***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: BACKGROUND While electroconvulsive therapy ( ECT ) in major depression is effective , cognitive effects limit its use . Reducing the width of the electrical pulse and using the right unilateral electrode placement may decrease adverse cognitive effects , while preserving efficacy . METHODS In a double-masked study , we r and omly assigned 90 depressed patients to right unilateral ECT at 6 times seizure threshold or bilateral ECT at 2.5 times seizure threshold  , using either a traditional brief pulse ( 1.5 ms ) or an ultrabrief pulse ( 0.3 ms ) . Depressive symptoms and cognition were assessed before , during , and immediately , two , and six months after therapy . Patients who responded were followed for a one-year period . RESULTS The final remission rate for ultrabrief bilateral ECT was 35 percent , compared with 73 percent for ultrabrief unilateral ECT , 65 percent for st and ard pulse width bilateral ECT , and 59 percent for st and ard pulse width unilateral ECT ( all P's<0.05 after covariate adjustment ) . The ultrabrief right unilateral group had less severe cognitive side effects than the other 3 groups in virtually all primary outcome measures assessed in the acute postictal period , and during and immediately following therapy . Both the ultrabrief stimulus and right unilateral electrode placement produced less short- and long-term retro grade amnesia . Patients rated their memory deficits as less severe following ultrabrief right unilateral ECT compared to each of the other three conditions ( P<0.001 ) . CONCLUSIONS The use of an ultrabrief stimulus markedly reduces adverse cognitive effects , and when coupled with markedly suprathreshold right unilateral ECT , also preserves efficacy . ( Clinical Trials.gov number , NCT00487500 . ) OBJECTIVE Substantial progress has been made in identifying how the treatment parameters used in ECT impact on cognitive side effects . However , there is limited information regarding individual differences in vulnerability to these side effects . The authors examined patients ' pretreatment global cognitive status and postictal orientation recovery time as potential predictors of the magnitude of retro grade amnesia for autobiographical memories after ECT . METHOD Seventy-one in patients with major depressive disorder were r and omly assigned to four ECT conditions that varied in electrode placement ( right unilateral versus bilateral ) and stimulus dosage ( low versus high intensity ) . Orientation recovery time was assessed at virtually every session during the course of ECT .  Global cognitive status was assessed with the modified Mini-Mental State examination before treatment , during the week after termination of treatment , and 2 months after treatment ended . Retro grade amnesia was assessed at these same time points with the Autobiographical Memory Interview . RESULTS Pre-ECT global cognitive status and the duration of postictal disorientation were strong predictors of the magnitude of retro grade amnesia in the week after the course of ECT and at 2-month follow-up . In general , these relationships were maintained regardless of technical parameters in the administration of the ECT . CONCLUSIONS Patients who manifest global cognitive impairment before treatment and patients who experience prolonged disorientation in the acute postictal period may be the most vulnerable to persistent retro grade amnesia for autobiographical information Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more This double-blind , r and om-assignment study contrasted the relative efficacy of bilateral and unilateral right ECT with a low-dose titration procedure . In 52 patients with primary major depressive disorder , bilateral ECT was markedly superior in short-term symptom reduction to unilateral right ECT . The two conditions did not differ in the duration of generalized seizures or in the number of treatments administered to achieve clinical response . The findings challenge the cl aim that the elicitation of generalized seizure is , in and of itself , sufficient for the antidepressant properties of ECT . Rather , a dose in excess of seizure threshold may contribute to the efficacy of ECT , particularly with a unilateral right electrode placement BACKGROUND The antidepressant and cognitive side effects of  right unilateral ( RUL ) electroconvulsive therapy ( ECT ) are reported to depend on the magnitude