Overall , intervention groups obtained higher 25(OH)D concentration than controls and there was obvious dose – response effect between intake dose and 25(OH)D concentration .
Baseline 25(OH)D concentration and age were significant indicators for 25(OH)D concentration .
Conclusions Regional- and age-specific recommended dosages of VitD supplements for population to achieve optimal 25(OH)D concentrations have been suggested
Background / Objectives Optimal doses of vitamin D ( VitD ) supplement in different population s are unclear .
We aim to evaluate the relationship between VitD supplementation and post-intervention serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , to provide a recommended dosage of VitD for achieving an optimal 25(OH)D concentration for different population s .
The relationship between maternal self-efficacy, compliance and outcome in a trial of vitamin D supplementation in pregnancy
Summary In a r and omised controlled trial of vitamin D during pregnancy , we demonstrated that women with lower self-efficacy were more likely to experience practical problems with taking the trial medication and that this was associated with lower compliance and achieved 25(OH)-vitamin D concentrations . Introduction The relationship between self-efficacy ( the belief that one can carry out a behaviour ) , compliance with study protocol and outcome was explored within a r and omised , double-blind , placebo-controlled trial of vitamin D supplementation in pregnancy . Methods In the Maternal Vitamin D Osteoporosis Study ( MAVIDOS ) trial , women with circulating plasma 25(OH)-vitamin D of 25–100 nmol/l in early pregnancy were r and omised to either 1000 IU cholecalciferol/day or matched placebo from 14 weeks until delivery . Circulating 25(OH)-vitamin D concentrations were assessed at 14 and 34 weeks ’ gestation . A sequential sub- sample completed Schwarzer ’s General Self-Efficacy Scale at 14 and 34 weeks and the Problematic Experiences of Therapy Scale at 34 weeks . Women were interviewed about their experiences of the trial and interview transcripts analysed thematically . Results In 203 women , those with higher self-efficacy were less likely to experience practical problems taking the study medication ( odds ratio ( OR ) 0.81 ( 95 % confidence interval ( CI ) 0.69–0.95 ) , p = 0.01 ) . Over half reported practical problems associated with poorer compliance with the protocol requiring women to take the medication daily . Compliance in women who experienced practical problems was 94 % compared with 98 % for those with no problems ( p < 0.001 ) . Poorer compliance was also associated with lower concentrations of 25(OH)-D in late pregnancy in the treatment group ( β = 0.54 nmol/l ( 95 % CI 0.18–0.89 ) , p = 0.003 ) . Thematic analysis suggested common difficulties were remembering to take the medication every day and swallowing the large capsules . Conclusions These findings suggest that differences in self-efficacy influence trial outcomes . Such information may help clinicians anticipate responses to routine vitamin D supplementation in pregnancy and identify those who may need more support to comply . Trial registration IS RCT N82927713 , registered 11/04/2008
Overall , intervention groups obtained higher 25(OH)D concentration than controls and there was obvious dose – response effect between intake dose and 25(OH)D concentration .
Baseline 25(OH)D concentration and age were significant indicators for 25(OH)D concentration .
Conclusions Regional- and age-specific recommended dosages of VitD supplements for population to achieve optimal 25(OH)D concentrations have been suggested
Background / Objectives Optimal doses of vitamin D ( VitD ) supplement in different population s are unclear .
We aim to evaluate the relationship between VitD supplementation and post-intervention serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , to provide a recommended dosage of VitD for achieving an optimal 25(OH)D concentration for different population s .