatisfaction with care with very poor accuracy ( AUC 0.49 - 0.69 ) . In regression analysis , 3-month morbidity ( odds ratio [ 95 % confidence interval ] : 1.45 [ 0.79 - 2.66 ] ) , readmission ( 0.66 [ 0.24 - 1.80 ] ) , improvement in quality of life ( SF-12 PCS ) , or improvement in general health ( health transition index ) were not associated with satisfaction with care . Satisfaction with outcome : In ROC analyses , improvement in quality of life ( SF-12 ) and disability ( ODI/NDI ) failed to differentiate satisfaction with good accuracy ( AUC 0.76 ) . Neither 90-day morbidity ( 1.05 [ 0.46 - 2.34 ] ) nor 90-day readmission ( 0.27 [ 0.04 - 2.04 ] ) was associated with satisfaction with outcome in regression analysis . CONCLUSIONS Patient satisfaction is not a valid measure of overall quality or effectiveness of surgical spine care . Patient satisfaction metrics likely represent the patient 's subjective contentment with health-care service , a distinct aspect of care . Satisfaction metrics are important patient-centered measures of health-care service but should not be used as a proxy for overall quality , safety , or effectiveness of surgical spine care Study Design . The Shuttle Walking Test ( SWT ) , the Swiss Spinal Stenosis ( SSS ) Question naire , the Oxford Claudication Score ( OCS ) , and the Oswestry Disability Index ( ODI ) were administered to patients with lumbar spinal stenosis and neurogenic claudication . Objective . To determine reliability of the SWT , the SSS ( Q1–12 ) , the OCS , and the ODI in lumbar spinal stenosis assessment . Summary of Background Data . Reliability data for exercise tests in lumbar spinal stenosis are lacking . Methods . To determine reliability , 32 clinic patients with lumbar spinal stenosis were assessed twice , with 1 week between assessment s. Retrospective data from 17 patients assessed before surgery and 18 months after surgery for lumbar spinal stenosis were used to investigate the use of reliability in a clinical setting . Results . Test – retest reliability in terms of the intraclass correlation coefficient ( ICC ) was 0.92 for the SWT , 0.92 for the SSS , 0.83 for the OCS and 0.89 for the ODI . The mean percentage scores were 51 for the SSS , 45 for the OCS , and 40 for the ODI . To achieve 95 % certainty of change between assessment s for a single patient , the SSS would need to change by 15 , the OCS by 20 , and the ODI by 16 . The mean SWT was 150 m , with a change of 76 m required for 95 % confidence . Cronbach ’s alpha was 0.91 for the SSS , 0.90 for the OCS , and 0.89 for the ODI . The change in ODI correlated most strongly with patient satisfaction after surgery ( & rgr ; = 0.80;P < 0.001 ) . Conclusions . Fluctuations in a patient ’s symptoms result in wide individual confidence intervals . Performance on the SSS , OCS , and ODI question naires are broadly similar , the most precise being the condition-specific SSS . The SWT gives a snapshot of physical function , which is acceptable for group analysis . Use of the SWT for individual assessment after surgery is feasible Purpose The aim of this longitudinal study is to determine the factors which predict a successful 1-year outcome from an intensive combined physical and psychological ( CPP ) programme in chronic low back pain ( CLBP ) patients . Methods A prospect i ve cohort of 524 selected consecutive CLBP patients was followed . Potential predictive factors included demographic characteristics , disability , pain and cognitive behavioural factors as measured at pre-treatment assessment . The primary outcome measure was the oswestry disability index ( ODI ) . A successful 1-year follow-up outcome was defined as a functional status equivalent to ‘ normal ’ and healthy population s ( ODI ≤22 ) . The 2-week residential programme fulfills the recommendations in international guidelines . For statistical analysis we divided the data base into two equal sample s. A r and om sample was used to develop a prediction model with multivariate logistic regression . The remaining cases were used to vali date this model . Results The final predictive model suggested being ‘ in employment ’ at pre-treatment [ OR 3.61 ( 95 % CI 1.80–7.26 ) ] and an initial ‘ disability score ’ [ OR 0.94 ( 95 % CI 0.92–0.97 ) ] as significant predictive factors for a successful 1-year outcome ( R2 = 22 % ; 67 % correctly classified ) . There was no predictive value from measures of psychological distress . Conclusion CLBP patients who are in work and mild to moderately disabled at the start of a CPP programme  are most likely to benefit from it and to have a successful treatment outcome . In these patients , the disability score