***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 and Aims Capsule endoscopy ( CE ) has the problem that lumen visualization is impaired by bubbles , bile , and debris . The benefits of bowel preparation are still controversial and the best method remains to be determined . The objective of this study was to evaluate the effect of the method of bowel preparation on the quality of visualization and on transit time . Methods The study sample consisted of 68 patients for CE . Patients were r and omly allocated to three groups . In group A ( n = 23 ) , patients fasted for 12 h before CE . In groups B ( n = 20 ) and C ( n = 25 ) , patients received 2 and 4 l of polyethylene glycol ( PEG ) , respectively .  Small bowel images were evaluated by use of a cleansing score system . Representative frames were serially selected at 5-min intervals and scored by assessment of two properties ( proportion of luminal visibility and extent of obscuration ) . Results The median scores of image quality in groups A , B , and C were 2.26 , 2.43 , and 2.55 respectively , ( P = 0.034 ) . Cecal completion rates , gastric transit time , and small bowel transit time were no different among the three groups . Detection of lesions in groups A , B , and C was 56.5 , 65.0 , and 68.0 % , respectively . Conclusions Bowel preparation with PEG result ed in better image quality than fasting alone . No significant difference was observed between 2 and 4 l. PEG 2 l rather than 4 l may be a useful method of preparation for CE BACKGROUND New bowel cleansers for colonoscopy that lead to improved efficacy , safety , and tolerability are needed . OBJECTIVE This study evaluated a nonphosphate , dual-action , low-volume , orange-flavored preparation containing sodium picosulfate and magnesium citrate ( P/MC ) . DESIGN Multicenter , assessor-blinded , r and omized , noninferiority study . SETTING University hospitals , academic medical centers , and private clinics across the United States . PATIENTS Adults preparing for colonoscopy . INTERVENTIONS P/MC versus 2 L of polyethylene glycol solution ( 2L PEG-3350 ) and two 5-mg bisacodyl tablets . MAIN OUTCOME MEASUREMENTS This phase 3 study investigated the efficacy , safety , and tolerability of split-dose administration of P/MC versus day-before dosing of 2L PEG-3350 and two 5-mg bisacodyl tablets ( SEE CLEAR I study ) . Efficacy was evaluated by using the Aronchick and Ottawa scales ; noninferiority and superiority analyses were performed . Safety was assessed by monitoring adverse events ( AEs ) . Tolerability was measured via a patient question naire . RESULTS The intent-to-treat population consisted of 601 patients who self-administered P/MC ( n = 304 ) or 2L PEG-3350 and bisacodyl tablets ( n = 297 ) . P/MC was superior to 2L PEG-3350 and bisacodyl tablets in overall colon cleansing ( 84.2 % vs 74.4 % ; 1-sided 97.5 % confidence interval [ CI ] , 3.4 ) ( Aronchick scores of excellent or good ) and in cleansing of the ascending ( 89.5 % vs 78.8 % ; 1-sided 97.5 % CI , 4.9 ) , mid ( transverse and descending ) ( 92.4 % vs 85.9 % ; 1-sided 97.5 % CI , 1.6 ) , and rectosigmoid ( 92.4 % vs 87.2 % ; 1-sided 97.5 % CI , 0.4 ) segments of the colon ( Ottawa scores of excellent , good , or fair ) . Commonly reported AEs related to the bowel preparations were nausea , vomiting , headache , and chills . Patient-reported tolerability , including ease of consumption and taste , was significantly higher for P/MC than 2L PEG-3350 and bisacodyl tablets ( P < .0001 ) . LIMITATIONS Because of differences in administration and volume of the bowel preparations , the study was design ed to be a single-assessor , blinded study . CONCLUSIONS The bowel-cleansing effects and patient acceptability of split-dose P/MC were superior to day-before dosing with 2L PEG-3350 and bisacodyl tablets Background and Study Aims To obtain an adequate view of the whole small intestine during capsule endoscopy ( CE ) a clear liquid diet and overnight fasting is recommended . However , intestinal content can hamper vision in spite of these measures . Our aim was to evaluate tolerance and degree of intestinal cleanliness during CE following three types of bowel preparation . Patients and Methods This was a prospect i ve , multicenter , r and omized , controlled study . Two-hundred ninety-one