***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: OBJECTIVES A high prevalence of hip and other fractures in elderly patients with Parkinson ’s disease has been linked to reduced bone mass arising from a defect of renal synthesis of 1 , 25-dihydroxyvitamin D ( 1 , 25-[OH]2D ) . Treatment with 1α-hydroxyvitamin D3 ( 1α(OH)D3 ; an active form of vitamin D ) was evaluated for maintaining bone mass and reducing the incidence of hip and other non-vertebral fractures in patients with Parkinson ’s disease . METHODS In a double blind , r and omised trial , 86 elderly patients with Parkinson ’s disease ( mean Hoehn and Yahr stage , 3 ; mean age 70.6 years ) were r and omised to receive either 1 μg 1α(OH)D3 daily ( treatment group , n=43 ) or a placebo ( n=43 ) for 18 months . Bone mineral densities in the second metacarpals were determined by computed radiographic densitometry . Serum bone turnover indices were measured serially , and incidence of non-vertebral fractures was recorded . RESULTS Bone mineral densities decreased 1.2 % in the treatment group compared with 6.7 % in the placebo group during 18 months ( p<0.0001 ) . At baseline in both groups , the serum concentration of 1 , 25-[OH]2D was reduced . Parathyroid hormone was abnormally increased in 15 patients ( 17 % ) and correlated negatively with serum 25-hydroxyvitamin D , indicating compensatory hyperparathyroidism . Eight patients  sustained fractures ( six at the hip and two at other sites ) in the placebo group , and one hip fracture occurred among treated patients ( odds ratio 9.8 ; p=0.0028 ) . CONCLUSION By increasing serum 1 , 25-[OH]2D concentrations , treatment with 1α(OH)D3 can reduce the risk of hip and other non-vertebral fractures in osteoporotic elderly patients with Parkinson ’s disease by slowing the loss of bone mineral densities Objectives : To assess the effectiveness of a multivitamin ( MV ) tablet on nutritional status , quantitative heel ultrasound ( QUS ) , mobility , muscle strength and falls . The design comprised two groups matched on mobility levels , r and omized to receive a daily MV or placebo ( P ) tablet for 6 months . The setting was an Australian residential care facility . Subjects : A total of 92 aged care residents . Serum micronutrients , body weight , QUS , rate of falls , h and grip strength , and the timed up and go test were assessed at baseline and 6 months . Results : A total of 49 participants consumed a MV and 43 , a matched P for 6 months . There was a greater increase in the MV vs P group for serum 25(OH)D ( mean difference±st and ard error , 33.4±2.6 nmol l−1 ) , folate ( 13.4±2.8 nmol l−1 ) , and vitamin B12 ( 178.0±40.3 pmol l−1 ) ( all P<0.001 ) . Adequate 25(OH)D concentrations ( ⩾50 nmol l−1 ) were found among 77 % of participants in the MV group vs 10 % taking P ( P<0.001 ) . Adjusting for baseline levels , the increase in QUS was greater in the MV vs P group ( 3.0±2.0 dB MHz−1 vs −2.9±2.1 dB MHz−1 , respectively , P=0.041 ) . There was a trend towards a 63 % lower mean number of falls in the MV vs P group ( 0.3±0.1 falls vs 0.8±0.3 falls , P=0.078 ) . Conclusions : MV  supplementation raised serum vitamin B12 and folate concentrations and increased serum 25(OH)D , which was accompanied by an apparent positive effect on bone density . We also found a trend towards a reduction in falls and this could contribute to a reduction in fractures The National Institutes of Health 's consensus conference ( 1 ) defined osteoporosis as a skeletal disorder characterized by compromised bone strength predisposing to an increased risk for fracture . Bone strength reflects the integration of two main features : bone density and bone quality .Bone quality refers to architecture , turnover , damage accumulation ( e.g. , microfractures ) , and mineralization . Although osteoporosis can affect any bone , the hip , spine , and wrist are most likely to be affected . Osteoporosis affects an estimated 44 million Americans or 55 % of people 50 years of age or older . Another 34 million Americans are estimated to have low bone mass , meaning that they are at an increased risk for osteoporosis . Osteoporosis can be diagnosed by the occurrence of fragility fracture . In patients without fragility fracture , osteoporosis is often diagnosed by low bone density .  