falls to values seen in healthy population s. This small set of factors is easily identified , allowing selection for programme entry and triage to alternative treatment regimes BACKGROUND CONTEXT Surgical treatment for lumbar degenerative disc disease ( DDD ) has been associated with highly variable results in terms of postoperative pain relief and functional improvement . Many experts believe that DDD should be considered a chronic pain disorder as opposed to a degenerative disease . Genetic variation of the catechol-O-methyltransferase ( COMT ) gene has been associated with variation in human pain sensitivity and response to analgesics in previous studies . PURPOSE To determine whether genetic variation of COMT is associated with clinical outcome after surgical treatment for DDD . STUDY DESIGN Prospect i ve genetic association study . PATIENT SAMPLE Sixty-nine patients undergoing surgical treatment for lumbar DDD . Diagnosis was based on documentation of chronic disabling low back pain ( LBP ) present for a minimum of 6 months and unresponsive to supervised nonoperative treatment , including activity modification , medication , physical therapy , and /or injection therapy . Plain radiographs and magnetic resonance imaging revealed intervertebral disc desiccation , tears , and /or collapse without focal herniation , nerve root compression , stenosis , spondylolisthesis , spondylolysis , or alternative diagnoses . OUTCOME MEASURES Oswestry Disability Index ( ODI ) and visual analog score ( VAS ) for LBP . METHODS Surgical treatment included 65 instrumented fusions and four disc arthroplasty procedures . All patients completed preoperative and 1-year postoperative ODI question naires . DNA was extracted from a sample of venous blood , and genotype analysis was performed for five common COMT single nucleotide polymorphisms ( SNPs ) . Potential genetic association between these COMT SNPs and the primary outcome variable , 1-year change in ODI , was investigated using both single-marker and haplotype association analyses . Association with VAS scores for LBP was analyzed as a secondary outcome variable . RESULTS Single-marker analysis revealed that the COMT SNP rs4633 was significantly associated with greater improvement in ODI score 1 year after surgery ( p=.03 ) , with individuals homozygous for the less common " T " allele demonstrating the largest improvement in ODI . Haplotype analysis of four COMT SNPs , rs6269 , rs4633 , rs4818 , and rs4680 , also identified a common haplotype " ATCA " ( haplotype frequency of 39.3 % in the study population ) associated with greater improvement in ODI ( p=.046 ) . The greatest mean improvement in ODI was observed in patients homozygous for the " ATCA"COMT haplotype . A nonsignificant trend was observed between SNP rs4633 and greater improvement in VAS score for LBP . CONCLUSIONS This is the first study to report an association between surgical treatment success in DDD patients and genetic variation in the putative pain sensitivity gene COMT . These findings require replication in other DDD population s but suggest that genetic testing for pain-relevant genetic markers such as COMT may provide useful clinical information in terms of predicting outcome after surgery for patients diagnosed with DDD BACKGROUND CONTEXT Objective measures including neurological findings , radiographic evaluation , and the Japanese Orthopaedic Association ( JOA ) score are commonly used for the evaluation of surgical outcomes . Because many surgeries are performed primarily to improve quality of life , a patient 's subjective evaluations are also important for accurately assessing surgical outcomes . Currently available instruments for assessing quality of life include the Short-Form 36 ( F-36 ) , the Oswestry disability index ( ODI ) , and the visual analog scale ( VAS ) clinical pain scale . PURPOSE The aims of this study were to measure surgical outcomes by using both objective measures and subjective measures including patient self- assessment s and psychological changes ; to assess the adequacy of the JOA alone for measuring outcome ; and to determine which measures , the SF-36v2 , ODI , VAS , or JOA correlate with the VAS pain scale score in lumbar canal stenosis . STUDY DESIGN We performed a prospect i ve study to measure surgical outcomes for lumbar canal stenosis using traditional objective measures such as neurological findings and subjective measures such as performance of ADLs , patient self- assessment s , and psychological changes . PATIENT SAMPLE Forty-two surgical patients with a mean age of 66.8+/-10.9 years at the time of surgery were included in the study . All cases were followed