***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: OBJECTIVE To establish the short-term effects of lumbar posteroanterior mobilization in patients with low-back pain , compared with a control intervention . DESIGN Self-controlled cross-over design . MAIN OUTCOME MEASURES The force-displacement characteristics of the spine in response to the application of a posteroanterior force , lumbar flexion , and extension range of movement ; pain during flexion , extension , and on worst movement ; pain on posteroanterior loading ; and overall pain relief . PATIENTS Twenty-six patients with nonspecific low-back pain who experienced pain on flexion or extension and whose pain settled quickly after provocation , from a physiotherapy clinic and university campus . METHODS Patients received posteroanterior mobilization and a control intervention in an order that was r and omly allocated . The magnitude of force in treatment dose was selected by the treating physiotherapist . An observer who was blinded to the order of interventions performed all measurements . Outcome measures were recorded before and after each intervention , and change scores were calculated to quantify the effect of the intervention . RESULTS No significant differences were found between the mobilization and control interventions in relation to posteroanterior response or range of movement . The score for pain on worst movement showed significantly greater improvement for the mobilization than for the control procedure . CONCLUSIONS Lumbar posteroanterior mobilization was not observed to produce any objective ly measurable change in the mechanical behavior of the lumbar spine of patients with low-back pain . Improvement in some pain variables was observed in comparison with a control procedure , but this may be due to a placebo effect To comprehend the results of a r and omised controlled trial ( RCT ) , readers must underst and its design , conduct , analysis , and interpretation . That goal can be achieved only through total transparency from authors . Despite several decades of educational efforts , the reporting of RCTs needs improvement . Investigators and editors developed the original CONSORT ( Consoli date d St and ards of Reporting Trials ) statement to help authors improve reporting by use of a checklist and flow diagram . The revised CONSORT statement presented here incorporates new evidence and addresses some criticisms of the original statement . The checklist items pertain to the content of the Title , Abstract , Introduction , Methods , Results , and Discussion . The revised checklist includes 22 items selected because empirical evidence indicates that not reporting this information is associated with biased estimates of treatment effect , or because the information is essential to judge the reliability or relevance of the findings . We intended the flow diagram to depict the passage of participants through an RCT . The revised flow diagram depicts information from four stages of a trial ( enrolment , intervention allocation , follow- up , and analysis ) . The diagram explicitly shows the number of participants , for each intervention group , included in the primary data analysis . Inclusion of these numbers allows the reader to judge whether the authors have done an intention- to-treat analysis . In sum , the CONSORT statement is intended to improve the reporting of an RCT , enabling readers to underst and a trial 's conduct and to assess the validity of its results UNLABELLED Low back pain ( LBP ) is one of the most common medical problems in our society . Increasingly , patients are turning to nonpharmacologic analgesic therapies such as percutaneous electrical nerve stimulation ( PENS ) . We design ed this sham-controlled study to compare the effect of three different frequencies of electrical stimulation on the analgesic response to PENS therapy .  Sixty-eight consenting patients with LBP secondary to degenerative lumbar disc disease were treated with PENS therapy at 4 Hz , alternating 15 Hz and 30 Hz ( 15/30 Hz ) , and 100 Hz , as well as sham-PENS ( 0 Hz ) , according to a r and omized , cross-over study design . Each treatment was administered for a period of 30 min three times per week for 2 wk . The pre- and posttreatment assessment s included the health status survey short form and visual analog scales for pain , physical activity , and quality of sleep . After receiving all four treatments , patients completed a global assessment question naire . The sham-PENS treatments failed to produce changes in the degree of pain , physical activity , sleep quality , or daily intake of oral analgesic medications . In contrast , 4-Hz , 15/30-Hz , and 100-Hz stimulation all produced significant decreases in the severity of pain , increases in physical activity , improvements in the quality of sleep , and decreases in oral