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: Low back pain ( LBP ) is the second greatest cause of disability in the USA.1 USA data supports that in spite of an enormous increase in the health re sources spent on LBP disorders , the disability relating to them continues to increase.2 The management of LBP is underpinned by the exponential increase in the use of physical therapies , opiod medications , spinal injections as well as disc replacement and fusion surgery.2 This is maintained by the underlying belief that LBP is fundamentally a patho-anatomical disorder and should be treated within a biomedical model.1 This is in spite of calls over a number of years to adopt a bio-psycho-social approach , and evidence that only 8–15 % of patients with LBP have an identified patho-anatomical diagnosis , result ing in the majority being diagnosed as having non-specific LBP.3 Of this population , a small but significant group becomes chronic and disabled , labelled non-specific chronic low back pain ( NSCLBP ) , consuming a disproportionate amount of healthcare re sources .4 1 . Over the past decade , the traditional biomedical view of LBP has been greatly challenged . This is a result of : the failure of simplistic single-dimensional therapies to show large effects in patients with NSCLBP5–8 ; 2 . the results of clinical trials testing commonly prescribed interventions demonstrating that no management approaches are clearly superior5–7 9 ; 3 . the stories of NSCLBP patients relating their own ongoing pain experiences of multiple failed treatments , conflicting diagnoses , lost hope and ongoing suffering10 ; 4 . the indisputable evidence supporting the multidimensional nature of NSCLBP as a disorder , where disability levels are more closely associated with cognitive and behavioural aspects of pain rather than sensory and biomedical ones11 12 ; 5 . positive outcomes in r and omised controlled trials ( RCTs ) are best predicted by changes in psychological distress , fear avoidance beliefs , self-efficacy in Seated work has been shown to constitute a risk factor for  low-back pain .  This is attributed to the prolonged and monotonous low-level mechanical load imposed by a seated posture . To evaluate the potential health effects with respect to the low back of office chairs with a movable seat and back rest , trunk kinematics , erector spinae EMG , spinal shrinkage and local discomfort were assessed in 10 subjects performing simulated office work .  On three separate occasions subjects performed a 3 h task consisting of word processing , computer-aided design and reading . Three chairs were used , one with a fixed seat and back rest and two dynamic chairs , one with a seat and back rest movable in a fixed ratio with respect to each other , and one with a freely movable seat and back rest .  Spinal shrinkage measurements showed a larger stature gain when working on the two dynamic chairs as compared with working on the chair with fixed seat and back rest . Trunk kinematics and erector spinae EMG were strongly affected by the task performed but not by the chair type . The results imply that dynamic office chairs offer a potential advantage over fixed chairs , but the effects of the task on the indicators of trunk load investigated were more pronounced than the effects of the chair QUESTIONS Does the PEDro scale measure only one construct ie , the method ological quality of clinical trials ? What is the hierarchy of items of the PEDro scale from least to most adhered to ? Is there any effect of year of publication of trials on item adherence ? Are PEDro scale ordinal scores equivalent to interval data ? DESIGN Rasch analysis of two independent sample s of 100 clinical trials from the PEDro data base scored using the PEDro scale . RESULTS Both sample s of PEDro data showed fit to the Rasch model with no item misfit . The  PEDro scale item hierarchy was the same in both sample s , ranging from the most adhered to item r and om allocation , to the least adhered to item therapist blinding . There was no differential item functioning by year of publication . Original PEDro ordinal scores were highly correlated with transformed PEDro interval scores ( r = 0.99 ) . CONCLUSION The PEDro scale is a valid measure of the method ological quality of clinical trials . It is valid to sum PEDro scale item scores to obtain a total score that can be treated as interval level measurement and subjected to parametric statistical analysis Most systematic review s rely substantially on the assessment of the method ological quality of the individual trials . The aim of this study was to obtain consensus among experts about a set of generic core items for quality assessment of r and omized clinical trials ( RCTs ) . The invited participants were experts in the field of quality assessment of RCTs . The initial item pool contained all items from existing