***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 
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    ***EXAMPLES*** 
    Input: & NA ;  Pain intensity is frequently measured on an 11‐point pain intensity numerical rating scale ( PI‐NRS ) , where 0=no pain and 10=worst possible pain . However , it is difficult to interpret the clinical importance of changes from baseline on this scale ( such as a 1‐ or 2‐point change ) . To date , there are no data driven estimates for clinical ly important differences in pain intensity scales used for chronic pain studies . We have estimated a clinical ly important difference on this scale by relating it to global assessment s of change in multiple studies of chronic pain . Data on 2724 subjects from 10 recently completed placebo‐controlled clinical trials of pregabalin in diabetic neuropathy , postherpetic neuralgia , chronic low back pain , fibromyalgia , and osteoarthritis were used . The studies had similar design s and measurement instruments , including the PI‐NRS , collected in a daily diary , and the st and ard seven‐point patient global impression of change ( PGIC ) , collected at the endpoint . The changes in the PI‐NRS from baseline to the endpoint were compared to the PGIC for each subject . Categories of ‘ much improved ’ and ‘ very much improved ’ were used as determinants of a clinical ly important difference and the relationship to the PI‐NRS was explored using graphs , box plots , and sensitivity/specificity analyses . A consistent relationship between the change in PI‐NRS and the PGIC was demonstrated regardless of study , disease type , age , sex , study result , or treatment group . On average , a reduction of approximately two points or a reduction of approximately 30 % in the PI‐NRS represented a clinical ly important difference . The relationship between percent change and the PGIC was also consistent regardless of baseline pain , while higher baseline scores required larger raw changes to represent a clinical ly important difference . The application of these results to future studies may provide a st and ard definition of clinical ly important improvement in clinical trials of chronic pain therapies . Use of a st and ard outcome across chronic pain studies would greatly enhance the comparability , validity , and clinical applicability of these studies CONTEXT Low back pain is a frequent and costly health problem . Prevention of low back pain is important both for the individual patient and from an economic perspective . OBJECTIVE To assess the efficacy of lumbar supports and education in the prevention of low back pain in industry . DESIGN A r and omized controlled trial with a factorial design . SETTING The cargo department of an airline company in the Netherl and s. PARTICIPANTS A total of 312 workers were r and omized , of whom 282 were available for the 6-month follow-up . INTERVENTIONS Subjects were r and omly assigned to 4 groups : ( 1 ) education ( lifting instructions ) and lumbar support , ( 2 ) education , ( 3 ) lumbar support , and ( 4 ) no intervention . Education consisted of 3 group sessions on lifting techniques with a total duration of 5 hours . Lumbar supports were recommended to be used during working hours for 6 months . MAIN OUTCOME MEASURES Low back pain incidence and sick leave because of back pain during the 6-month intervention period . RESULTS Compliance with wearing the lumbar support at least half the time was 43 % . In the 282 subjects for whom data were available , no statistically significant differences in back pain incidence ( 48 [ 36 % ] of 134 with lumbar support vs 51 [ 34 % ] of 148 without , P=.81 ) or in sick leave because of low back pain ( mean , 0.4 days per month with lumbar support vs 0.4 days without , P=.52 ) were found among the intervention groups . In a subgroup of subjects with low back pain at baseline , lumbar supports reduced the number of days with low back pain per month ( median , 1.2 vs 6.5 days per month ; P=.03 ) . CONCLUSIONS Overall , lumbar supports or education did not lead to a reduction in low back pain incidence or sick leave . The results of the subgroup analysis need to be confirmed by future research . Based on our results , the use of education or lumbar supports can not be recommended in the prevention of low back pain in industry The aims of this study were to assess the compliance of home care workers with low back pain ( LBP ) in using a lumbar support , to establish the benefit experienced from the support , and to determine the predictive factors for that compliance and benefit . Only home care workers who had LBP at the start of the study or who had experienced at least two episodes of LBP in the 12 months prior to the study could apply for participation . The study consisted of two phases . In phase I ( the first week of the study ) , workers used the lumbar support each working day . In phase II ( the following 6 months ) , subjects were instructed to use the lumbar support only on those working days when they experienced LBP . Weekly question naires were used to measure compliance ; monthly question naires were used to measure the benefit experienced .  