human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Study Design . A prospect i ve repeated- measures design was applied . Objectives . To examine the measurement properties of the Back Pain Functional Scale ( BPFS ) and the Rol and –Morris Question naire ( RMQ )  and to formulate hypotheses and sample size estimates for a subsequent comparison study . Summary of Background Data . Although there are numerous functional status measures for patients with low back pain , most have been conceived of and vali date d with a group rather than an individual patient as the unit of interest . Also , little has been done to formally compare — this includes the generation of a priori hypotheses , followed by statistical hypotheses testing — the many competing measures . Methods . Subjects were 77 patients with low back pain who were referred by physicians to 10 outpatient physical therapy clinics located in Canada and the United States . The question naires were administered at patients ’ initial visits , within 48 hours of the initial visit , and at 1- , 2- , and 3-week follow-up visits . Reliability , cross-sectional validity , and longitudinal validity ( sensitivity to change ) coefficients were calculated . Results . Test – retest reliability estimates of 0.81 and 0.88 were obtained for the RMQ and BPFS , respectively . The measures demonstrated similar levels of cross-sectional validity . Correlations of 0.56 and 0.65 were noted between a prognostic rating of change and the RMQ and BPFS , respectively . The RMQ demonstrated a ceiling effect .  Approximately 180 patients are needed for a subsequent head-to-head comparison study of the measures . Conclusions . The BPFS appears to have sound measurement properties , and a formal head-to-head comparison study with the RMQ is warranted 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 Chronic low-back pain is a significant public health problem for which few therapies are supported by predictable outcomes . In this report , practice activities and 1-month outcomes data are presented for 93 chiropractic patients and 45 medical patients with chronic , recurrent low-back pain . DESIGN A prospect i ve , observational , community-based feasibility study involving chiropractors and family medicine physicians . SETTING Forty private chiropractic clinics , the outpatient clinic of the Department of Family Medicine at Oregon Health Sciences University , and 5 other Portl and area family medicine clinics . OUTCOMES MEASURES The main outcome measures were pain severity , functional disability , sensory and affective pain quality at 1 month , and patient satisfaction assessed at 7 to 10 days and at 1 month . RESULTS Although differences were noted in age , sex , education , and employment , the patients were closely matched at baseline with respect to frequency , severity , and type of low-back pain and the psychosocial dimensions of general health . The treatment of choice for chiropractors was spinal manipulation and physical therapy modalities ; for medical physicians antiinflammatory agents were most frequently used . Chiropractic patients averaged 4 visits , and medical patients averaged 1 visit . On average , chiropractic patients showed improvement across all outcomes : 31 % change in pain severity , 29 % in functional disability , 36 % in sensory pain quality , and 57 % in affective pain quality . Medical patients showed minimal improvement in pain severity ( 6 % ) and functional disability ( 1 % ) and showed deterioration in the sensory ( 29 % ) and affective ( 26 % ) dimensions of pain quality . Satisfaction scores were higher for chiropractic patients . Outcomes for medical patients were heavily dependent on psychosocial status at baseline . CONCLUSION Patients with chronic low-back pain treated by chiropractors show greater improvement and satisfaction at 1 month than patients treated by family physicians . Non clinical factors may play an important role in patient progress . Findings from the Health Re sources and Services Administration-funded project will include a report on the influence of practice activities , including more frequent visits by chiropractic patients , on the clinical course of low-back pain and patient outcomes . ( J Manipulative Physiol Ther 2000;23:239 - 45 ) STUDY DESIGN A prospect i ve , cross-sectional study of the correlation between postoperative computed tomography findings and patients ' clinical outcomes approximately 4 years after laminectomy for lumbar spinal stenosis . OBJECTIVES To evaluate clinical and radiologic characteristics and their relation to each other . SUMMARY OF BACKGROUND DATA The goal of surgical management for lumbar spinal stenosis is to decompress the stenotic area determined in radiologic examinations to relieve pressure on the neurovascular structures . However , the success of this decompression very rarely has been confirmed by postoperative radiologic imaging or compared with clinical outcome . METHODS