for more than 2 years . Surgical indications included no response to conservative treatment and neurological deterioration . Neurological symptoms were classified as nerve root type , cauda equine type , or combined type . We performed surgical decompression at the location of the dural or root indentation by myelography . The concomitant diagnosis causing the spinal stenosis was degenerative spondylolisthesis in 20 cases undergoing posterolateral fusion with pedicle screws . OUTCOME MEASURES Surgical outcomes were assessed by comparing preoperative and 24-month postoperative JOA scores for low back pain , SF-36v2 , ODI-v2 , and VAS scores . Statistical analysis was performed by using the analysis of variance . A p value<0.05 was considered statistically significant . METHODS Objective clinical measures , patient self- assessment s , and psychological changes were measured before and at 24 months postoperatively . We also examined which measurements correlated with the VAS scale for pain evaluation , thereby relating patient satisfaction to surgery outcome . RESULTS All JOA , SF-36v2 , ODI-v2 , and VAS scores significantly improved postoperatively . The physical component summary ( PCS ) of the SF-36 v2 showed significant improvement , although all scores remained less than the Japanese norm-based scores ( NBSs ) . The mental component summary ( MCS ) exhibited such a significant improvement that all postoperative subscales were higher than the Japanese NBS . JOA scores significantly correlated only with postoperative lower-extremity VAS score . All PCS and two MCS scores significantly correlated with the VAS score for low back pain . Parts of the PCS and MCS significantly correlated with the lower-extremity VAS . The ODI significantly correlated with both the preoperative and postoperative VAS scores for low back pain as well as with the postoperative lower-extremity VAS score . CONCLUSIONS The JOA , SF-36 , ODI , and VAS question naires are all useful instruments for measuring surgical outcomes . The VAS score is a better assessment of physical rather than mental health . The ODI is more reflective of patients ' subjective symptoms . Finally , the SF-36 is particularly informative because it includes questions addressing both psychological and physical status . Therefore , when combined , the SF-36v2 , VAS , and ODI scores are a valuable complement to the JOA scores in evaluating outcomes of surgery for lumbar canal stenosis Objective To introduce a newly design ed massage instrument , the H and Grip T-bar ( HT-bar ) and use it to relieve chronic non-specific low back pain ( nLBP ) through deep cross-friction massage ( roptrotherapy ) . Method 22 subjects ( 9 males and 13 females , aged 51.6±6.7 ) with chronic nLBP were allocated r and omly to a Roptrotherapy group ( n=12 ) and a Transcutaneous Electrical Nerve Stimulation ( TENS ) group ( n=10 ) . The Roptrotherapy group received deep cross-friction massage with the HT-bar , which was made of metal and had a cylinder for increasing weight and grooves for an easy grip . It was applied across the middle and lower back for 20 minutes a day , 3 days a week for 2 weeks . The TENS group received TENS for 20 minutes a day , 5 days a week for 2 weeks . The outcome was measured on the pain numeric rating scale ( PNRS ) , by the Oswestry disability index ( ODI ) , and by the Rol and & Morris Disability Question naire ( RMDQ ) at pre-treatment , at immediate post-treatment and 2 weeks later . The application of the HT-bar was assessed by a question naire to 19 therapists . Results At post-treatment , immediately and 2 weeks later , both groups showed significant improvement in PNRS , ODI and RMDQ . During the two weeks after post-treatment , however , the Roptrotherapy group improved in PNRS , ODI and RMDQ , but the TENS group did not . Over 80 % of the therapists responded that the HT-bar was useful and comfortable . Conclusion This study suggests that deep cross-friction massage can be a beneficial therapeutic technique and that the HT-bar can be a useful instrument in deep cross-friction massage for chronic nLBP patients Study Design . A review of the surgical costs and results in a group of patients r and omly allocated to surgery as part of a large prospect i ve r and omized trial of patients with chronic back pain . Objective . To report the observational data from the surgical arm of a r and omized trial comparing surgery with intensive rehabilitation for chronic low back pain . Clinical and economic data are reported . Summary of Background Data . Surgery for chronic low back pain is a well established but unproven intervention . The most cost-effective technique