INTERPRETATION Results indicate that vitamin D has a protective effect against RTI , and dosing once-daily seems most effective .
BACKGROUND Low levels of 25-OH vitamin D are associated with  respiratory tract infection ( RTI ) .
However , results from r and omized controlled trials are inconclusive .
Therefore , we performed a systematic review and meta- analysis to assess the preventive effect of vitamin D supplementation on RTI .
Effect of high-dosage cholecalciferol and extended physiotherapy on complications after hip fracture: a randomized controlled trial.
BACKGROUND Care of elderly patients after hip fracture is not well established . METHODS We enrolled 173 patients with acute hip fracture who were 65 years or older ( 79.2 % women ; mean age , 84 years ; 77.4 % living at home ) . Using a factorial design , we r and omly allocated patients to extended physiotherapy ( PT ) ( supervised 60 min/d during acute care plus an unsupervised home program ) vs st and ard PT ( supervised 30 min/d during acute care plus no home program ; single-blinded ) , and to cholecalciferol therapy , 2000 vs 800 IU/d ( double-blinded ) . Primary outcome was rate of falls ; secondary outcome was rate of hospital readmissions during the 12-month follow-up . All analyses included 173 individuals and used multivariate Poisson regression analyses . RESULTS At baseline , 50.9 % of participants had 25-hydroxyvitamin D levels of less than 12 ng/mL and 97.7 % of less than 30 ng/mL. We documented 212 falls and 74 hospital readmissions . Because this was a factorial design trial , all analyses tested the main effect of each treatment while controlling for the other in 173 participants . Extended vs st and ard PT reduced the rate of falls by 25 % ( 95 % confidence interval [ CI ] , -44 % to -1 % ) . Cholecalciferol treatment , 2000 vs 800 IU/d , did not reduce falls ( 28 % ; 95 % CI , -4 % to 68 % ) , but reduced the rate of hospital readmissions by 39 % ( 95 % CI , -62 % to -1 % ) . CONCLUSIONS Extended PT was successful in reducing falls but not hospital readmissions , whereas cholecalciferol treatment , 2000 IU/d , was successful in reducing hospital readmission but not falls . Thus , the 2 strategies may be useful together because they address 2 different and important complications after hip fracture
INTERPRETATION Results indicate that vitamin D has a protective effect against RTI , and dosing once-daily seems most effective .
BACKGROUND Low levels of 25-OH vitamin D are associated with  respiratory tract infection ( RTI ) .
However , results from r and omized controlled trials are inconclusive .
Therefore , we performed a systematic review and meta- analysis to assess the preventive effect of vitamin D supplementation on RTI .