criteria lists . Subsequently , we reduced the number of items by using the Delphi consensus technique . Each Delphi round comprised a question naire , an analysis , and a feedback report . The feedback report included staff team decisions made on the basis of the analysis and their justification . A total of 33 international experts agreed to participate , of whom 21 completed all question naires . The initial item pool of 206 items was reduced to 9 items in three Delphi rounds . The final criteria list ( the Delphi list ) was satisfactory to all participants . It is a starting point on the way to a minimum reference st and ard for RCTs on many different research topics . This list is not intended to replace , but rather to be used alongside , existing criteria lists Study Design . Prospect i ve cohort study of r and omly selected Veterans Affairs ( VA ) out patients . Objective . To determine the prevalence of  magnetic resonance imaging ( MRI ) findings in the lumbar spine among persons without current low back pain or sciatica and to examine which findings are related to age or previous back symptoms . Summary of Background Information . Previous studies of patients without low back pain have not explored the possible association of various MRI findings to past symptoms . Methods . We r and omly selected an age-stratified sample of subjects without low back pain in the past 4 months from clinics at a VA hospital . We collected information on demographics , comorbidity , functional status , and quality of life .  MR images were obtained using a st and ardized protocol through each of the five lumbar disc levels . Results . Of 148 subjects , 69 ( 46 % ) had never experienced low back pain .  There were 123 subjects ( 83 % ) with moderate to severe desiccation of one or more discs , 95 ( 64 % ) with one or more bulging discs , and 83 ( 56 % ) with loss of disc height . Forty-eight subjects ( 32 % ) had at least one disc protrusion and 9 ( 6 % ) had one or more disc extrusions . Conclusion . Many MR imaging findings have a high prevalence in subjects without low back pain . These findings are therefore of limited diagnostic use . The less common findings of moderate or severe central stenosis , root compression , and extrusions are likely to be diagnostically and clinical ly relevant BACKGROUND CONTEXT It is generally recognized that long periods of sitting can either cause or aggravate lumbar pain . A new , ergonomically design ed chair has a fixed backrest and a motor-driven seat with a horizontal rotary movement in alternating left-right cycles . PURPOSE The objective of this study is to prove superiority of the new technique of passive rotary dynamic sitting for subjects working in a sedentary occupation and suffering from lumbar pain . STUDY DESIGN / SETTING A r and omized , double-blind , multicenter , two-armed study was performed using a parallel group design . PATIENT SAMPLE 280 persons suffering from lumbar pain were matched pairwise and r and omized en bloc . OUTCOME MEASURES The first and second primary endpoints target criteria were the vali date d German version of the Oswestry Disability Index ( ODI ) and the number of days of absence from work ( DA ) attributable to lumbar pain , each based on a blinded 2-year follow-up observation after r and omization of the subjects . METHODS After inclusion in the study anonymization , the prob and s were r and omized to receive either an office chair with a motor-driven seat performing a horizontal rotary movement or a chair of the same design without the rotary seat movement . Before delivery of the chairs , 23 prob and s ( 8.2 % ) withdrew their consent to inclusion in the study without stating reasons . From 12 of the remaining matching partners , 23 new pairs were created at r and om , and the study commenced with 124 pairs . RESULTS A further 27 prob and s ( 9.6 % ) were lost to follow-up during the period up to the final consultation . This made it possible to observe the primary endpoint in 82.5 % of the prob and s. The median ODI in both groups was 53 ( 95 % confidence interval for median difference:-1.5 to 0.5 ; p=.59 ) . Median DA in both groups was 0 ( 95 % confidence interval for median difference:-infinity-+infinity ; p=1.00 ) . CONCLUSIONS Under the test conditions used in this study , passive rotary dynamic sitting was not superior to sitting in a high- quality , ergonomically design ed chair not equipped with a micro-rotation function in patients suffering from lumbar pain This study compared the effects of sitting with portable supports in either a kyphotic or lordotic posture on  low-back and referred pain . Two hundred ten patients with low-back and /or referred pain were r and omly assigned to either a  kyphotic posture or lordotic posture group . The kyphotic and lordotic postures were facilitated by the use of a flat foam cushion or lumbar roll , respectively . Pain location , back pain , and leg pain intensity were assessed over a 24–48-hour period under both st and ardized clinical setting s and general sitting environments . When sitting with a lordotic posture , back and leg pain were significantly reduced and referred pain shifted towards the low back . This study demonstrates that in general sitting environments a lumbar roll results in : 1 ) reductions in back and leg pain ; and 2 ) central ization of pain . These findings do not apply to patients with stenosis or spondylolisthesis , whose symptoms may be aggravated by use of a lumbar roll Study Design . Subjective ratings of discomfort were compared between a fixed lumbar support and lumbar support continuous passive motion ( CPM ) device . Objective . To compare a fixed lumbar support with a lumbar support CPM device during prolonged sitting . Summary of Background Data . To prevent low back pain during prolonged sitting , an inflatable lumbar support CPM has been developed . There are no studies that compare static lumbar support with lumbar CPM using the same pressure in the cushions . Methods . A total of 31 male volunteers without low back pain sat in the same chair for a 2-hour period on each of 3 consecutive days under 3 r and omized test methods : 1 , no lumbar support ; 2 , static lumbar support ; and 3 , lumbar support CPM . Each subject rated low back pain , stiffness , fatigue , and buttock numbness on a visual analog scale ( VAS ) .  Fixed lumbar support and CPM device were compared with a same inflation pressure in the cushion . For 10 subjects , the whole body posture and the pressure distribution changes of the human-seat interface during CPM were evaluated . Results . Compared with no lumbar support , a significant improvement in VAS scores for low back pain , stiffness , and fatigue was obtained with both static lumbar support and with lumbar support CPM ( P < 0.005 ) . A significant ( P < 0.005 ) improvement for buttock numbness was obtained only with lumbar support CPM . There were no statistical differences in all VAS scores between the fixed lumbar support and the CPM device . A forward rotation of the pelvic region was obtained during inflation of the cushion during CPM . Significant differences ( P < 0.05 ) were found between cushion inflation and deflation periods both in contact areas and in the peak pressures at the human-seat interface . Conclusion . There were no statistical differences in the subjective ratings of discomfort between the fixed lumbar support and the CPM device BACKGROUND AND PURPOSE Assessment of the quality of r and omized controlled trials ( RCTs ) is common practice in systematic review s. However , the reliability of data obtained with most quality assessment scales has not been established . This report describes 2 studies design ed to investigate the reliability of data obtained with the Physiotherapy Evidence Data base ( PEDro ) scale developed to rate the quality of RCTs evaluating physical therapist interventions . METHOD In the first study , 11 raters independently rated 25 RCTs r and omly selected from the PEDro data base . In the second study , 2 raters rated 120 RCTs r and omly selected from the PEDro data base , and disagreements were resolved by a third rater ; this generated a set of individual rater and consensus ratings . The process was repeated by independent raters to create a second set of individual and consensus ratings . Reliability of ratings of PEDro scale items was calculated using multirater kappas , and reliability of the total ( summed ) score was calculated using intraclass correlation coefficients ( ICC [ 1,1 ] ) . RESULTS The kappa value for each of the 11 items ranged from.36 to.80 for individual assessors and from.50 to.79 for consensus ratings generated by groups of 2 or 3 raters . The ICC for the total score was.56 ( 95 % confidence interval=.47-.65 ) for ratings by individuals , and the ICC for consensus ratings was.68 ( 95 % confidence interval=.57-.76 ) . DISCUSSION AND CONCLUSION The reliability of ratings of PEDro scale items varied from " fair " to " substantial , " and the reliability of the total PEDro score was " fair " to " good . Abstract In this study the effect of dynamic stimuli on  low back pain during prolonged sitting was investigated . The pain experience of two groups of 60 subjects with aspecific low back pain was recorded . All subjects were investigated on pain behaviour by the Multidimensional Pain Inventory ( MPI ) and pain was measured on an open visual analogue scale ( VAS ) . During sitting , one group received dynamic stimuli that were generated by alternating rotations in the horizontal plane of the seat of the chair , with back 
    Output:
    
agent
The results suggest there is currently no evidence to support the use of dynamic sitting as a st and -alone approach in the management of LBP .
