***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: Evidence -based practice involves the use of evidence from systematic review s and r and omised controlled trials , but the extent of this evidence in physiotherapy has not previously been surveyed . The aim of this survey is to describe the quantity and quality of r and omised controlled trials and the quantity of systematic review s relevant to physiotherapy . The Physiotherapy Evidence Data base ( PEDro ) was search ed . The quality of trials was assessed with the PEDro scale . The search identified a total of 2,376 r and omised controlled trials and 332 systematic review s. The first trial was published in 1955 and the first review was published in 1982 . Since that time , the number of trials and review s has grown exponentially . The mean PEDro quality score has increased from 2.8 in trials published between 1955 and 1959 to 5.0 for trials published between 1995 and 1999 . There is a substantial body of evidence about the effects of physiotherapy . However , there remains scope for improvements in the quality of the conduct and reporting of clinical trials BACKGROUND AND PURPOSE Systematic review s and meta-analyses often include an evaluation of the method ological quality of the individual studies that have been included , and are usually conducted by at least 2 individuals . The objective of this study was to assess the method ological quality and reliability of a series of r and omized controlled trials ( RCTs ) of both pharmacological and nonpharmacological interventions by use of the 10-item Physiotherapy Evidence -Based Data base ( PEDro ) Scale . METHODS Two abstract ors independently review ed 81 RCTs assessing a variety of interventions . The Cohen kappa statistic and the intraclass correlation coefficient ( ICC ) were used to assess agreement between abstract ors . RESULTS The average total PEDro scores were 5.94 ( SD=1.43 ) for all studies combined , 6.88 ( SD=1.2 ) for pharmacological studies , and 5.29 ( SD=1.26 ) for nonpharmacological studies . The median score for pharmacological studies was significantly higher than that for nonpharmacological studies ( 7 versus 5 ) . Pair-wise kappa scores ranged from a low of .452 for concealed allocation among drug trials to perfect agreement ( 1.00 ) for r and omization and reporting of results from between-group comparisons . The ICCs associated with the cumulative PEDro score were .91 ( 95 % confidence interval [CI]=.83-.94 ) for all studies , .89 ( 95 % CI=.78-.95 ) for pharmacological studies , and .91 ( 95 % CI=.84-.952 ) for nonpharmacological studies . DISCUSSION AND CONCLUSION The method ological quality for pharmacological interventions was significantly higher than that for nonpharmacological interventions . There was good agreement between raters at an individual item level and in total PEDro scores . A lack of reporting clarity , poor organization of the report , or the failure to include salient details contributed to less-than-perfect agreement between raters The aim of this study was to evaluate the analgesic effect of transcranial direct current stimulation of the motor cortex and techniques of visual illusion , applied isolated or combined , in patients with neuropathic pain following spinal cord injury . In a sham controlled , double-blind , parallel group design , 39 patients were r and omized into four groups receiving transcranial direct current stimulation with walking visual illusion or with control illusion and sham stimulation with visual illusion or with control illusion . For transcranial direct current stimulation , the anode was placed over the primary motor cortex . Each patient received ten treatment sessions during two consecutive weeks . Clinical assessment was performed before , after the last day of treatment , after 2 and 4 weeks follow-up and after 12 weeks . Clinical assessment included overall pain intensity perception , Neuropathic Pain Symptom Inventory and Brief Pain Inventory . The combination of transcranial direct current stimulation and visual illusion reduced the intensity of neuropathic pain significantly more than any of the single interventions . Patients receiving transcranial direct current stimulation and visual illusion experienced a significant improvement in all pain subtypes , while patients in the transcranial direct current stimulation group showed improvement in continuous and paroxysmal pain , and those in the visual illusion group improved only in continuous pain and dysaesthesias . At 12 weeks after treatment , the combined treatment group still presented significant improvement on the overall pain intensity perception , whereas no improvements were reported in the other three groups . Our results demonstrate that transcranial direct current stimulation and visual illusion can be effective in the management of neuropathic pain following spinal cord injury , with minimal side effects and with good tolerability Weak transcranial direct current