Postoperative computed tomography was performed on 191 patients . The findings were classified as " no stenosis , " " central stenosis , " " lateral stenosis , " or " central -lateral stenosis . " Postoperative instability of the lumbar spine was investigated by functional radiography . Clinical status was assessed by clinical examination . Subjective disability was assessing using the Oswestry question naire , and severity of pain using the visual analog scale . Walking capacity was evaluated by the tread-mill test . RESULTS Radiologic studies revealed postoperative stenosis  in 123 patients ( 64 % ) . Small differences between the computed tomography groups were shown for the Oswestry score , but not for walking distance . Clinical signs , severity of pain , and radiologic instability were very similar for all computed tomography groups . CONCLUSIONS Postoperative radiologic stenosis was very common in patients operated on for lumbar spinal stenosis , but this did not correlate with clinical outcome . The clinician must be cautious when reconciling clinical symptoms and signs with postoperative computed tomography findings in patients operated on for lumbar spinal stenosis STUDY DESIGN A double-blind , r and omized controlled trial of a novel educational booklet compared with a traditional booklet for patients seeking treatment in primary care for acute or recurrent low back pain . OBJECTIVE To test the impact of a novel educational booklet on patients ' beliefs about back pain and functional outcome . SUMMARY OF BACKGROUND DATA The information and advice that health professionals give to patients may be important in health care intervention , but there is little scientific evidence of their effectiveness . A novel patient educational booklet , The Back Book , has been developed to provide evidence -based information and advice consistent with current clinical guidelines . METHODS One hundred sixty-two patients were given either the experimental booklet or a traditional booklet . The main outcomes studied were fear-avoidance beliefs about physical activity , beliefs about the inevitable consequences of back trouble , the Rol and Disability Question naire , and visual analogue pain scales . Postal follow-up response at 1 year after initial treatment was 78 % . RESULTS Patients receiving the experimental booklet showed a statistically significant greater early improvement in beliefs which was maintained at 1 year . A greater proportion of patients with an initially high fear-avoidance beliefs score who received the experimental booklet had clinical ly important improvement in fear-avoidance beliefs about physical activity at 2 weeks , followed by a clinical ly important improvement in the Rol and Disability Question naire score at 3 months . There was no effect on pain . CONCLUSION This trial shows that carefully selected and presented information and advice about back pain can have a positive effect on patients ' beliefs and clinical outcomes , and suggests that a study of clinical ly important effects in individual patients may provide further insights into the management of low back pain Study Design . A prospect i ve cohort study of patients with subacute occupational back pain . Objectives . To study the relation between a marketed opto‐electric device measuring trunk kinematics , a widely used specific functional capacity question naire , and work status in back pain patients , and to assess the responsiveness to change in work status of the opto‐electric device and the question naire . Summary of Background Data . Several instruments have been developed to evaluate the functional capacities of patients with back pain , but the relation between these instruments and work status has rarely been studied . Methods . The relation between the opto‐electric device , the question naire , and work status in patients with back pain was evaluated . The study population was a prospect i ve cohort of patients with subacute back pain who were absent from regular work for more than 4 weeks . All data were compiled blindly on the same day , at study entry ( 4 weeks after work accident ) , and at 12 , 24 , and 52 weeks after the work accident . The validity of the question naire and opto‐electric device scores was assessed with partial correlation analyses , st and ardized response mean , logistic regression analyses , and receiver operating characteristics curves . Results . The correlation between the question naire and opto‐electric device scores was low . The question naire scores were significantly related to work status , but the opto‐electric device scores were not . The question naire was responsive to change in work status , whereas the opto‐electric device was not . Conclusions . The opto‐electric device scores were not related to either functional capacity scores ( question naire ) or work status in patients with low back pain , and the opto‐electric device was not responsive to change in work status . Conversely , the question naire was related to work status and was responsive to change in work status OBJECTIVE Previous studies have shown that cortical-evoked potentials on magnetic stimulation of muscles are influenced by muscle contraction , vibration , and muscle spasm . This study was carried out to determine whether these potentials correlate with palpatory muscle spasm , patient symptoms , and disability in patients with low back pain . METHODS A prospect i ve observational study was performed on 13 subjects with a history of low back pain visiting an orthopedic hospital-based clinic . Patients were screened for serious pathologic conditions by an orthopedic surgeon . The patients were then evaluated for the presence of muscle spasm by one of the investigators who was blinded to the results of the evoked potential studies . Patients were asked to complete a  low back pain visual analogue scale ( VAS ) and a Rol and -Morris Activity Scale ( RMAS ) . Cortical-evoked potentials were recorded with a magnetic stimulator placed over the lumbar paraspinal muscles with the patient in the prone position . The palpatory examination , VAS , RMAS , and the cortical potentials were repeated after 2 weeks of therapy commonly used to reduce muscle spasm . RESULTS The patients demonstrated a significant decrease in low back pain VAS and RMAS scores after treatment compared with before treatment . There was a reduction in the amount of palpatory muscle spasm in 11 of 13 cases . The cortical potentials before treatment were attenuated compared with previously reported controls and showed a significant increase before and after treatment in the amplitude of these potentials with multivariate analysis of variance . There was significant correlation between the changes in cortical potentials after treatment and the changes noted in paraspinal muscle spasm and VAS and RMAS scores . CONCLUSIONS This study confirms the previous report that the amplitude of cerebral-evoked potentials on magnetic stimulation of paraspinal muscles is depressed in the presence of palpable muscle spasm . The close correlation among these potentials , paraspinal muscle spasm , and clinical symptoms suggests that the measurement of muscle activity may be more important in the assessment of low back pain than is commonly accepted 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 
    Output:
    
agent
Most of the outcome question naires had a mixed content reflecting various constructs such as pain and symptoms , sleep disturbances , psychological dysfunctions , physical impairments , and social functions .
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Study Design . A prospect i ve repeated- measures design was applied . Objectives . To examine the measurement properties of the Back Pain Functional Scale ( BPFS ) and the Rol and –Morris Question naire ( RMQ )  and to formulate hypotheses and sample size estimates for a subsequent comparison study . Summary of Background Data . Although there are numerous functional status measures for patients with low back pain , most have been conceived of and vali date d with a group rather than an individual patient as the unit of interest . Also , little has been done to formally compare — this includes the generation of a priori hypotheses , followed by statistical hypotheses testing — the many competing measures . Methods . Subjects were 77 patients with low back pain who were referred by physicians to 10 outpatient physical therapy clinics located in Canada and the United States . The question naires were administered at patients ’ initial visits , within 48 hours of the initial visit , and at 1- , 2- , and 3-week follow-up visits . Reliability , cross-sectional validity , and longitudinal validity ( sensitivity to change ) coefficients were calculated . Results . Test – retest reliability estimates of 0.81 and 0.88 were obtained for the RMQ and BPFS , respectively . The measures demonstrated similar levels of cross-sectional validity . Correlations of 0.56 and 0.65 were noted between a prognostic rating of change and the RMQ and BPFS , respectively . The RMQ demonstrated a ceiling effect .  Approximately 180 patients are needed for a subsequent head-to-head comparison study of the measures . Conclusions . The BPFS appears to have sound measurement properties , and a formal head-to-head comparison study with the RMQ is warranted 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 Chronic low-back pain is a significant public health problem for which few therapies are supported by predictable outcomes . In this report , practice activities and 1-month outcomes data are presented for 93 chiropractic patients and 45 medical patients with chronic , recurrent low-back pain . DESIGN A prospect i ve , observational , community-based feasibility study involving chiropractors and family medicine physicians . SETTING Forty private chiropractic clinics , the outpatient clinic of the Department of Family Medicine