Fifty-nine workers participated in the study . Overall , they scored their perceived benefit from the lumbar support as 7 on a scale of 0 - 10 , and 61 - 81 % of the workers were compliant . Multiple linear regression analysis showed that the best predictor for experienced benefit is the degree of confidence in expected pain reduction due to the lumbar support , measured after phase I ( R(2 ) = 0.70 ) . Multiple logistic analysis showed that the best predictor for compliance is the extent to which subjects consider they can influence their own health status ( R(2 ) = 0.49 ) . Because both the benefit experienced and the compliance rate were substantial , the use of lumbar supports by home care workers with LBP seems feasible . However , we can not recommend extensive use of lumbar supports in home care workers with LBP based solely on the results of the present study . First , there is a clear need for a r and omized clinical trial on this topic Abstract . When measuring treatment effect in chronic low back pain with multi-item outcome instruments , it is necessary , both for clinical decision-making and research purpose s , to underst and the clinical importance of the outcome scores . The aims of the present study were three-fold . Firstly , it aim ed to estimate the minimal clinical ly important difference of three multi-item outcome instruments ( the Oswestry Disability Index , the General Function Score and the Zung Depression Scale )  and of the  visual analogue scale ( VAS ) of back pain .  Secondly , it aim ed to estimate the error of measurement of these instruments ; and its third aim was to describe the clinical meaning of score change . The study population consisted of 289 patients treated surgically or non-surgically in a r and omised controlled trial . The minimal clinical ly important difference was estimated with patient global assessment as the external criterion . It was compared with the st and ard error of measurement of the instruments . The individual items of the instruments were compared for score changes related to improvement and deterioration . The st and ard error of measurement of the Oswestry Disability Index , the General Function Score and the Zung Depression Scale was 4 , 6 and 3 units , respectively . The 95 % tolerance interval was 10 , 16 and 8 units , respectively . The minimal clinical ly important difference was 10 , 12 and 8–9 units , respectively , thus not significantly exceeding the tolerance interval . The minimal clinical ly important difference of VAS back pain was 18–19 units , well exceeding the 95 % tolerance interval , which was 15 units . Improvement after treatment for chronic low back pain tends to occur to a greater extent in sleep disturbance , ability to do usual things and psychological irritability , but to a lesser extent in the ability to sit , st and and lift . We conclude that the VAS of back pain is responsive enough to detect the minimal clinical ly important difference , whereas the smallest acceptable score changes of the Oswestry Disability Index , the General Function Score and the Zung Depression Scale may require an increase to exceed the 95 % tolerance interval when used for clinical decision making and for power calculation . Despite improvement after treatment , the ability to sit , st and and lift , remain notable problems The purpose of this study was to vali date the changes in acute pain measurement scales that are most strongly associated with a patient-determined indicator of clinical importance . Measures of pain intensity and pain relief are commonly used outcomes in therapeutic clinical trials . Recent studies of the properties of acute pain measures have provided data defining the cut-off points that are best associated with clinical ly important differences . Validation of these findings in another clinical trial data set is important . Data were obtained from the titration phase of a recently conducted r and omized controlled clinical trial of oral transmucosal fentanyl citrate ( OTFC ) , which compared OTFC to immediate release morphine sulfate ( MSIR ) for the treatment of cancer-related acute breakthrough pain .  Changes in pain intensity and pain relief were recorded every 15 minutes for 60 minutes and global medication performance recorded at the end of each study pain episode . At any titration step , if the patient felt that the first dose of the study medication did not provide adequate relief within 30 minutes , an additional rescue medication could be taken . To find the level of each pain scale best associated with this measure of the adequacy of pain relief , the calculated sensitivity , specificity , and accuracy for different cut-off points of the measured pain scales were compared to whether or not the patient needed rescue medication . The overall ability of the pain measures to discriminate episodes for which a rescue was not needed was calculated using area under the receiver operating characteristics ( ROC ) curves . Data were analyzed from 134 OTFC-naive patients who collected data on 1307 episodes of breakthrough pain . Using the criteria of a balanced sensitivity and specificity , the best cut-off points were determined to be : 33 % for the percent pain intensity difference ; > or = 2 for the raw pain intensity difference on a 0 - 10 numeric rating scale ; > or = 2 ( i.e. , moderate or better ) for pain relief ; > or = 33 % for the percent maximum total pain relief ; and > or = 2 ( good or better ) for global medication performance . ROC area under the curve ranged from 0.839 to 0.862 for each of the pain