Jessy El Hayek et al. that limits endogenous vitamin D synthesis (15) may also play a role in predisposing Inuit children to poor bone health. The quantitative ultrasound technique is being used among the paediatric population and its parameters, particularly broadband ultrasound attenuation (BUA) and speed of sound (SoS), correlate well with BMD and with bone quality measures (16). Therefore, the primary objective of this study was to investigate whether anthropometric, dietary, biochem- ical and lifestyle risk factors are associated with bone health, as reflected by BUA and SoS among Inuit preschoolers (3 5 years) living in Arctic communities (568 32? 728 40?N). We hypothesize, based on the literature, that vitamin D and calcium intake, body mass index (BMI), and plasma 25-hydroxy vitamin D (25(OH)D) would be important predictors of SoS and BUA. Materials and methods Subjects The sample consisted of Inuit preschool children re- cruited in the late summer and early fall of 2007 (August November) and 2008 (August September) in 16 of the 25 communities of Nunavut, representing all 3 regions of the territory (Kivalliq, Baffin, and Kitikmeot). Commu- nities were selected based upon logistical and cost consideration and upon achieving representation of latitude, region, and community size. Inclusion criteria for participation consisted of self-identified Inuk by parents or a caregiver and 3 5 years of age. Children were recruited from both the community health centre lists of age-appropriate children and from randomly selected households with 3 5 year-olds that had partici- pated in the International Polar Year Inuit Adult Health Survey. A randomized list of children was created from the health centre list using a random number table and parents/caregivers were contacted in the order that they appeared on the list. Caregivers were contacted either by phone, when available, or in person. Of the 537 success- fully contacted households, 75 refused upon initial contact and 74 cancelled or failed to attend the study appointment; thus, the overall participation rate was 72.3% and 388 children were recruited. A more detailed description of the survey methodology is available elsewhere (17). Ethics The study was approved by the McGill Faculty of Medicine Institutional Review Board and by the Nunavut Research Institute. A parent or primary caregiver pro- vided signed informed consent. A person was considered a child’s primary caregiver if he/she was the person primarily responsible for the child at the time of the study. Consent forms and an information DVD were available in English and Inuit languages. Research team and interviews The research team consisted of bilingual interviewers who conducted face-to-face interviews. Information about household composition, living conditions, diet, supple- ment use, and health status were collected through interviews with the child’s caregiver. Information about sun exposure was collected. Caregivers were asked an open ending question ‘‘on average, about how many hours per day, does your child play outside?’’ A qualitative food frequency questionnaire (FFQ) (without assessment of portion sizes) was completed by the child’s caregiver. The FFQ reflected the previous month and contained 30 commonly consumed TF items, some of which are considered good sources of vitamin D, (whitefish, arctic char, seal meat, seal liver, caribou, caribou liver, polar bear meat and walrus meat). It also contained the following MF sources of vitamin D: milk, margarine, and eggs. Furthermore, 24-hour dietary re- calls (24-h recalls) were conducted with the caregiver using a multiple pass technique. Portion sizes were estimated using a 3-dimensional food model kit (Sante´ Quebec) to better standardize 24-h recalls. Twenty percent of the caregivers were asked to return for a repeat 24-h recall, which was conducted on a non- consecutive day to allow assessment of nutrient adequacy. Interviewers recorded if there were times when the caregiver did not know what the child ate. Daycares were called regarding daycare snacks and meals to complete dietary recall. This approach has been shown to be an accurate method of assessing intake in this age group (18). Vitamin D and calcium intakes were adjusted for the second 24-h recall and an estimation of the adjusted intake for sequence and day of week was calculated using the Iowa State Software for Intake Distribution Estimate (Iowa State University, 1996). The adjusted data were only used to compare intakes against the DRIs. Since data collection for this study was performed before the release of the 2011 guidelines of the Institute of Medicine, accordingly, vitamin D and cal- cium intake of participants were compared to the both the adequate intake (AI) (19) and the estimated average requirement (EAR) (20). Vitamin and/or mineral supple- ment use and frequency were recorded, however, due to low prevalence of supplement intake, vitamin D or calcium intake reflected only dietary intake. Clinical assessments Venous blood (3 mL) was collected into heparin coated vacutainers followed by centrifugation and storage of plasma at 208C and was then transported on ice packs in coolers to McGill University and stored at 808C until analysis. Height was measured to the nearest 0.1 cm using a portable stadiometer (Road 2 (page number not for citation purpose) Citation: Int J Circumpolar Health 2012, 71: 18999 - http://dx.doi.org/10.3402/ijch.v71i0.18999