Overall , the evidence suggests that dynamic sitting approaches are not effective as a st and -alone management approach for LBP
***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: Low back pain ( LBP ) is the second greatest cause of disability in the USA.1 USA data supports that in spite of an enormous increase in the health re sources spent on LBP disorders , the disability relating to them continues to increase.2 The management of LBP is underpinned by the exponential increase in the use of physical therapies , opiod medications , spinal injections as well as disc replacement and fusion surgery.2 This is maintained by the underlying belief that LBP is fundamentally a patho-anatomical disorder and should be treated within a biomedical model.1 This is in spite of calls over a number of years to adopt a bio-psycho-social approach , and evidence that only 8–15 % of patients with LBP have an identified patho-anatomical diagnosis , result ing in the majority being diagnosed as having non-specific LBP.3 Of this population , a small but significant group becomes chronic and disabled , labelled non-specific chronic low back pain ( NSCLBP ) , consuming a disproportionate amount of healthcare re sources .4 1 . Over the past decade , the traditional biomedical view of LBP has been greatly challenged . This is a result of : the failure of simplistic single-dimensional therapies to show large effects in patients with NSCLBP5–8 ; 2 . the results of clinical trials testing commonly prescribed interventions demonstrating that no management approaches are clearly superior5–7 9 ; 3 . the stories of NSCLBP patients relating their own ongoing pain experiences of multiple failed treatments , conflicting diagnoses , lost hope and ongoing suffering10 ; 4 . the indisputable evidence supporting the multidimensional nature of NSCLBP as a disorder , where disability levels are more closely associated with cognitive and behavioural aspects of pain rather than sensory and biomedical ones11 12 ; 5 . positive outcomes in r and omised controlled trials ( RCTs ) are best predicted by changes in psychological distress , fear avoidance beliefs , self-efficacy in Seated work has been shown to constitute a risk factor for  low-back pain .  This is attributed to the prolonged and monotonous low-level mechanical load imposed by a seated posture . To evaluate the potential health effects with respect to the low back of office chairs with a movable seat and back rest , trunk kinematics , erector spinae EMG , spinal shrinkage and local discomfort were assessed in 10 subjects performing simulated office work .  On three separate occasions subjects performed a 3 h task consisting of word processing , computer-aided design and reading . Three chairs were used , one with a fixed seat and back rest and two dynamic chairs , one with a seat and back rest movable in a fixed ratio with respect to each other , and one with a freely movable seat and back rest .  Spinal shrinkage measurements showed a larger stature gain when working on the two dynamic chairs as compared with working on the chair with fixed seat and back rest . Trunk kinematics and erector spinae EMG were strongly affected by the task performed but not by the chair type . The results imply that dynamic office chairs offer a potential advantage over fixed chairs , but the effects of the task on the indicators of trunk load investigated were more pronounced than the effects of the chair QUESTIONS Does the PEDro scale measure only one construct ie , the method ological quality of clinical trials ? What is the hierarchy of items of the PEDro scale from least to most adhered to ? Is there any effect of year of publication of trials on item adherence ? Are PEDro scale ordinal scores equivalent to interval data ? DESIGN Rasch analysis of two independent sample s of 100 clinical trials from the PEDro data base scored using the PEDro scale . RESULTS Both sample s of PEDro data showed fit to the Rasch model with no item misfit . The  PEDro scale item hierarchy was the same in both sample s , ranging from the most adhered to item r and om allocation , to the least adhered to item therapist blinding . There was no differential item functioning by year of publication . Original PEDro ordinal scores were highly correlated with transformed PEDro interval scores ( r = 0.99 ) . CONCLUSION The PEDro scale is a valid measure of the method ological quality of clinical trials . It is valid to sum PEDro scale item scores to obtain a total score that can be treated as interval level measurement and subjected to parametric statistical analysis Most systematic review s rely substantially on the assessment of the method ological quality of the individual trials . The aim of this study was to obtain consensus among experts about a set of generic core items for quality assessment of r and omized clinical trials ( RCTs ) . The invited participants were experts in the field of quality assessment of RCTs . The initial item pool contained all items from existing criteria lists . Subsequently , we reduced the number of items by using the Delphi consensus technique . Each Delphi round comprised a question naire , an analysis , and a feedback report . The feedback report included staff team decisions made on the basis of the analysis and their justification . A total of 33 international experts agreed to participate , of whom 21 completed all question naires . The initial item pool of 206 items was reduced to 9 items in three Delphi rounds . The final criteria list ( the Delphi list ) was satisfactory to all participants . It is a starting point on the way to a minimum reference st and ard for RCTs on many different research topics . This list is not intended to replace , but rather to be used alongside , existing criteria lists Study Design . Prospect i ve cohort study of r and omly selected Veterans Affairs ( VA ) out patients . Objective . To determine the prevalence of  magnetic resonance imaging ( MRI ) findings in the lumbar spine among persons without current low back pain or sciatica and to examine which findings are related to age or previous back symptoms . Summary of Background Information . Previous studies of patients without low back pain have not explored the possible association of various MRI findings to past symptoms . Methods . We r and omly selected an age-stratified sample of subjects without low back pain in the past 4 months from clinics at a VA hospital . We collected information on demographics , comorbidity , functional status , and quality of life .  MR images were obtained using a st and ardized protocol through each of the five lumbar disc levels . Results . Of 148 subjects , 69 ( 46 % ) had never experienced low back pain .  There were 123 subjects ( 83 % ) with moderate to severe desiccation of one or more discs , 95 ( 64 % ) with one or more bulging discs , and 83 ( 56 % ) with loss of disc height . Forty-eight subjects ( 32 % ) had at least one disc protrusion and 9 ( 6 % ) had one or more disc extrusions . Conclusion . Many MR imaging findings have a high prevalence in subjects without low back pain . These findings are therefore of limited diagnostic use . The less common findings of moderate or severe central stenosis , root compression , and extrusions are likely to be diagnostically and clinical ly relevant BACKGROUND CONTEXT It is generally recognized that long periods of sitting can either cause or aggravate lumbar pain . A new , ergonomically design ed chair has a fixed backrest and a motor-driven seat with a horizontal rotary movement in alternating left-right cycles . PURPOSE The objective of this study is to prove superiority of the new technique of passive rotary dynamic sitting for subjects working in a sedentary occupation and suffering from lumbar pain . STUDY DESIGN / SETTING A r and omized , double-blind , multicenter , two-armed study was performed using a parallel group design . PATIENT SAMPLE 280 persons suffering from lumbar pain were matched pairwise and r and omized en bloc . OUTCOME MEASURES The first and second primary endpoints target criteria were the vali date d German version of the Oswestry Disability Index ( ODI ) and the number of days of absence from work ( DA ) attributable to lumbar pain , each based on a blinded 2-year follow-up observation after r and omization of the subjects . METHODS After inclusion in the study anonymization , the prob and s were r and omized to receive either an office chair with a motor-driven seat performing a horizontal rotary movement or a chair of the same design without the rotary seat movement . Before delivery of the chairs , 23 prob and s ( 8.2 % ) withdrew their consent to inclusion in the study without stating reasons . From 12 of the remaining matching partners , 23 new pairs were created at r and om , and the study commenced with 124 pairs . RESULTS A further 27 prob and s ( 9.6 % ) were lost to follow-up during the period up to the final consultation . This made it possible to observe the primary endpoint in 82.5 % of the prob and s. The median ODI in both groups was 53 ( 95 % confidence interval for median difference:-1.5 to 0.5 ; p=.59 ) . Median DA in both groups was 0 ( 95 % confidence interval for median difference:-infinity-+infinity ; p=1.00 ) . CONCLUSIONS Under the test conditions used in this study , passive rotary dynamic sitting was not superior to sitting in a high- quality , ergonomically design ed chair not equipped with a micro-rotation function in patients suffering from lumbar pain This study compared the effects of sitting with portable supports in either a kyphotic or lordotic posture on  low-back and referred pain . Two hundred ten patients with low-back and /or referred pain were r and omly assigned to either a  