Tailoring Vit D information for immigrants RCT 2010
The effect of tailor-made information on vitamin D status of immigrant mothers in Norway: a cluster randomized controlled trial
Ahmed A. Madar*, Knut-Inge Klepp † and Haakon E. Meyer*‡
  *Institute of General Practice and Community Medicine, University of Oslo, Oslo, Norway,   † Department of Nutrition, Faculty of Medicine, University of Oslo, Oslo, Norway, and   ‡ Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
Correspondence to  Ahmed Madar, Institute of General Practice and Community Medicine, University of Oslo, PO Box 1130 Blindern, Oslo N-0318, Norway. E-mail: a.a.madar@medisin.uio.no
 Contributors: Ahmed Madar carried out the data collection, performed data analysis and prepared the manuscript. Professor Haakon Meyer developed the study protocol, secured initial funding and assisted in the analysis of the data. Professor Knut-Inge Klepp and Professor Haakon Meyer supervised the study. All authors commented on the draft, contributed to the interpretation of the findings and approved the final version of the manuscript. The authors declare no conflict of interest with regard to this paper.
 Trial registration number: ISRCTN78298308.
Copyright © 2010 Blackwell Publishing Ltd
KEYWORDS
randomized controlled trial • vitamin D • nutrition education • immigrant mothers • maternal nutrition • lactation
A high prevalence of vitamin D deficiency has been reported in non-Western immigrants in Norway. Our objective was to test whether written information about how to improve vitamin D status could improve the vitamin D status in immigrants mothers attending child health clinics. In this cluster randomized controlled trial in eight child health clinics in Oslo, mothers aged 18–43 years with Pakistani, Turkish, or Somali background were included when their infants were 6 weeks old. The public health nurses gave the intervention group a brochure with information on how to improve vitamin D status, written in their native language. They were compared with a control group receiving usual care, consisting of oral information only. The principal outcome measure was increase in serum 25-hydroxyvitamin D [s-25(OH) D] in mothers 7 weeks later. Forty-four mothers completed the study. Mean baseline s-25(OH) D was 29.1 (14.8) nmol l−1 in the intervention and 19.4 (9.2) in the control group. There was no significant increase in s-25(OH) D from baseline to follow-up in the intervention [6.3 (95%CI: −1.9, 14.4) nmol l−1)] or in the control group [2.9 (95% CI [confidence interval]: −1.2, 7.0) nmol l−1]. When adjusting for baseline s-25(OH) D concentration the mean difference in increase between the intervention and control group was 1.4 (95% CI: −18.7, 21.4) nmol l−1 (P = 0.87). Adjustment for ethnicity, season and mother's educational background did not alter the results. In sum, providing immigrant mothers with written information about how to improve their vitamin D status did not have an effect on the mothers' vitamin D status.