stimulation ( tDCS ) induces persisting excitability changes in the human motor cortex . These plastic excitability changes are selectively controlled by the polarity , duration and current strength of stimulation . To reveal the underlying mechanisms of direct current (DC)-induced neuroplasticity , we combined tDCS of the motor cortex with the application of Na(+)-channel-blocking carbamazepine ( CBZ ) and the N-methyl-D-aspartate (NMDA)-receptor antagonist dextromethorphan ( DMO ) . Monitored by transcranial magnetic stimulation ( TMS ) , motor cortical excitability changes of up to 40 % were achieved in the drug-free condition . Increase of cortical excitability could be selected by anodal stimulation , and decrease by cathodal stimulation . Both types of excitability change lasted several minutes after cessation of current stimulation . DMO suppressed the post-stimulation effects of both anodal and cathodal DC stimulation , strongly suggesting the involvement of NMDA receptors in both types of DC-induced neuroplasticity . In contrast , CBZ selectively eliminated anodal effects . Since CBZ stabilizes the membrane potential voltage-dependently , the results reveal that after-effects of anodal tDCS require a depolarization of membrane potentials . Similar to the induction of established types of short- or long-term neuroplasticity , a combination of glutamatergic and membrane mechanisms is necessary to induce the after-effects of tDCS . On the basis of these results , we suggest that polarity-driven alterations of resting membrane potentials represent the crucial mechanisms of the DC-induced after-effects , leading to both an alteration of spontaneous discharge rates and to a change in NMDA-receptor activation Although electrical stimulation of the pre central gyrus ( MCS ) is emerging as a promising technique for pain control , its mechanisms of action remain obscure , and its application largely empirical . Using positron emission tomography ( PET ) we studied regional changes in cerebral flood flow ( rCBF ) in 10 patients undergoing motor cortex stimulation for pain control , seven of whom also underwent somatosensory evoked potentials and nociceptive spinal reflex recordings .  The most significant MCS-related increase in rCBF concerned the ventral-lateral thalamus , probably reflecting cortico-thalamic connections from motor areas . CBF increases were also observed in medial thalamus , anterior cingulate/orbitofrontal cortex , anterior insula and upper brainstem ; conversely , no significant CBF changes appeared in motor areas beneath the stimulating electrode . Somatosensory evoked potentials from SI remained stable during MCS , and no rCBF changes were observed in somatosensory cortex during the procedure . Our results suggest that descending axons , rather than apical dendrites , are primarily activated by MCS , and highlight the thalamus as the key structure mediating functional MCS effects . A model of MCS action is proposed , whereby activation of thalamic nuclei directly connected with motor and premotor cortices would entail a cascade of synaptic events in pain-related structures receiving afferents from these nuclei , including the medial thalamus , anterior cingulate and upper brainstem . MCS could influence the affective-emotional component of chronic pain by way of cingulate/orbitofrontal activation , and lead to descending inhibition of pain impulses by activation of the brainstem , also suggested by attenuation of spinal flexion reflexes . In contrast , the hypothesis of somatosensory cortex activation by MCS could not be confirmed by our results Abstract Past evidence has shown that motor cortical stimulation with invasive and non‐invasive brain stimulation is effective to relieve central pain . Here we aim ed to study the effects of another , very safe technique of non‐invasive brain stimulation – transcranial direct current stimulation ( tDCS ) – on pain control in patients with central pain due to traumatic spinal cord injury . Patients were r and omized to receive sham or active motor tDCS ( 2 mA , 20 min for 5 consecutive days ) . A blinded evaluator rated the pain using the visual analogue scale for pain , Clinician Global Impression and Patient Global Assessment . Safety was assessed with a neuropsychological battery and confounders with the evaluation of depression and anxiety changes . There was a significant pain improvement after active anodal stimulation of the motor cortex , but not after sham stimulation . These results were not confounded by depression or anxiety changes . Furthermore , cognitive performance was not significantly changed throughout the trial in both treatment groups . The results of our study suggest that this new approach of cortical stimulation can be effective to control pain in patients with spinal cord lesion . We discuss potential mechanisms for pain amelioration after tDCS , such as a secondary modulation of thalamic nuclei activity & NA ; A longitudinal cohort study