kyphotic posture or lordotic posture group . The kyphotic and lordotic postures were facilitated by the use of a flat foam cushion or lumbar roll , respectively . Pain location , back pain , and leg pain intensity were assessed over a 24–48-hour period under both st and ardized clinical setting s and general sitting environments . When sitting with a lordotic posture , back and leg pain were significantly reduced and referred pain shifted towards the low back . This study demonstrates that in general sitting environments a lumbar roll results in : 1 ) reductions in back and leg pain ; and 2 ) central ization of pain . These findings do not apply to patients with stenosis or spondylolisthesis , whose symptoms may be aggravated by use of a lumbar roll Study Design . Subjective ratings of discomfort were compared between a fixed lumbar support and lumbar support continuous passive motion ( CPM ) device . Objective . To compare a fixed lumbar support with a lumbar support CPM device during prolonged sitting . Summary of Background Data . To prevent low back pain during prolonged sitting , an inflatable lumbar support CPM has been developed . There are no studies that compare static lumbar support with lumbar CPM using the same pressure in the cushions . Methods . A total of 31 male volunteers without low back pain sat in the same chair for a 2-hour period on each of 3 consecutive days under 3 r and omized test methods : 1 , no lumbar support ; 2 , static lumbar support ; and 3 , lumbar support CPM . Each subject rated low back pain , stiffness , fatigue , and buttock numbness on a visual analog scale ( VAS ) .  Fixed lumbar support and CPM device were compared with a same inflation pressure in the cushion . For 10 subjects , the whole body posture and the pressure distribution changes of the human-seat interface during CPM were evaluated . Results . Compared with no lumbar support , a significant improvement in VAS scores for low back pain , stiffness , and fatigue was obtained with both static lumbar support and with lumbar support CPM ( P < 0.005 ) . A significant ( P < 0.005 ) improvement for buttock numbness was obtained only with lumbar support CPM . There were no statistical differences in all VAS scores between the fixed lumbar support and the CPM device . A forward rotation of the pelvic region was obtained during inflation of the cushion during CPM . Significant differences ( P < 0.05 ) were found between cushion inflation and deflation periods both in contact areas and in the peak pressures at the human-seat interface . Conclusion . There were no statistical differences in the subjective ratings of discomfort between the fixed lumbar support and the CPM device BACKGROUND AND PURPOSE Assessment of the quality of r and omized controlled trials ( RCTs ) is common practice in systematic review s. However , the reliability of data obtained with most quality assessment scales has not been established . This report describes 2 studies design ed to investigate the reliability of data obtained with the Physiotherapy Evidence Data base ( PEDro ) scale developed to rate the quality of RCTs evaluating physical therapist interventions . METHOD In the first study , 11 raters independently rated 25 RCTs r and omly selected from the PEDro data base . In the second study , 2 raters rated 120 RCTs r and omly selected from the PEDro data base , and disagreements were resolved by a third rater ; this generated a set of individual rater and consensus ratings . The process was repeated by independent raters to create a second set of individual and consensus ratings . Reliability of ratings of PEDro scale items was calculated using multirater kappas , and reliability of the total ( summed ) score was calculated using intraclass correlation coefficients ( ICC [ 1,1 ] ) . RESULTS The kappa value for each of the 11 items ranged from.36 to.80 for individual assessors and from.50 to.79 for consensus ratings generated by groups of 2 or 3 raters . The ICC for the total score was.56 ( 95 % confidence interval=.47-.65 ) for ratings by individuals , and the ICC for consensus ratings was.68 ( 95 % confidence interval=.57-.76 ) . DISCUSSION AND CONCLUSION The reliability of ratings of PEDro scale items varied from " fair " to " substantial , " and the reliability of the total PEDro score was " fair " to " good . Abstract In this study the effect of dynamic stimuli on  low back pain during prolonged sitting was investigated . The pain experience of two groups of 60 subjects with aspecific low back pain was recorded . All subjects were investigated on pain behaviour by the Multidimensional Pain Inventory ( MPI ) and pain was measured on an open visual analogue scale ( VAS ) . During sitting , one group received dynamic stimuli that were generated by alternating rotations in the horizontal plane of the seat of the chair , with back 
    Output:
    