measures listed above , calculated at 60 minutes . These data indicate that the pain scale cut-off points that are best associated with a patient-derived measure of a clinical ly important difference closely approximate those found in an earlier study . ROC analysis provided evidence that the overall pain measures were strongly associated with not requiring an " additional dose of rescue medication . " Thus , the cut-off points determined for these pain scales provide a good surrogate measure of a patient-determined clinical ly important response . This provides support for the usefulness of these values in future clinical trials of pain therapy The purpose of this multicenter prospect i ve cohort study was to assess personal and job-related factors as determinants of incidence of reported  back injuries among nurses . The study population included 5,649 nurses who were surveyed by question naire  and then observed for a 12-month study period . An annual injury rate of 4.9 % was observed . Four factors were found to be significant ( P less than .01 ) predictors of back injury . All four factors -- service area , lifting , job category , and previously reported back injury -- maintain significance when a forward stepping model of logistic regression is applied . The adjusted odds ratios observed are 4.26 for service areas where lifting occurs most as compared with areas where lifting occurs least ; 2.19 for daily lifters v light , occasional , and nonlifters ; 1.77 for nursing aides v registered nurses and supervisory personnel ; and 1.73 for individuals who have previously reported back injury v those who have not reported previous injury . These findings strongly suggest that job-related rather than personal characteristics are the major predictors of back injury in nurses This study was design ed to determine the effect of multimodal intervention and the prevention of back injury , and to evaluate the adverse side effects of using a lumbosacral corset in the workplace . Subjects were 90 male warehouse workers r and omly selected from over 800 employees at a grocery distribution center . Subjects were assigned to three groups : true controls , no back school , no brace orthoses ; back school only ; and back school plus wearing a custom molded lumbosacral orthosis . Comparisons of pre-testing and 6-month follow-up posttesting for abdominal strength , cognitive data , work injury incidence and productivity and use of health care services were evaluated . Controls and training-only group showed no changes in strength productivity or lost time . Orthoses and training-group showed no changes in strength productivity or accident rate ; however , they showed substantially less lost time . This study supports the concept of using education and prophylactic bracing to prevent back injury and reduce time loss . It appears that the use of intermittent prophylactic bracing has no adverse affects on abdominal muscle strength and may contribute to decreased lost time from work injuries Abstract Objective : To assess the impact of h and ling patients and indicators of individual susceptibility on risk of  low back pain in nurses . Design : Prospect i ve cohort study with follow up by repeated self administered question naires every three months over two years . Setting : NHS university hospitals trust . Subjects : 961 female nurses who had been free from low back pain for at least one month at the time of completing a baseline question naire .  Main outcome measures : Incidence of new low back pain during follow up and of pain leading to absence from work . Results : Of 838 women who provided data suitable for analysis , 322 ( 38 % ) developed low back pain during follow up ( mean 18.6 months ) , including 93 ( 11 % ) whose pain led to absence from work . The strongest predictor of new low back pain was earlier history of the symptom , and risk was particularly high if previous pain had lasted for over a month in total and had occurred within the 12 months before entry to the study ( incidence during follow up 66 % ) . Frequent low mood at baseline was strongly associated with subsequent absence from work for back pain ( odds ratio 3.4 ; 95 % confidence interval 1.4 to 8.2 ) . After adjustment for earlier history of back pain and other potential confounders , risk was higher in nurses who reported frequent manual transfer of patients between bed and chair , manual repositioning of patients on the bed , and lifting patients in or out of the bath with a hoist . Conclusions : Of the indic 
    Output:
    
Implication Adding lumbar supports to instruction on healthy work habits may decrease low back pain recurrence , but not absenteeism , among workers with previous low back pain .
Recent systematic review s of the sparse evidence on lumbar supports ( 6 , 7 ) concluded that no evidence exists for the effectiveness of  lumbar supports  in the primary prevention of low back pain in the workplace , but 2 of the 4 included r and omized , controlled trials ( 8 , 9 ) reported that lumbar supports might be effective in workers with a history of low back pain ( secondary prevention ) .
In cohort studies , a history of low back pain proved to be a strong predictor for the incidence of new episodes of low back pain ( 1012 ) .
Home care workers with a history of low back pain may therefore be well suited to secondary preventive measures .