Dual x-ray absorptiometry ( DXA ) is the current gold st and ard test for diagnosing osteoporosis in people without an osteoporotic fracture .  Dual x-ray absorptiometry results are scored as st and ard deviations ( SDs ) from a young healthy norm ( usually female ) and reported as T-scores . For example , a T-score of 2 indicates a bone mineral density that is 2 SDs below the comparative norm . The international reference st and ard for the description of osteoporosis in postmenopausal women and in men age 50 years or older is a femoral neck bone mineral density of 2.5 SD or more below the young female adult mean ( 2 ) . Low bone density , as measured by DXA , is an imperfect predictor of fracture risk , identifying fewer than half the people who go on to have an osteoporotic fracture . Screening guidelines for women are well established ( 3 ) , and the American College of Physicians ( ACP ) recently published guidelines on screening for men ( 4 ) . This guideline presents the available evidence on various pharmacologic treatments to prevent fractures in men and women with low bone density or osteoporosis . Medications used to treat osteoporosis may affect different parts of the skeletal system differently , and efficacy for vertebral fractures does not necessarily imply efficacy for nonvertebral fractures . The target audience for this guideline is all clinicians and the target patient population is all adult men and women with low bone density or osteoporosis . These recommendations are based on the systematic evidence review by MacLean and colleagues ( 5 ) and the Agency for Healthcare Research and Quality sponsored Southern California Evidence -Based Practice Center evidence report ( 6 ) . The drugs currently approved for prevention of osteoporosis include alendronate , ib and ronate , risedronate , zoledronic acid , estrogen , and raloxifene . The drugs currently approved for treatment of osteoporosis include alendronate , ib and ronate , risedronate , calcitonin , teriparatide , zoledronic acid ( in postmenopausal women ) , and raloxifene . Testosterone , pamidronate , and etidronate are not approved by the U.S. Food and Drug Administration for the treatment or prevention of osteoporosis . Methods The literature search done by MacLean and colleagues for the systematic review ( 5 ) included studies from MEDLINE ( 1966 to December 2006 ) , the ACP Journal Club data base , the Cochrane Central Register of Controlled Trials ( no date limits ) , the Cochrane Data base of Systematic Review s ( no date limits ) , Web sites of the United Kingdom National Institute of Health and Clinical Excellence ( no date limits ) , and the United Kingdom Health Technology Assessment Program ( January 1998 to December 2006 ) . The review ers limited their search to English- language publications and human studies . They derived evidence for comparative benefits of various treatments exclusively from r and omized , controlled trials , whereas they included evidence from other types of studies for short- and long-term harms . Two physicians independently abstract ed data about study population s , interventions , follow-up , and outcome ascertainment by using a structured form . For each group within a r and omized trial , a statistician extracted the sample size and number of persons reporting fractures . Two review ers , under the supervision of the statistician , independently abstract ed information about adverse events . The statistician or the principal investigator resolved disagreements . This guideline is based on an evaluation of 76 r and omized , controlled trials , 4 of which were identified in the up date d search , and 24 meta-analyses that were included in the efficacy analyses . The analyses of adverse events included 491 articles , representing 417 r and omized trials , 25 other controlled clinical trials , 11 open-label trials , 31 large observational studies , and 9 case reports of osteonecrosis among bisphosphonate users . MacLean and colleagues ' background article ( 5 ) includes details about the methods used for the systematic evidence review . The ACP rates the evidence