for spinal stabilization is still not established . Methods . One hundred six patients with chronic low back pain were r and omized to the surgical group of a r and omized trial comparing spinal fusion of the lumbar with a 3 week intensive rehabilitation program . The primary outcomes were the Oswestry Disability Index ( ODI ) and the Shuttle Walking Test measured at baseline and 2 years postr and omization . Patients were stratified by preoperative diagnosis , smoking habit , and litigation . Complications were assessed and costs analyzed . Results . Of the 176 surgical patients , 56 underwent postero-lateral fusion , 57 underwent interbody fusion , and 24 underwent flexible stabilization of the spine . The mean ODI for all patients in the surgical arm of the trial improved from a baseline of 46.5 ( SD 14.6 ) to 34.2 ( SD 21 ) at 2 years . Health care costs were higher ( £ 3109 difference ) for more complex procedures , and nearly 6 times as many early complications occurred with the more complex procedures . Smoking and unemployment were associated with worse results whereas litigation did not adversely affect the outcome . Conclusion . These observational changes in the ODI after surgery are similar to those reported from other studies of spinal fusion . More complex surgery is more expensive with more complications than postero-lateral fusion BACKGROUND CONTEXT Chronic low back pain ( cLBP ) represents a major challenge to our health care systems . The relative efficacy of surgery over nonoperative treatment for the treatment of cLBP remains controversial , and little is known of the long-term comparative outcomes . PURPOSE To compare the clinical outcome at long-term follow-up ( LTFU ) of patients who were r and omized with either spinal fusion or multidisciplinary cognitive-behavioral and exercise rehabilitation for cLBP . STUDY DESIGN / SETTING Long-term clinical follow-up of three multicenter r and omized controlled trials ( RCTs ) of surgery ( instrumented or noninstrumented fusion , stabilization ) versus nonoperative treatment ( multidisciplinary cognitive-behavioral and exercise rehabilitation ) in Norway and the United Kingdom . PATIENT SAMPLE A total of 473 patients with cLBP of at least 1 year 's duration who were all considered c and i date s for spinal fusion . OUTCOME MEASURES The primary outcome was the Oswestry Disability Index ( ODIv2.1a for the United Kingdom and ODIv1 for Norway ) score measured at LTFU . Secondary outcomes included visual analog scale ( VAS ) pain intensity , pain frequency , pain medication use , work status , EuroQol VAS for health-related quality of life , satisfaction with care , and global treatment outcome at LTFU . METHODS Patients who consented to LTFU ( average 11.4 [ range 8 - 15 ] years after the initial treatment ) completed the outcome question naires . RESULTS Of 473 enrolled patients , 261 ( 55 % ) completed LTFU , 140/242 patients r and omized to receive surgery and 121/231 r and omized to receive multidisciplinary cognitive-behavioral and exercise rehabilitation . The intention-to-treat analysis showed no statistically or clinical ly significant differences between treatment groups for ODI scores at LTFU ( adjusted for baseline ODI , previous surgery , duration of LBP , sex , age , and smoking habit ) : the mean adjusted treatment effect of fusion was -0.7 points on the 0 - 100 ODI scale ( 95 % confidence interval [ CI ] , -5.5 to 4.2 ) . An as-treated analysis similarly demonstrated no advantage of surgery ( treatment effect , -0.8 points on the ODI ( 95 % CI , -5.9 to 4.3 ) . The results for the secondary outcomes were largely consistent with those of the ODI , showing no relevant group differences . CONCLUSIONS After an average of 11 years follow-up , there was no difference in patient self-rated outcomes between fusion and multidisciplinary cognitive-behavioral and exercise rehabilitation for cLBP . The results suggest that , given the increased risks of surgery and the lack of deterioration in nonoperative outcomes over time , the use of lumbar fusion in cLBP patients should not be favored in health care systems where multidisciplinary cognitive-behavioral and exercise rehabilitation programmes are available OBJECTIVE : Preliminary studies have suggested that prolonged retraction of the paraspinal muscle during spinal surgery may produce ischemic damage . We report the continuous measurement of intramuscular pressure ( IMP ) during decompressive lumbar laminectomy and its relationship to subsequent back pain and disability . METHODS : Twenty patients undergoing two-level decompressive lumbar laminectomy for lumbar canal stenosis were recruited .  