patients underwent one of the following preparations :  4 L of clear liquids ( CL ) ( group A ; 92 patients ) ; 90 mL of aqueous sodium phosphate ( group B ; 89 patients ) ; or 4 L of a polyethylene glycol electrolyte solution ( group C ; 92 patients ) . The degree of cleanliness of the small bowel was classified by blinded examiners according to four categories ( excellent , good , fair or poor ) . The degree of patient satisfaction , gastric and small bowel transit times , and diagnostic yield were measured . Results The degree of cleanliness did not differ significantly between the groups ( P = 0.496 ) . Interobserver concordance was fair ( k = 0.38 ) . No significant differences were detected between the diagnostic yields of the CE ( P = 0.601 ) . Gastric transit time was 35.7 ± 3.7 min ( group A ) , 46.1 ± 8.6 min ( group B ) and 34.6 ± 5.0 min ( group C ) ( P = 0.417 ) . Small-intestinal transit time was 276.9 ± 10.7 min ( group A ) , 249.7 ± 13.1 min ( group B ) and 245.6 ± 11.6 min ( group C ) ( P = 0.120 ) . CL was the best tolerated preparation . Compliance with the bowel preparation regimen was lowest in group C ( P = 0.008 ) . Conclusions A clear liquid diet and overnight fasting is sufficient to achieve an adequate level of cleanliness and is better tolerated by patients than other forms of preparation Objective : The aim of the study was to evaluate the tolerability , safety , and efficacy of polyethylene glycol ( PEG ) 3350 without electrolytes as a 1-day bowel preparation for colonoscopy in children . Methods : A prospect i ve study of 45 children undergoing colonoscopy prescribed PEG 3350 without electrolytes mixed with a commercial electrolyte beverage was performed . Patients < 45 kg received 136 g of PEG 3350 without electrolytes mixed in 32 ounces of Gatorade .  Patients ≥45 kg were given 255 g of PEG 3350 without electrolytes in 64 ounces of Gatorade . A basic metabolic panel was performed at the time of the clinic visit and just before colonoscopy . Patients completed a survey related to bowel preparation . Endoscopists grade d bowel preparation and noted the proximal extent of the examination . Results : A total of 44 patients ( 14 ± 3 years ) completed the study . One patient was excluded due to protocol breach . All subjects reported the preparation was easy ( 61 % ) or tolerable ( 39 % ) . Adverse events included nausea ( 34 % ) , abdominal pain ( 23 % ) , vomiting ( 16 % ) , abdominal distension ( 20 % ) , bloating ( 23 % ) , and dizziness ( 7 % ) . Although significant changes in serum glucose and CO2 were noted , no therapeutic interventions were indicated . Significant changes in sodium , potassium chloride , blood urea nitrogen , or creatinine did not occur . Colonic preparation was rated as excellent in 23 % , good in 52 % , fair in 23 % , and poor in 2 % of patients . Intubation of the ileum was successful in 100 % . Conclusions : One-day bowel preparation with high dose PEG 3350 mixed with commercial electrolyte solution is tolerable , safe , and effective in children before colonoscopy OBJECTIVE : Inadequate preparation of the bowel for colonoscopy can result in both missed pathological lesions and cancelled procedures . We looked prospect ively at the quality of colonic preparation and evaluated potential associations between specific patient characteristics and inadequate colonic preparation . METHODS : Data were gathered on consecutive patients presenting for colonoscopy who received either a polyethylene glycol lavage or oral sodium phosphate bowel preparation .  Patient demographic and medical history information was gathered before scheduled colonoscopy . The endoscopist evaluated the preparation quality during the procedure . Complete data were gathered on 649 of 714 eligible patients ( 90.8 % ) . Possible predictors of inadequate colonic preparation were analyzed using univariate statistics and multivariate logistic regression models . RESULTS : An inadequate colonic preparation was reported in 21.7 % of observed colonoscopies . Only 18 % of patients with an inadequate colonic preparation reported a failure to adequately follow preparation instructions . A later colonoscopy starting time , a reported failure to follow preparation instructions , inpatient status , a procedural indication of constipation , taking