***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: The objective of this study was to compare the efficacy and tolerability of gabapentin and amitriptyline monotherapy in painful diabetic neuropathy . This was a 12-week , open-label , prospect i ve , r and omized trial . Twenty-five type-II diabetic patients with pain attributed to diabetic neuropathy and a minimum score of 2 on a pain intensity scale ranging from 0 ( no pain ) to 4 ( excruciating pain ) were r and omized to receive either gabapentin , titrated from 1,200 mg/day to a maximum of 2,400 mg/day , or amitriptyline , titrated from 30 mg/day to a maximum of 90 mg/day . Both drugs were titrated over a 4-week period and maintained at the maximum tolerated dose for 8 weeks . The main outcome measures were weekly pain intensity and paresthesia intensity , measured on two categorical scales . Thirteen patients received gabapentin and 12 received amitriptyline .  All 25 patients completed the trial .  Gabapentin produced greater pain reductions than amitriptyline ( mean final scores were 1.9 vs. 1.3 points below baseline scores ; P = 0.026 ) . Decreases in paresthesia scores also were in favor of gabapentin ( 1.8 vs. 0.9 points ; P = 0 . 004 ) . Adverse events were more frequent in the amitriptyline group than in the gabapentin group : they were reported by 11/12 ( 92 % ) and 4/13 ( 31 % ) of patients , respectively ( P = 0.003 ) . Side effects were the main limiting factor preventing dose escalation . Gabapentin produced greater improvements than amitriptyline in pain and paresthesia associated with diabetic neuropathy . Additionally , gabapentin was better tolerated than amitriptyline . Further controlled trials are needed to confirm these preliminary results Twelve patients with severe , painful diabetic neuropathy in the lower extremities were treated with imipramine and placebo in a fixed-dose , double-blind , crossover study of five plus five weeks . Seven patients experienced notable improvement while receiving imipramine and none while receiving placebo . The rating of specific symptoms at the end of each treatment period showed a beneficial effect of imipramine on pain , paresthesia , dysesthesia , numbness , and nocturnal aggravation . The plasma levels of imipramine and its metabolite desipramine were significantly higher in patients who benefited from imipramine treatment BACKGROUND Reports of gabapentin use in diabetic peripheral neuropathy pain stimulate a need for controlled trials to determine its comparative efficacy to the therapeutic st and ard of amitriptyline hydrochloride . OBJECTIVE To determine the efficacy of gabapentin compared with amitriptyline in treating diabetic peripheral neuropathy pain . DESIGN Prospect i ve , r and omized , double-blind , double-dummy , crossover study . SETTING Veterans Affairs San Diego Healthcare System , Ambulatory Care Clinic . PATIENTS Twenty-eight veterans were referred by their primary care providers . Two patients withdrew before r and omization because of no neuropathic pain after washout ; a third withdrew for unexpected surgery that required analgesics . Three patients withdrew because of adverse effects and 1 for protocol violation . INTERVENTIONS Patients with stable glycemic control and neuropathic pain r and omized to 6 weeks of therapy with gabapentin , 900 to 1800 mg/d , or amitriptyline hydrochloride , 25 to 75 mg/d , with a 1-week washout before crossover . MAIN OUTCOME MEASURES Pain relief measured by pain scale with verbal descriptors and global pain score assessment at treatment end . RESULTS Participants and investigators were blinded throughout . Mean dosages were of gabapentin , 1565 mg/d , and of amitriptyline hydrochloride , 59 mg/d . Sixty-five percent of patients reached maximum dose with gabapentin and 54 % with amitriptyline .  Mean score diary analysis showed pain relief with gabapentin and amitriptyline was not significantly different ( P = .26 ) . Global data were obtained from 21 of 25 enrolled patients who completed the study . Moderate or greater pain relief was experienced in 11 ( 52 % ) of 21 patients with gabapentin and 14 ( 67 % ) of 21 patients with amitriptyline . There were no significant period or carry-over effects ( P = .35 ) . CONCLUSIONS Although both drugs provide pain relief , mean pain score and global pain score data indicate no significant difference between gabapentin and amitriptyline . Gabapentin may be an alternative for treating diabetic peripheral neuropathy pain , yet does not appear to offer considerable advantage over amitriptyline and is more expensive . Larger trials are necessary to define gabapentin 's place in treating diabetic peripheral neuropathy pain Objective To evaluate the safety and efficacy of gabapentin and venlafaxine in the treatment of painful diabetic neuropathy in patients whose pain did not improve with gabapentin monotherapy . Methods ( 1 ) A r and omized , double-blind , placebo-controlled , 8-week clinical trial comparing gabapentin versus placebo to define a patient population whose pain did not improve with monotherapy ; ( 2 ) a second 8-week trial comparing gabapentin plus venlafaxine with gabapentin plus placebo ; ( 3 ) a third uncontrolled 8-week trial of patients who did not improve on gabapentin monotherapy and then received venlafaxine in addition to gabapentin .  