at Oregon Health Sciences University , and 5 other Portl and area family medicine clinics . OUTCOMES MEASURES The main outcome measures were pain severity , functional disability , sensory and affective pain quality at 1 month , and patient satisfaction assessed at 7 to 10 days and at 1 month . RESULTS Although differences were noted in age , sex , education , and employment , the patients were closely matched at baseline with respect to frequency , severity , and type of low-back pain and the psychosocial dimensions of general health . The treatment of choice for chiropractors was spinal manipulation and physical therapy modalities ; for medical physicians antiinflammatory agents were most frequently used . Chiropractic patients averaged 4 visits , and medical patients averaged 1 visit . On average , chiropractic patients showed improvement across all outcomes : 31 % change in pain severity , 29 % in functional disability , 36 % in sensory pain quality , and 57 % in affective pain quality . Medical patients showed minimal improvement in pain severity ( 6 % ) and functional disability ( 1 % ) and showed deterioration in the sensory ( 29 % ) and affective ( 26 % ) dimensions of pain quality . Satisfaction scores were higher for chiropractic patients . Outcomes for medical patients were heavily dependent on psychosocial status at baseline . CONCLUSION Patients with chronic low-back pain treated by chiropractors show greater improvement and satisfaction at 1 month than patients treated by family physicians . Non clinical factors may play an important role in patient progress . Findings from the Health Re sources and Services Administration-funded project will include a report on the influence of practice activities , including more frequent visits by chiropractic patients , on the clinical course of low-back pain and patient outcomes . ( J Manipulative Physiol Ther 2000;23:239 - 45 ) STUDY DESIGN A prospect i ve , cross-sectional study of the correlation between postoperative computed tomography findings and patients ' clinical outcomes approximately 4 years after laminectomy for lumbar spinal stenosis . OBJECTIVES To evaluate clinical and radiologic characteristics and their relation to each other . SUMMARY OF BACKGROUND DATA The goal of surgical management for lumbar spinal stenosis is to decompress the stenotic area determined in radiologic examinations to relieve pressure on the neurovascular structures . However , the success of this decompression very rarely has been confirmed by postoperative radiologic imaging or compared with clinical outcome . METHODS Postoperative computed tomography was performed on 191 patients . The findings were classified as " no stenosis , " " central stenosis , " " lateral stenosis , " or " central -lateral stenosis . " Postoperative instability of the lumbar spine was investigated by functional radiography . Clinical status was assessed by clinical examination . Subjective disability was assessing using the Oswestry question naire , and severity of pain using the visual analog scale . Walking capacity was evaluated by the tread-mill test . RESULTS Radiologic studies revealed postoperative stenosis  in 123 patients ( 64 % ) . Small differences between the computed tomography groups were shown for the Oswestry score , but not for walking distance . Clinical signs , severity of pain , and radiologic instability were very similar for all computed tomography groups . CONCLUSIONS Postoperative radiologic stenosis was very common in patients operated on for lumbar spinal stenosis , but this did not correlate with clinical outcome . The clinician must be cautious when reconciling clinical symptoms and signs with postoperative computed tomography findings in patients operated on for lumbar spinal stenosis STUDY DESIGN A double-blind , r and omized controlled trial of a novel educational booklet compared with a traditional booklet for patients seeking treatment in primary care for acute or recurrent low back pain . OBJECTIVE To test the impact of a novel educational booklet on patients ' beliefs about back pain and functional outcome . SUMMARY OF BACKGROUND DATA The information and advice that health professionals give to patients may be important in health care intervention , but there is little scientific evidence of their effectiveness . A novel patient educational booklet , The Back Book , has been developed to provide evidence -based information and advice consistent with current clinical guidelines . METHODS One hundred sixty-two patients were given either the experimental booklet or a traditional booklet . The main outcomes studied were fear-avoidance beliefs about physical activity , beliefs about the inevitable consequences of back trouble , the Rol and Disability Question naire , and visual analogue pain scales . Postal follow-up response at 1 year after initial treatment was 78 % . RESULTS Patients receiving the experimental booklet showed a statistically significant greater