of the electrical stimulus relative to the seizure threshold . The stimulus doses explored in previous clinical trials of RUL ECT have generally been limited to 1 to 2.5 times the convulsive threshold and the antidepressant efficacy has been low compared with bilateral ( BL ) ECT . The present study compares the antidepressant and cognitive side effects of 2 RUL dosing strategies : titrated moderately suprathreshold and fixed high dose . METHODS Seventy-two adult patients with major depression were r and omized to either titrated RUL ECT at 2.25 times initial seizure threshold ( mean dose , 136 millicoulombes [ mC ] ) , or RUL ECT at a fixed dose of 403 mC. Primary outcome measures were antidepressant response and cognitive status 1 or 2 days after the course of ECT . RESULTS The 2 treatment groups were comparable in demographic and clinical characteristics prior to ECT . Both groups received a mean of 5.7 sessions of RUL ECT . Patients receiving fixed-dose ECT were more likely to have an antidepressant response at the end of the protocol ( n = 49 [ 67 % ] ) compared with those receiving titrated dosing ( n = 28 [ 39 % ] ) . Furthermore , the likelihood of both antidepressant response and cognitive deficits increased as stimulus dose increased relative to initial seizure threshold , up through 8 to 12 times the threshold . CONCLUSIONS The antidepressant efficacy and cognitive side effects of RUL ECT are dependent on the magnitude of the stimulus dose relative to the seizure threshold , and a dose-response relationship extends through at least 12 times the seizure threshold Right unilateral ( RUL ) ECT is reported to have fewer memory side effects than bilateral ( BL ) ECT . We compared RUL ECT at eight times the seizure threshold ( ST ) against BL ECT at 1.5 times the ST . Adults with major depression were r and omly assigned to RUL ECT at eight times ST or BL ECT at 1.5 times the ST . Blinded ratings of mood and memory were made before ECT , 1 to 3 days after the final ECT , and at 2 and 4 weeks after ECT . Forty patients received RUL and 37 received BL ECT .  The antidepressant response rate was not significantly different for the RUL and BL groups ( 60 % vs. 73 % ) . Sustained antidepressant response , accompanied by recovery from antero grade memory side effects , was seen through the first month with both treatments . Measures of mood and memory were not significantly different for the two groups at any time point . The modest sample sizes of this study do not rule out a type II error in the detection of small but meaningful differences between assigned treatments . Also , the period of post-ECT observation consisted of 1 month of naturalistic treatment . Both RUL ECT at eight times the ST and BL ECT at 1.5 times the ST produce similar mood and memory effects . Both forms of ECT produced acceptable antidepressant response rates and only transient antero grade amnesia . No clear advantage emerged for either form of ECT , and both are justifiable as first-line techniques of ECT CONTEXT Medication resistance is the leading indication for use of electroconvulsive therapy ( ECT ) in major depression . The practice of stopping antidepressant medications prior to ECT derived from studies in the 1960s and 1970s in nonresistant sample s. There is also continuing controversy regarding the relative efficacy and adverse effects of right unilateral and bilateral ECT . OBJECTIVE To test the hypotheses that , compared with placebo , concomitant treatment with nortriptline or venlafaxine during the ECT course enhances short-term efficacy without a meaningful effect on adverse effects and reduces the rate of post-ECT relapse , and to test the hypotheses that high-dose , right-sided , unilateral ECT is equivalent in efficacy to moderate-dosage bilateral ECT and retains advantages with respect to cognitive adverse effects . DESIGN Prospect i ve , r and omized , triple-masked , placebo-controlled study conducted from 2001 through 2005 . SETTING Three university-based hospitals . PATIENTS Of approximately 750 consecutive patients referred for ECT , 319 with a major depressive episode consented , were r and omized to pharmacological or ECT treatment conditions , and received at least 1 ECT treatment . MAIN OUTCOME MEASURES Scores on the Hamilton Rating Scale for Depression , remission rate following completion of ECT , and selective measures of cognitive adverse effects . RESULTS Treatment with nortriptyline