of 100 people with traumatic spinal cord injury ( SCI ) was performed to determine the prevalence and severity of different types of pain ( musculoskeletal , visceral , neuropathic at‐level , neuropathic below‐level ) at 5 years following SCI . Prospect i ve data on the characteristics of pain up to 6 months following injury had been collected previously and allowed comparisons between the presence of pain at different time points . In addition , we sought to determine the relationship between the presence of pain and physical factors related to the injury such as level of lesion , completeness and clinical SCI syndrome . We also obtained information regarding mood , global self‐rated health and the impact of pain on function . Of the 100 subjects in the original cohort , 73 were available for follow up . When all types of pain were included , 59 of the 73 subjects ( 81 % ) reported the presence of pain . Musculoskeletal pain was the most common type of pain experienced and was present in 43 subjects ( 59 % ) , at‐level neuropathic pain was present in 30 subjects ( 41 % ) , below‐level neuropathic pain was present in 25 subjects ( 34 % ) and visceral pain was present in four subjects ( 5 % ) . Overall , 58 % reported their pain as severe or excruciating and those with visceral pain were most likely to rate their pain in these categories . There was no relationship between the presence of pain overall and level or completeness of lesion , or type of injury . However , tetraplegics were more likely to report below‐level neuropathic pain . This study prospect ively demonstrates the differing time courses of different types of pain over the first 5 years following SCI . There was a strong correlation between the presence of both types of neuropathic pain at 5 years and earlier time points but both visceral pain and musculoskeletal pain demonstrated a poor correlation between time points . Chronic visceral pain occurs in a small percentage of patients and does not correlate with the presence of visceral pain early following injury . Those with neuropathic pain early following their injury are likely to continue to experience ongoing pain and the pain is likely to be severe . In contrast , chronic musculoskeletal pain is more common but less likely to be severe and can not be predicted by the presence of pain in the first 6 months following injury UNLABELLED Neuropathic pain in patients with MS is frequent and is associated with a great interference with daily life activities . In the present study , we investigated whether anodal transcranial direct current stimulation ( tDCS ) may be effective in reducing central chronic pain in MS patients . Patients received sham tDCS or real tDCS in a 5-day period of treatment in a r and omized , double blind , sham-controlled study . Pain was measured using visual analog scale ( VAS ) for pain and the short form McGill question naire ( SF-MPQ ) . Quality of life was measured using the Multiple Sclerosis Quality of Life-54 scale ( MSQoL-54 ) . Depressive symptoms and anxiety were also evaluated as confounding factors using the Beck Depression Inventory ( BDI ) and VAS for anxiety . Evaluations were performed at baseline , immediately after the end of treatment , and once a week during a 3-week follow-up period . Following anodal but not sham tDCS over the motor cortex , there was a significant pain improvement as assessed by VAS for pain and McGill question naire , and of overall quality of life . No depression or anxiety changes were observed . Our results show that anodal tDCS is able to reduce pain-scale scores in MS patients with central chronic pain and that this effect outlasts the period of stimulation , leading to long-lasting clinical effects . PERSPECTIVE This article presents a new , noninvasive therapeutic approach to chronic , central neuropathic pain in multiple sclerosis , poorly responsive to current conventional medications . tDCS is known to cause long-lasting changes of neuronal excitability at the site of stimulation and in the connected areas in healthy subjects . This led us to hypothesize that pain decrease may be the result of functional plastic changes in brain structures involved in the pathogenesis of chronic neuropathic pain OBJECTIVE Transcranial direct current stimulation ( tDCS ) has demonstrated efficacy for reducing neuropathic pain , but the respective mechanisms remain largely unknown . The current study tested the hypothesis that pain reduction with tDCS is associated with an increase in the peak frequency spectrum density in the theta-alpha range . METHODS Twenty patients with spinal cord injury and bilateral neuropathic pain received single sessions of both sham and anodal t 
    Output:
    
Conclusion : Meta-analytic results indicate a moderate effect of tDCS in reducing neuropathic pain among individuals with SCI ; however , the effect was not maintained at follow-up .
Several factors were implicated in the effectiveness of tDCS  in reducing pain .