early improvement in beliefs which was maintained at 1 year . A greater proportion of patients with an initially high fear-avoidance beliefs score who received the experimental booklet had clinical ly important improvement in fear-avoidance beliefs about physical activity at 2 weeks , followed by a clinical ly important improvement in the Rol and Disability Question naire score at 3 months . There was no effect on pain . CONCLUSION This trial shows that carefully selected and presented information and advice about back pain can have a positive effect on patients ' beliefs and clinical outcomes , and suggests that a study of clinical ly important effects in individual patients may provide further insights into the management of low back pain Study Design . A prospect i ve cohort study of patients with subacute occupational back pain . Objectives . To study the relation between a marketed opto‐electric device measuring trunk kinematics , a widely used specific functional capacity question naire , and work status in back pain patients , and to assess the responsiveness to change in work status of the opto‐electric device and the question naire . Summary of Background Data . Several instruments have been developed to evaluate the functional capacities of patients with back pain , but the relation between these instruments and work status has rarely been studied . Methods . The relation between the opto‐electric device , the question naire , and work status in patients with back pain was evaluated . The study population was a prospect i ve cohort of patients with subacute back pain who were absent from regular work for more than 4 weeks . All data were compiled blindly on the same day , at study entry ( 4 weeks after work accident ) , and at 12 , 24 , and 52 weeks after the work accident . The validity of the question naire and opto‐electric device scores was assessed with partial correlation analyses , st and ardized response mean , logistic regression analyses , and receiver operating characteristics curves . Results . The correlation between the question naire and opto‐electric device scores was low . The question naire scores were significantly related to work status , but the opto‐electric device scores were not . The question naire was responsive to change in work status , whereas the opto‐electric device was not . Conclusions . The opto‐electric device scores were not related to either functional capacity scores ( question naire ) or work status in patients with low back pain , and the opto‐electric device was not responsive to change in work status . Conversely , the question naire was related to work status and was responsive to change in work status OBJECTIVE Previous studies have shown that cortical-evoked potentials on magnetic stimulation of muscles are influenced by muscle contraction , vibration , and muscle spasm . This study was carried out to determine whether these potentials correlate with palpatory muscle spasm , patient symptoms , and disability in patients with low back pain . METHODS A prospect i ve observational study was performed on 13 subjects with a history of low back pain visiting an orthopedic hospital-based clinic . Patients were screened for serious pathologic conditions by an orthopedic surgeon . The patients were then evaluated for the presence of muscle spasm by one of the investigators who was blinded to the results of the evoked potential studies . Patients were asked to complete a  low back pain visual analogue scale ( VAS ) and a Rol and -Morris Activity Scale ( RMAS ) . Cortical-evoked potentials were recorded with a magnetic stimulator placed over the lumbar paraspinal muscles with the patient in the prone position . The palpatory examination , VAS , RMAS , and the cortical potentials were repeated after 2 weeks of therapy commonly used to reduce muscle spasm . RESULTS The patients demonstrated a significant decrease in low back pain VAS and RMAS scores after treatment compared with before treatment . There was a reduction in the amount of palpatory muscle spasm in 11 of 13 cases . The cortical potentials before treatment were attenuated compared with previously reported controls and showed a significant increase before and after treatment in the amplitude of these potentials with multivariate analysis of variance . There was significant correlation between the changes in cortical potentials after treatment and the changes noted in paraspinal muscle spasm and VAS and RMAS scores . CONCLUSIONS This study confirms the previous report that the amplitude of cerebral-evoked potentials on magnetic stimulation of paraspinal muscles is depressed in the presence of palpable muscle spasm . The close correlation among these potentials , paraspinal muscle spasm , and clinical symptoms suggests that the measurement of muscle activity may be more important in the assessment of low back pain than is commonly accepted 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 
    Output:
    