analgesic requirements ( P < 0.01 ) . Of the three frequencies , 15/30 Hz was the most effective in decreasing pain , increasing physical activity , and improving the quality of sleep ( P < 0.05 ) . In the global assessment , 40 % of the patients reported that 15/30 Hz was the most desirable therapy , and it was also more effective in improving the patient 's sense of well-being . We conclude that the frequency of electrical stimulation is an important determinant of the analgesic response to PENS therapy . Alternating stimulation at 15-Hz and 30-Hz frequencies was more effective than either 4 Hz or 100 Hz in improving outcome measures in patients with LBP . IMPLICATION S The frequency of electrical stimulation seems to be an important determinant of the analgesic efficacy of percutaneous electrical nerve stimulation . Mixed low- and high-frequency stimulation was more effective than either low or high frequencies alone in the treatment of patients with low back pain Therapeutic trials often attempt to “ blind ” patient and investigator to the true nature of treatments received , reducing the influences of conscious or subconscious prejudices . In drug trials , this is accomplished with placebo tablets , but blinding in trials of physical treatments is more problematic . This issue arose in a clinical trial of transcutaneous electrical nerve stimulation ( TENS ) for patients with chronic low back pain . Several study design features were incorporated to promote blinding : use of sham TENS units visually identical with real units , exclusion of potential subjects with previous TENS experience , avoidance of a crossover design and use of identical visit frequency , instructions and modifications in electrode placement . Subjects were asked not to discuss treatments with the clinicians who performed outcome assessment s. Both patients and clinicians were asked to guess actual treatment assignments at the trial 's end . Every patient in the true TENS group believed the unit was functioning properly , but the degree of certainty varied . In the sham TENS group , 84 % also believed they had functioning units , but their certainty was significantly less than in the active treatment group . Differences in patient perceptions did not affect compliance , as the two groups had similar dropout rates , appointment compliance , days of TENS use and daily duration of TENS use . Clinicians guessed treatments correctly 61 % of the time ( as opposed to 50 % expected by chance ) , again suggesting partial success in blinding . These efforts at blinding may partly explain the negative trial results for TENS efficacy . We conclude that complete blinding is difficult to achieve because of sensory difference in treatment and unintended communication between patient and examiner . Nonetheless , trials of physical treatments can achieve partial blinding with the techniques described here , and the success of blinding can be assessed with simple questions at study completion PURPOSE Herbal medicines are widely used for the treatment of pain , although there is not much information on their effectiveness . This study was design ed to evaluate the effectiveness of willow ( Salix ) bark extract , which is widely used in Europe , for the treatment of low back pain . SUBJECTS AND METHODS We enrolled 210 patients with an exacerbation of chronic low back pain who reported current pain of 5 or more ( out of 10 ) on a visual analog scale . They were r and omly assigned to receive an oral willow bark extract with either 120 mg ( low dose ) or 240 mg ( high dose ) of salicin , or placebo , with tramadol as the sole rescue medication , in a 4-week blinded trial . The principal outcome measure was the proportion of patients who were pain-free without tramadol for at least 5 days during the final week of the study . RESULTS The treatment and placebo groups were similar at baseline in 114 of 120 clinical features . A total of 191 patients completed the study . The numbers of pain-free patients in the last week of treatment were 27 ( 39 % ) of 65 in the group receiving high-dose extract , 15 ( 21 % ) of 67 in the group receiving low-dose extract , and 4 ( 6 % ) of 59 in the placebo group ( P < 0.001 ) . The response in the high-dose group was evident after only 1 week of treatment . Significantly more patients in the placebo group required tramadol ( P < 0.001 ) during each week of the study . One patient suffered a severe allergic reaction , perhaps to the extract . CONCLUSION Willow bark extract may be a useful and safe treatment for low back pain Study Design . Two replicate , 4-week , r and omized , double-blind , placebo-controlled , trials of rofecoxib 25 and 50 mg versus placebo for chronic low back pain . Objectives . To determine the efficacy and safety of two doses of rofecoxib compared to placebo in the treatment of chronic