1. Figure 1. Distribution of 25-hydroxyvitamin D (25(OH)D) levels at the baseline visit in a study population of adults aged 18–59 years (n = 309), Toronto, Ontario, Canada, 2009–2013.
From: Predictors of 25-Hydroxyvitamin D Concentration Measured at Multiple Time Points in a Multiethnic Population
Am J Epidemiol. 2017;186(10): doi: /aje/kwx180
Am J Epidemiol | © The Author(s) Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please

2. Figure 2. Distribution of the difference between the highest and lowest 25-hydroxyvitamin D (25(OH)D) concentrations in adults aged 18–59 years with 5 or 6 study visits across the course of a year (n = 219), Toronto, Ontario, Canada, 2011–2013.
From: Predictors of 25-Hydroxyvitamin D Concentration Measured at Multiple Time Points in a Multiethnic Population
Am J Epidemiol. 2017;186(10): doi: /aje/kwx180
Am J Epidemiol | © The Author(s) Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please

3. Figure 3. Baseline versus average 25-hydroxyvitamin D (25(OH)D) concentrations in adults aged 18–59 years with 5 or 6 study visits across the course of a year (n = 219), Toronto, Ontario, Canada, 2011–2013. Pearson correlation: r = 0.88.
From: Predictors of 25-Hydroxyvitamin D Concentration Measured at Multiple Time Points in a Multiethnic Population
Am J Epidemiol. 2017;186(10): doi: /aje/kwx180
Am J Epidemiol | © The Author(s) Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please