***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 test the feasibility of creating a valid and reliable checklist with the following features : appropriate for assessing both r and omised and non-r and omised studies ; provision of both an overall score for study quality and a profile of scores not only for the quality of reporting , internal validity ( bias and confounding ) and power , but also for external validity . DESIGN : A pilot version was first developed , based on epidemiological principles , review s , and existing checklists for r and omised studies . Face and content validity were assessed by three experienced review ers and reliability was determined using two raters assessing 10 r and omised and 10 non-r and omised studies . Using different raters , the checklist was revised and tested for internal consistency ( Kuder-Richardson 20 ) , test-retest and inter-rater reliability ( Spearman correlation coefficient and sign rank test ; kappa statistics ) , criterion validity , and respondent burden . MAIN RESULTS : The performance of the checklist improved considerably after revision of a pilot version . The Quality Index had high internal consistency ( KR-20 : 0.89 ) as did the subscales apart from external validity ( KR-20 : 0.54 ) . Test-retest ( r 0.88 ) and inter-rater ( r 0.75 ) reliability of the Quality Index were good . Reliability of the subscales varied from good ( bias ) to poor ( external validity ) . The Quality Index correlated highly with an existing , established instrument for assessing r and omised studies ( r 0.90 ) . There was little difference between its performance with non-r and omised and with r and omised studies . Raters took about 20 minutes to assess each paper ( range 10 to 45 minutes ) . CONCLUSIONS : This study has shown that it is feasible to develop a checklist that can be used to assess the method ological quality not only of r and omised controlled trials but also non-r and omised studies . It has also shown that it is possible to produce a checklist that provides a profile of the paper , alerting review ers to its particular method ological strengths and weaknesses . Further work is required to improve the checklist and the training of raters in the assessment of external validity INTRODUCTION The objective of this study was to evaluate the effectiveness of the light-force chincup appliance in correcting the skeletal and dentoalveolar components of Class III malocclusion compared with an untreated Class III control group . METHODS The treatment sample consisted of 26 patients ( 11 boys , 15 girls ) treated with the light-force chincup ( 125 - 250 g ) . The mean age at the start of treatment in the chincup group was 8.5 years , with posttreatment cephalograms taken on average 2.6 years later . The control group consisted of 20 subjects . The mean age at the start of observation for the control group ( 6 boys , 14 girls ) was 7.3 years , and the mean time of observation was 2.4 years . Lateral cephalograms were analyzed with a specific tracing regimen at the 2 time points for both groups . Treatment outcome were determined . The treatment group subsequently was subdivided into those treated simultaneously with a quad-helix appliance and those with the chincup only . Mann-Whitney U tests for independent sample s were performed to evaluate the differences between the treated and untreated groups at both time points , the changes between the 2 time points , and the differences between the groups treated with the quad-helix and chincup , and the chincup only . RESULTS The chincup sample showed no significant skeletal changes in the m and ible in either the vertical or horizontal direction , except for a slight decrease in SNB angle and an increase in ANB angle . There were significant dentoalveolar changes , particularly uprighting of the m and ibular incisors . Significant positive Class III treatment outcomes were recorded in the quad-helix group , including a decrease in m and ibular length of 1.9 mm compared with the chincup group . CONCLUSIONS Fewer than 50 % of the subjects treated with the chincup had favorable clinical outcomes . Correction of the initial Class III malocclusion occurred through significant dentoalveolar changes . The light-force chincup did not produce orthopedic changes in the m and ible . Maxillary expansion with a quad-helix might aid in the correction of the Class III malocclusion in conjunction with the chincup This study was conducted on lateral cephalograms and magnetic resonance images ( MRIs ) obtained from 20 subjects with Class III malocclusion . Only clinical ly temporom and ibular joint ( TMJ ) symptom-free subjects were included in this study . In the treatment group , a chin cup with 600 g of force was applied in 13 patients ( 10 girls and three boys ) with a mean age of nine years . The chin cup was applied in a direction from the chin toward the TMJ . The control group consisted of seven patients ( six girls and one boy ) with a mean age of eight year nine months .  Orthodontic treatment was not applied in the control group . Records were taken at the beginning and end of chin cup therapy from all the subjects . Measurements were made on lateral cephalograms and unilateral-left sagittal-oblique TMJ MRIs . Variables obtained at the beginning and end of the study were compared by Student 's t-tests and paired t-tests . Relationships between craniofacial and TMJ variables were analyzed by correlation analysis . The m and ibular corpus length was increased and condylar head angle was decreased by chin cup therapy . A positive correlation existed between activation of sagittal maxillary and m and ibular growth and bending of the condylar head . This study showed that the condylar growth pattern was altered by chin cup . It may be implied that the source of improvement is adaptation of the craniofacial structures to the changes of the condylar growth pattern produced by the chin cup BACKGROUND / PURPOSE Little information related to the treatment effects of the occipitomental anchorage ( OMA ) appliance of maxillary ( Mx ) protraction combined with chincup traction is available . The aim of this study was to investigate the treatment effects of the OMA orthopedic appliance on patients with Class III malocclusion . METHODS Pretreatment and post-treatment cephalometric records of 20 consecutively treated patients with Class III malocclusions were evaluated and compared with a matched sample of untreated Class III control subjects . RESULTS The OMA appliance is effective for correcting skeletal Class III malocclusion in growing children . The treatment effects of this orthopedic appliance were considered to be from both skeletal and dentoalveolar changes . The skeletal effects were mainly obtained by stimulating forward growth of the Mx complex with negligible rotation of the Mx plane and restraining forward advancement of the m and ible ( Mn ) with backward and downward rotation of the Mn plane . The observed dentoalveolar effects were mostly due to the labial tipping movement of the Mx incisors . CONCLUSION Our results suggest that the OMA orthopedic appliance can correct the mesial jaw relationship and negative incisal over jet . This appliance is effective for correcting skeletal Class III malocclusion with both midface deficiency and Mn prognathism in growing children 
    Output:
    
In comparison to untreated individuals , the SNB and gonial angles decreased significantly following chin cup use , whereas ANB , Wits appraisal , SN-ML , N-Me and overjet increased .
For the rest of the variables , no statistically significant differences were detected .