low back pain . Summary of Background Data . Although nonsteroidal anti-inflammatory drugs are commonly prescribed for chronic low back pain , their efficacy is unproven and toxicity can be serious . These studies evaluated the efficacy and tolerability of rofecoxib , a selective COX-2 inhibitor , in the treatment of chronic low back pain . Methods . Patients with chronic low back pain were r and omized 1:1:1 to rofecoxib 25 mg , 50 mg , or placebo once daily . Primary endpoint : Low Back Pain Intensity . Secondary endpoints : Pain Bothersomeness , Global Assessment s of Response to Therapy , Global Assessment of Disease Status , Rol and -Morris Disability Question naire , SF-12 Health Survey , Use of Rescue Acetaminophen , and Discontinuations Due to Lack of Efficacy . Results . Combining both studies , 690 patients were r and omized to placebo ( N = 228 ) ,  rofecoxib 25 mg ( N = 233 ) , or  rofecoxib 50 mg ( N = 229 ) . Mean ( ± SD ) age was 53.4 ( ± 12.9 ) years , pain duration 12.1 ( ± 11.8 ) years , 62.3 % female .  Both rofecoxib groups improved significantly . Mean differences from placebo in pain intensity were −13.50 mm , −13.81 mm ( 25 , 50 mg doses ) respectively ( P < 0.001 ) . Both regimens were superior to placebo in eight of nine secondary endpoints . Fifty mg provided no advantage over 25 mg . Both rofecoxib regimens were well tolerated , although 25 mg had a slightly better safety profile . Conclusions . Rofecoxib significantly  reduced chronic low back pain in adults and was well tolerated Study Design . A r and omized controlled trial . Objectives . To evaluate the efficacy of infliximab , a monoclonal antibody against tumor necrosis factor (TNF)-&agr ; in a r and omized controlled setting . Summary of Background Data . Recently , we obtained encouraging results in an open-label study of infliximab in patients with disc herniation-induced sciatica . Furthermore , the results of experimental studies support the use of infliximab in sciatica . Therefore , we initiated a r and omized , controlled trial ( FIRST II , Finnish Infliximab Related STudy ) to confirm the efficacy of a single infusion of infliximab for sciatic pain . Methods . Inclusion criteria were unilateral moderate to severe sciatic pain with an MRI-confirmed disc herniation concordant with the symptoms and signs of radicular pain . Patients had to be c and i date s for discectomy , as evaluated by an independent orthopedic surgeon . Forty patients were allocated to a single intravenous infusion of either infliximab 5 mg/kg or placebo . Assessment s at baseline and various time points included clinical examination with measurement of straight leg raising restriction ; question naires related to subjective symptoms ( leg and back pain by 100-mm visual analog scale , Oswestry disability ) ; sick leaves ; number of discectomies ; and adverse effects possibly related to treatment . The primary endpoint was a reduction in leg pain from baseline to 12 weeks , which was analyzed using a Mann-Whitney U test and repeated- measures analysis . Results . A significant reduction in leg pain was observed in both groups , with no significant difference between treatment regimens . Similar efficacy was observed between treatment groups for secondary endpoints . Seven patients in each group required surgery . No adverse effects related to treatment were encountered . Conclusions . The results of this r and omized trial do not support the use of infliximab for lumbar radicular pain in patients with disc herniation-induced sciatica Objective Chronic low back pain ( CLBP ) is a widespread ailment . The aim of this study was to assess the efficacy of topiramate in the treatment of CLBP and the changes in anger status and processing , body weight , subjective pain-related disability and health-related quality of life during the course of treatment . Methods We conducted a 10-week , r and omized , double-blind , placebo-controlled study of topiramate in 96 ( 36 women ) patients with CLBP . The subjects were r and omly assigned to topiramate ( n=48 ) or placebo ( n=48 ) . Primary outcome measures were changes on the McGill Pain Question naire , State-Trait Anger Expression Inventory , Oswestry Low Back Pain Disability Question naire and SF-36 Health Survey scales , and in body weight . Results In comparison with the placebo group ( according to the intent-to-treat principle ) , significant changes on the pain rating index of McGill Pain Question naire ( Ps<0.001 ) , State-Trait Anger Expression Inventory Scales ( all 
    Output:
    
The strategy most commonly used to enhance blinding was the provision of structurally equivalent placebos .
Taken together , these results demonstrate that imperfect placebos are common in low back pain trials ; a result suggesting that many trials provide potentially biased estimates of treatment efficacy .