Results ( 1 ) Gabapentin-treated patients showed statistically significant improvement in pain reduction as well as improvement in quality of life and mood disturbance when compared with placebo-treated patients ; ( 2 ) patients who received gabapentin plus venlafaxine showed significant improvement in pain reduction , mood disturbance , and quality of life when compared with patients treated with gabapentin plus placebo ; ( 3 ) patients who received gabapentin plus venlafaxine showed significant improvement in pain reduction , mood disturbance , and quality of life . Conclusions ( 1 ) Gabapentin is efficacious in the treatment of painful diabetic neuropathy ; ( 2 ) and ( 3 ) in patients who do not respond to gabapentin monotherapy , the addition of venlafaxine is also efficacious CONTEXT Not all research presented at scientific meetings is subsequently published and , even when it is , there may be inconsistencies between these results and what is ultimately printed . Although late-breaking trials sessions are now integrated into several major scientific meetings and the results are often promptly and prominently communicated , no studies have examined the publication fate and degree of consistency between meeting abstract s or presentations and subsequent full-length article publications for r and omized controlled trials ( RCTs ) presented at these sessions . OBJECTIVE To compare RCT abstract s presented in the late-breaking trials session vs other sessions at a major scientific meeting and subsequent full-length publications . DESIGN RCTs were identified by h and search ing abstract proceedings booklets and related Web sites for the American College of Cardiology scientific meetings ( 1999 - 2002 ) . Subsequent full-length articles were identified via electronic data bases . MAIN OUTCOME MEASURES Publication fate and degree of consistency between meeting abstract results and subsequent full-length publication results . RESULTS The 86 late-breaking RCTs were significantly larger ( median , 2737 patients vs 896 ; P<.001 ) , were more likely to be preceded by a published design paper ( 27 [ 31 % ] vs 13 [ 13 % ] ; P = .002 ) , had higher quality scores when eventually published ( mean Jadad score 2.69 vs 2.19 ; P = .01 ) , and were less likely to report favorable results for the intervention than the 100 r and omly chosen comparison RCTs presented in other sessions ( 50 [ 58 % ] vs 75 [ 75 % ] ; P = .01 ; odds ratio 0.46 ; 95 % confidence interval , 0.24 - 0.90 ) . RCTs presented at the late-breaking trials sessions were significantly more likely to be published ( 79 [ 92 % ] vs 69 [ 69 % ] ; P<.001 ) and appeared earlier after presentation ( median 11.5 months vs 22.0 months ; P<.001 ) than RCTs presented in other sessions , an association that persisted even after adjusting for sample size , conclusion of study , and RCT design : adjusted hazard ratio , 1.80 ( 95 % confidence interval , 1.24 - 2.61 ) . Sixty ( 41 % ) of the 148 RCTs that were subsequently published exhibited discrepancies between the efficacy estimate reported in the meeting abstract vs the one reported in the full-length article for the primary outcome . The mean change in effect was 0.44 SDs and in 20 cases ( 14 % ) , the point estimate was statistically significant in only 1 member of the pair . The discrepancy rate was the same for late-breaking RCTs as for RCTs presented in other American College of Cardiology sessions ( P = .92 ) . CONCLUSIONS Late-breaking trials were larger , more likely to be preceded by a design paper , and less likely to report positive results than RCTs presented at other sessions , but discrepancies between the meeting abstract results and subsequent full-length publication results were common even for late-breaking trials Desipramine has the least anticholinergic and sedative effects of the first generation tricyclic antidepressant agents , but its pain-relieving potential has received little study . Other antidepressant agents -- notably amitriptyline -- are known to ameliorate postherpetic neuralgia , but those agents are often toxic . In a r and omized double-blind crossover design , we gave 26 postherpetic neuralgia patients 6 weeks of treatment with desipramine ( mean dose , 167 mg/day ) and placebo .  