tricyclic antidepressants , male gender , and a history of cirrhosis , stroke or dementia were all independent predictors of an inadequate colon preparation ( all p < 0.05 ) . A procedural indication of previous polypectomy was a negative predictor of inadequate colonic preparation ( p < 0.05 ) . CONCLUSION : Several patient characteristics were significantly associated with colonic preparation quality independent of preparation type , compliance with preparation instructions , and procedure starting time . This information may help to identify patients at an increased risk for inadequate colonic preparation for whom alternative preparation protocol s would be appropriate BACKGROUND Several factors influence bowel preparation quality . Recent studies have indicated that the time interval between bowel preparation and the start of colonoscopy is also important in determining bowel preparation quality . OBJECTIVE To evaluate the influence of the preparation-to-colonoscopy ( PC ) interval ( the interval of time between the last polyethylene glycol dose ingestion and the start of the colonoscopy ) on bowel preparation quality in the split-dose method for colonoscopy . DESIGN Prospect i ve observational study . SETTING University medical center . PATIENTS A total of 366 consecutive out patients undergoing colonoscopy .  INTERVENTION Split-dose bowel preparation and colonoscopy . MAIN OUTCOME MEASUREMENTS The quality of bowel preparation was assessed by using the Ottawa Bowel Preparation Scale according to the PC interval , and other factors that might influence bowel preparation quality were analyzed . RESULTS Colonoscopies with a PC interval of 3 to 5 hours had the best bowel preparation quality score in the whole , right , mid , and rectosigmoid colon according to the Ottawa Bowel Preparation Scale . In multivariate analysis , the PC interval ( odds ratio [ OR ] 1.85 ; 95 % CI , 1.18 - 2.86 ) , the amount of PEG ingested ( OR 4.34 ; 95 % CI , 1.08 - 16.66 ) , and compliance with diet instructions ( OR 2.22l 95 % CI , 1.33 - 3.70 ) were significant contributors to satisfactory bowel preparation . LIMITATIONS Nonr and omized controlled , single-center trial . CONCLUSIONS The optimal time interval between the last dose of the agent and the start of colonoscopy is one of the important factors to determine satisfactory bowel preparation quality in split-dose polyethylene glycol bowel preparation OBJECTIVES : Optimal bowel preparation is vital for the efficacy and safety of colonoscopy . The inconvenience , discomfort , required consumption of large volumes of product , and potential adverse effects associated with some bowel preparations deter patients from colonoscopy and may provide inadequate cleansing . A dual-action , non-phosphate , natural orange-flavored , low-volume preparation containing sodium picosulfate and magnesium citrate ( P/MC ) is currently being review ed for bowel cleansing . METHODS : This was a phase 3 , r and omized , multicenter , assessor-blinded , prespecified non-inferiority , head-to-head study to investigate the efficacy , safety , and tolerability of day-before administration of P/MC vs. 2L polyethylene glycol solution and two 5-mg bisacodyl tablets ( 2L PEG-3350 and bisacodyl tablets ( HalfLytely and Bisacodyl Tablets Bowel Prep Kit ) ) in adult patients preparing for colonoscopy ( SEE CLEAR II Study ) . The primary objective of the study was to demonstrate the non-inferiority of P/MC to 2L PEG-3350 and bisacodyl tablets in overall colon cleansing using a modified Aronchick scale . In addition , efficacy in the ascending , mid ( transverse and descending ) , and recto-sigmoid segments of colon was evaluated using a modified Ottawa scale . Patient acceptability and tolerability of the bowel preparations were assessed via a st 
    Output:
    
FINDINGS PEG-based regimens are recommended first line for both procedures , since their use is supported by good efficacy and safety data .
Sodium-picosulphate-based regimens are recommended second line as their cleansing efficacy appears less than PEG-based regimens .
NaP is not recommended for bowel cleansing due to the potential for renal damage and other adverse events .
However , the use of NaP is acceptable in patients in whom PEG or sodium picosulphate is ineffective or not tolerated .