Evidence from trials with vitamin D and /or calcium supplementation suggests that combined vitamin D and calcium supplementation may have a role in the prevention of type 2 DM only in population s at high risk ( i.e. glucose intolerance ) .
Vitamin D and calcium insufficiency may negatively influence glycemia , whereas combined supplementation with both nutrients may be beneficial in optimizing glucose metabolism
CONTEXT Altered vitamin D and calcium homeostasis may play a role in the development of type 2 diabetes mellitus ( type 2 DM ) .
Transition from meeting abstract to full-length journal article for randomized controlled trials.
CONTEXT Not all research presented at scientific meetings is subsequently published and , even when it is , there may be inconsistencies between these results and what is ultimately printed . Although late-breaking trials sessions are now integrated into several major scientific meetings and the results are often promptly and prominently communicated , no studies have examined the publication fate and degree of consistency between meeting abstract s or presentations and subsequent full-length article publications for r and omized controlled trials ( RCTs ) presented at these sessions . OBJECTIVE To compare RCT abstract s presented in the late-breaking trials session vs other sessions at a major scientific meeting and subsequent full-length publications . DESIGN RCTs were identified by h and search ing abstract proceedings booklets and related Web sites for the American College of Cardiology scientific meetings ( 1999 - 2002 ) . Subsequent full-length articles were identified via electronic data bases . MAIN OUTCOME MEASURES Publication fate and degree of consistency between meeting abstract results and subsequent full-length publication results . RESULTS The 86 late-breaking RCTs were significantly larger ( median , 2737 patients vs 896 ; P<.001 ) , were more likely to be preceded by a published design paper ( 27 [ 31 % ] vs 13 [ 13 % ] ; P = .002 ) , had higher quality scores when eventually published ( mean Jadad score 2.69 vs 2.19 ; P = .01 ) , and were less likely to report favorable results for the intervention than the 100 r and omly chosen comparison RCTs presented in other sessions ( 50 [ 58 % ] vs 75 [ 75 % ] ; P = .01 ; odds ratio 0.46 ; 95 % confidence interval , 0.24 - 0.90 ) . RCTs presented at the late-breaking trials sessions were significantly more likely to be published ( 79 [ 92 % ] vs 69 [ 69 % ] ; P<.001 ) and appeared earlier after presentation ( median 11.5 months vs 22.0 months ; P<.001 ) than RCTs presented in other sessions , an association that persisted even after adjusting for sample size , conclusion of study , and RCT design : adjusted hazard ratio , 1.80 ( 95 % confidence interval , 1.24 - 2.61 ) . Sixty ( 41 % ) of the 148 RCTs that were subsequently published exhibited discrepancies between the efficacy estimate reported in the meeting abstract vs the one reported in the full-length article for the primary outcome . The mean change in effect was 0.44 SDs and in 20 cases ( 14 % ) , the point estimate was statistically significant in only 1 member of the pair . The discrepancy rate was the same for late-breaking RCTs as for RCTs presented in other American College of Cardiology sessions ( P = .92 ) . CONCLUSIONS Late-breaking trials were larger , more likely to be preceded by a design paper , and less likely to report positive results than RCTs presented at other sessions , but discrepancies between the meeting abstract results and subsequent full-length publication results were common even for late-breaking trials
Evidence from trials with vitamin D and /or calcium supplementation suggests that combined vitamin D and calcium supplementation may have a role in the prevention of type 2 DM only in population s at high risk ( i.e. glucose intolerance ) .
Vitamin D and calcium insufficiency may negatively influence glycemia , whereas combined supplementation with both nutrients may be beneficial in optimizing glucose metabolism
CONTEXT Altered vitamin D and calcium homeostasis may play a role in the development of type 2 diabetes mellitus ( type 2 DM ) .