Nineteen patients completed both treatments ; 12 reported at least moderate relief with desipramine and two reported relief with placebo .  Pain relief with desipramine was statistically significant from weeks 3 to 6 . Psychiatric interview at entry into the study produced a diagnosis of depression for 4 patients ; pain relief was similar in depressed and nondepressed patients and was statistically significant in the nondepressed group alone . We conclude that desipramine administration relieves postherpetic neuralgia and that pain relief is not mediated by mood elevation . Blockade of norepinephrine reuptake , an action shared by desipramine , amitriptyline , and other antidepressant agents that have relieved neuropathic pain , may be involved in relief of postherpetic neuralgia Summary The effect of imipramine on  symptomatic peripheral diabetic neuropathy in 9 patients was examined in a double-blind cross-over study against placebo . The dose of imipramine was adjusted to yield optimal plasma levels of imipramine plus desipramine of 300–750 nM.Imipramine had a clear benificial effect on the symptoms of the neuropathy , whereas no changes in a range of neurophysiological measurements was detected . Despite some adverse effects , especially of an anticholinergic nature , the patients generally preferred imipramine to placebo OBJECTIVES To survey the frequency of use of indirect comparisons in systematic review s and evaluate the methods used in their analysis and interpretation . Also to identify alternative statistical approaches for the analysis of indirect comparisons , to assess the properties of different statistical methods used for performing indirect comparisons and to compare direct and indirect estimates of the same effects within review s. DATA SOURCES Electronic data bases . REVIEW METHODS The Data base of Abstract s of Review s of Effects ( DARE ) was search ed for systematic review s involving meta- analysis of r and omised controlled trials ( RCTs ) that reported both direct and indirect comparisons , or indirect comparisons alone . A systematic review of MEDLINE and other data bases was carried out to identify published methods for analysing indirect comparisons . Study design s were created using data from the International Stroke Trial . R and om sample s of patients receiving aspirin , heparin or placebo in 16 centres were used to create meta-analyses , with half of the trials comparing aspirin and placebo and half heparin and placebo . Methods for indirect comparisons were used to estimate the contrast between aspirin  and  heparin . The whole process was repeated 1000 times and the results were compared with direct comparisons and also theoretical results . Further detailed case studies comparing the results from both direct and indirect comparisons of the same effects were undertaken . RESULTS Of the review s identified through DARE , 31/327 ( 9.5 % ) included indirect comparisons . A further five review s including indirect comparisons were identified through electronic search ing . Few review s carried out a formal analysis and some based analysis on the naive addition of data from the treatment arms of interest . Few method ological papers were identified . Some valid approaches for aggregate data that could be applied using st and ard software were found : the adjusted indirect comparison , meta-regression and , for binary data only , multiple logistic regression ( fixed effect models only ) . Simulation studies showed that the naive method is liable to bias and also produces over-precise answers . Several methods provide correct answers if strong but unverifiable assumptions are fulfilled . Four times as many similarly sized trials are needed for the indirect approach to have the same power as directly r and omised comparisons . Detailed case studies comparing direct and indirect comparisons of the same effect show considerable statistical discrepancies , but the direction of such discrepancy is unpredictable . CONCLUSIONS Direct evidence from good- quality RCTs should be used wherever possible . Without this evidence , it may be necessary to look for indirect comparisons from 
    Output:
    
Placebo-controlled tricyclic trials were conducted earlier than the gabapentin trials , reported lower placebo response rates , had more method ological shortcomings , and were associated with funnel plot asymmetry .
Conclusions Though direct evidence is limited , we found no difference in likelihood of achieving pain relief between gabapentin and tricyclic antidepressants for diabetic neuropathy and post-herpetic neuralgia .