and recommendations by using the Grading of Recommendations , Assessment , Development , and Evaluation ( GRADE ) system with minor modifications ( Table 1 ) . In addition , the evidence review ers used predefined criteria to assess the quality of systematic review s and r and omized trials , based on internal and external validity assessment s detailed in the Quality of Reporting of Meta-Analyses ( QUOROM ) statement ( 7 ) . Table 1 . The American College of Physicians ' Guideline Grading System The objective of this guideline is to synthesize the evidence for the following questions : What are the comparative benefits in fracture reduction among and also within the following treatments for low bone density :  bisphosphonates , specifically alendronate , risedronate , etidronate , ib and ronate , pamidronate , and zoledronic acid ; calcitonin ; estrogen for women ; teriparatide ; selective estrogen receptor modulators ( SERMs ) , specifically raloxifene and tamoxifen ; testosterone for men ; vitamins and minerals , specifically vitamin D and calcium ; and the combination of calcium plus vitamin D ? How does fracture reduction result ing from treatments vary among individuals with different risks for fracture as determined by bone mineral density ( borderline , low , or severe ) , previous fractures ( prevention vs. treatment ) , age , sex , glucocorticoid use , and other factors ( such as community-dwelling vs. institutionalized or vitamin Ddeficient vs. not ) ? What are the short- and long-term harms ( adverse effects ) of these therapies , and do these vary by specific sub population s ? Comparative Benefits of Drugs versus Placebo in Fracture Reduction Evidence from 24 meta-analyses ( 830 ) and 35 additional r and omized trials published after the meta-analyses ( 3165 ) described the effect of 9 of the 14 agents ( alendronate , etidronate , risedronate , calcitonin , estrogen , teriparatide , raloxifene , calcium , and vitamin D ) on fracture incidence . For 4 agents ( ib and ronate , pamidronate , zoledronic acid , and tamoxifen ) , the review ers found no meta-analyses and instead gathered the evidence from 14 r and omized trials ( 6679 ) . No studies were found that reported fracture rates for testosterone . Three r and omized trials ( 35 , 80 , 81 ) and 1 meta- analysis ( 82 ) evaluated the combination of calcium plus vitamin D  on fractures .  Bisphosphonates Good- quality evidence showed that alendronate , etidronate , ib and ronate , and risedronate prevent vertebral fractures . In addition , evidence from good- quality studies demonstrated that both alendronate and risedronate prevent nonvertebral and hip fractures . Two large r and omized trials showed that zoledronic acid prevents vertebral and nonvertebral fractures in high-risk population s and reduces the risk for hip fracture ( 67 , 74 ) . Ib and ronate has not been shown to reduce nonvertebral fractures ( 68 ) . Of the 6 fairly small trials that looked at vertebral fractures , 1 demonstrated a statistically significant reduction in fractures with pamidronate relative to placebo ( 0.14 [ 95 % CI , 0.03 to 0.72 ] ) ( 73 ) . However , after these data were pooled , the pooled risk estimate for fractures for pamidronate relative to placebo was not significant ( 0.52 [ CI , 0.21 to 1.24 ] ) ( 6 ) . Calcitonin Fair- quality evidence shows that calcitonin reduces vertebral fractures ( 83 , 84 ) . Good- quality evidence indicates that calcitonin does not reduce nonvertebral fractures ( 13 , 16 ) . Estrogen Good- quality evidence shows that estrogen reduces the incidence of vertebral ( 29 , 85 ) , nonvertebral ( 86 ) , and hip fractures ( 85 ) . Teriparatide Good- quality evidence shows that teriparatide prevents vertebral fractures . The evidence related to teriparatide preventing nonvertebral fractures is mixed ; 1 large r and omized trial showed a reduction in nonvertebral fractures ( 34 ) but 2 small trials did not ( 87 , 88 ) . SERMs Good- quality evidence shows that raloxifene prevents vertebral fractures , but 
    Output:
    
We found evidence that this group of affected trial reports distorted the evidence base .
Correction of these distortions is slow , uncoordinated and inconsistent .