No customers was basically involved in means the research question and/or consequences methods, neither was indeed it active in the structure and you may utilization of brand new investigation.
Provided knowledge was in fact randomised regulated trials inside people aged >fifty during the baseline with BMD measured because of the twin opportunity x ray absorptiometry (DXA) or precursor technology such as photon absorptiometry. I included training you to reported bone mineral stuff (BMC) due to the fact BMD is obtained from the splitting BMC from the bone urban area and you can in addition to a couple are extremely synchronised. Training where really users from the baseline had a major general pathology aside from osteoporosis, including kidney failure or cancer malignancy, was in fact omitted. I integrated training from calcium used in combination with almost every other procedures so long as others medication got so you can both of your arms (such as for example calcium supplements and nutritional K in the place of placebo and supplement K), and you will studies off co-given calcium supplements and you can vitamin D supplements (CaD). Randomised regulated samples out-of hydroxyapatite while the a diet source of calcium supplements had been integrated because it is created from bone possesses almost every other nutritional elements, hormone, protein, and you may proteins together with calcium supplements. You to definitely blogger (WL or MB) processed titles and abstracts, as well as 2 experts (WL, MB, otherwise VT) on their own processed the full text message away from possibly associated training. The newest circulate away from blogs is actually revealed when you look at the figure A beneficial during the appendix dos.
Studies extraction and synthesis
I removed information regarding each study on participants’ attributes, research framework, capital origin and you can problems of interest, and you can BMD at the lumbar back, femoral shoulder, overall cool, forearm, and you will full system. BMD would be counted on multiple sites on forearm, as the 33% (1/3) distance was most often utilized. For every data, we made use of the advertised studies with the forearm, regardless of website. If more than one site try advertised, i utilized the data towards the web site closest towards 33% distance. One journalist (VT) removed research, that happen to be checked from the another copywriter (MB). Threat of bias try assessed because the needed in the Cochrane Handbook.11 One inaccuracies was in fact resolved through conversation.
The primary endpoints were the percentage changes in BMD from baseline at the five BMD sites. We categorised the studies into three groups by duration: one year was duration <18 months; two years was duration ?18 months and ?2.5 years; and others were studies lasting more than two and a half years. For studies that presented absolute data rather than percentage change from baseline, we calculated the mean percentage change from the raw data and the standard deviation of the percentage change using the approach described in the Cochrane Handbook.11 When data were presented only in figures, we used digital callipers to extract data. In four studies that reported mean data but not measures of spread,12 13 14 15 we imputed the standard deviation for the percentage change in BMD for each site from the average site and duration specific standard deviations of all other studies included in our review. We prespecified subgroup analyses based on the following variables: dietary calcium intake v calcium supplements; risk of bias; calcium monotherapy v CaD; baseline age (<65); sex; community v institutionalised participants; baseline dietary calcium intake <800 mg/day; baseline 25-hydroxyvitamin D <50 nmol/L; calcium dose (?500 v >500 mg/day and <1000 v ?1000 mg/day); and vitamin D dose <800 IU/day.
We pooled the data using random effects meta-analyses and assessed for heterogeneity between studies using the I 2 statistic (I 2 >50% was considered significant heterogeneity). Funnel plots and Egger’s regression model were used to assess for the likelihood of systematic bias. We included randomised controlled trials of calcium with or without vitamin D in the primary analyses. Randomised controlled trials in which supplemental vitamin D was provided to both treatment groups, so that the groups differed only in treatment by calcium, were included in calcium monotherapy subgroup analyses, while those comparing co-administered CaD with placebo or controls were included in the CaD subgroup analyses. We included all available data from trials with factorial designs or multiple arms. Thus, for factorial randomised controlled trials we included all study arms involving a comparison of calcium versus no calcium in the primary analyses and the calcium monotherapy subgroup analysis, but only arms comparing CaD with controls in the CaD subgroup analysis. For multi-arm randomised controlled trials, we pooled data from the separate treatment arms for the primary analyses, but each treatment arm was used only once. We undertook analyses of prespecified subgroups using a random effects model when there were 10 or more studies in the analysis and three or more studies in each subgroup milfaholic Гјcretsiz uygulama and performed a test for interaction between subgroups. All tests were two tailed, and P<0.05 was considered significant. All analyses were performed with Comprehensive Meta-Analysis (version 2, Biostat, Englewood, NJ).