enhanced the efficacy and reduced the cognitive adverse effects of ECT relative to placebo . Venlafaxine result ed in a weaker degree of improvement and tended to worsen cognitive adverse effects . High-dosage right unilateral ECT did not differ or was superior to bilateral ECT in efficacy and result ed in less severe amnesia . CONCLUSIONS The efficacy of ECT is substantially increased by the addition of an antidepressant medication , but such medications may differ in whether they reduce or increase cognitive adverse effects . High-dose , right-sided , unilateral ECT is at least equivalent to moderate-dosage bilateral ECT in efficacy , but retains advantages with respect to cognitive adverse effects OBJECTIVE ECT is the most effective treatment for severe depression . Previous efficacy studies , using thrice-weekly brief-pulse ECT , reported that high-dose ( 6 × seizure threshold ) right unilateral ECT is similar to bitemporal ECT but may have fewer cognitive side effects . The authors aim ed to assess the effectiveness and cognitive side effects of twice-weekly moderate-dose ( 1.5 × seizure threshold ) bitemporal ECT with high-dose unilateral ECT in real-world practice . METHOD This was a pragmatic , patient- and rater-blinded , noninferiority trial of patients with major depression ( N=138 ; 63 % female ; age=56.7 years [ SD=14.8 ] ) in a national ECT service with a 6-month follow-up . Participants were independently r and omly assigned to bitemporal or high-dose unilateral ECT . The primary outcome was change in the 24-item Hamilton Depression Rating Scale ( HAM-D ) score after the ECT course ; the prespecified noninferiority margin was 4.0 points . Secondary outcomes included response and remission rates , relapse status after 6 months , and cognition . RESULTS Of the eligible patients , 69 were assigned to bitemporal ECT and 69 to unilateral ECT . High-dose unilateral ECT was noninferior to bitemporal ECT regarding the 24-item HAM-D scores after the ECT course ( mean difference=1.08 points in favor of unilateral ECT [ 95 % CI=-1.67 to 3.84 ] ) . There were no significant differences for response and remission or 6-month relapse status . Recovery of orientation was quicker following unilateral ECT ( median=19.1 minutes versus 26.4 minutes ) . Bitemporal ECT was associated with a lower percent recall of autobiographical information ( odds ratio=0.66 ) that persisted for 6 months . CONCLUSIONS Twice-weekly high-dose unilateral ECT is not inferior to bitemporal ECT for depression and may be preferable because of its better cognitive side-effect profile BACKGROUND Electroconvulsive therapy ( ECT ) is the treatment of choice in some older patients with severe depression . When compared with younger depressed patients , older patients have been shown to be as likely to respond to ECT but more likely to develop cognitive impairment . This study addresses whether adults aged 50 years and over who have already failed to respond to at least 5 moderate-charge right unilateral ( RUL ) ECT treatments ( 150 % above seizure threshold ) are more likely to benefit from a switch to high-charge RUL ECT ( 450 % above threshold ) or to bilateral ( BL ) ECT . METHOD Twenty-four patients who were treated with 5 to 8 moderate-charge RUL ECT treatments and who failed to improve sufficiently were r and omly assigned to receive either BL ECT ( N = 11 ) or high-charge RUL ECT ( N = 13 ) . Depressive ( 24-item Hamilton Rating Scale for Depression ) and cognitive scores ( Mini-Mental State Examination [ MMSE ] ) were compared under double-blind conditions at 3 phases of treatment . RESULTS Patients in the BL ECT group exhibited significantly greater cognitive impairment ( mean MMSE score decrease of 1.13 ) than those receiving high-charge RUL ECT ( mean MMSE increase of 1.71 ) . There were no statistically significant differences in clinical response to BL or high-charge RUL ECT ( 63.6 % and 61.5 % , respectively ) or in depressive symptom remission ( 18.1 % and 46.2 % ) . CONCLUSION These results suggest that older patients who fail to respond to moderate-charge RUL ECT may benefit from a switch to high-charge RUL ECT rather than BL ECT . Larger future studies will be needed to compare clinical response in patients switched from moderate-dose RUL ECT to higher-dose 
    Output:
    
High-dose unilateral ECT does not differ from moderate-dose bitemporal ECT in antidepressant efficacy but has some cognitive advantages