Back pain and disability were assessed by use of the Visual Analog Score ( VAS ) , Oswestry Disability Index ( ODI ) , and Short-Form 36 ( SF-36 ) Health Survey . During surgery , IMP was recorded continuously from the multifidus muscle by use of a pressure transducer . The intramuscular perfusion pressure ( IPP ) was estimated as the difference between the patient 's mean arterial pressure and IMP . RESULTS : Two muscle retractors were used : the Norfolk and Norwich ( n = 10 ) and the McCulloch ( n = 10 ) . The mean duration of deep muscle retraction was 62.7 ± 8 minutes ( range , 19–133 min ) . On application of deep muscle retraction , there was a rapid and sustained increase in IMP ( P < 0.001 ) , and overall , the calculated mean IPP approached 0 mm Hg or less during this period ( P < 0.001 ) . On release of deep muscle retraction , there was a rapid decrease in IMP to preoperative levels . The IPP was greater with the Norfolk and Norwich than the McCulloch retractor ( P < 0.001 ) . Compared with preoperative values , there was a decrease in ODI ( P < 0.001 ) and VAS for back pain ( P < 0.001 ) at discharge and 4 to 6 weeks and 6 months after surgery . In addition , there was a decrease in SF-36 scores at 6 months compared with preoperative values ( P < 0.001 ) . Total duration of muscle retraction greater than 60 minutes was associated with worse VAS scores for back pain and ODI and SF-36 scores for disability at 6 months after surgery ( P < 0.05 ) . There was no relationship between the VAS , ODI , and SF-36 scores and other parameters measured , including the mean IPP , retractor type , operating surgeon , and wound length . CONCLUSION : The McCulloch retractor generates a higher IMP than the Norfolk and Norwich retractor . However , postoperative improvement in VAS , ODI , and SF-36 scores in these patients was associated with a shorter duration of muscle retraction and not the degree of IMP or IPP generated . In this respect , periodic relaxation of the paraspinal muscle retractors during surgery to allow muscle perfusion may help to reduce postoperative back pain and disability The effect of the duration of symptoms on the outcome of lumbar decompression surgery is not known . The aim of our study was to determine the predictors of functional outcome of lumbar decompression surgery for degenerative spinal stenosis with particular emphasis on the duration of symptoms . In this prospect i ve cohort study , we recruited 100 patients with a full data set available at 1-year and 85 % at 2-year follow-ups : 49 females and 51 males with an average age of 62 ( range 52–82 ) . The pre- and post-operative outcome measures were Oswestry disability index ( ODI ) , low back outcome score ( LBOS ) , pain visual analogue score ( VAS ) , modified somatic perception ( MSP ) and modified Zung depression ( MZD ) score . Dural tear occurred in 14 % , and there was one post-operative extra-dural heamatoma . Overall , the ODI improved from a pre-operative of 56 ( ±13 ) to a 1-year ODI of 40 ( ±22 ) and at 2-year ODI of 40 ( ±21 ) . The VAS improved from an average of 8 to 5.2 at 1 year and 4.9 at 2 years . There was a statistical significant association between symptom duration and the change in ODI ( P=0.007 at 1-year follow-up , P=0.001 at 2-year follow-up ) , LBOS ( P=0.001 at 1-year follow-up , P<0.001 at 2-year follow-up ) and VAS ( P=0.003 at 1-year follow-up , P=0.001 at 2-year follow-up ) . Subgroup analyses showed that patients with symptom duration of less than 33 months had a more favourable result . In addition , the patients who rated the operation as excellent had a statistically significantly shorter duration of symptoms . We have not found a predictive value for age at operation , MSP or MZD . The number of levels of decompression and the different types of decompression surgery did not influence the surgical results . Our study indicates that the symptom duration of more than 33 months has a less favourable functional outcome
The ODI remains a valid and vigorous measure and has been a worthwhile outcome measure .
The behavior of the instrument is incompletely understood , particularly in sensitivity to real change .
The Oswestry Disability Index ( ODI ) has become one of the principal condition-specific outcome measures used in the management of spinal disorders .
To review the versions of this instrument , document methods by which it has been vali date d , collate data from scores found in normal and back pain population s , provide curves for power calculations in studies using the ODI , and maintain the ODI as a gold st and ard outcome measure .
It has now been 20 years since its original publication .