Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom.
Ministry of Health, Riyadh, Saudi Arabia.
PLoS One. 2021 Nov 30;16(11):e0260748. doi: 10.1371/journal.pone.0260748. eCollection 2021.
Recorded serum 25(OH)D in survey data varies with observed and unobserved respondent characteristics. The aim of this study was to expose latent population sub-groups and examine variation across groups regarding relationships between serum 25(OH)D and observable characteristics.
This study explored the role of unobserved heterogeneity on associations between surveyed 25(OH)D and various factors using a sample (n = 2,641) extracted from the Saudi Health Interview Survey (2013). Linear regression and finite mixture models (FMM) were estimated and compared. The number of latent classes in the FMM was chosen based on BIC score.
Three latent classes were identified. Class I (39.82%), class II (41.03%), and class III (19.15%) with mean 25(OH)D levels of 22.79, 34.88, and 57.45 ng/ml respectively. Distinct patterns of associations with nutrition, behaviour and socio-demographic variables were recorded across classes that were not revealed in pooled linear regression.
FMM has the potential to provide additional insights on the relationship between 25(OH)D levels and observable characteristics. It should be more widely considered as a method of investigation in this area.
调查数据中记录的血清 25（OH）D 因观察到和未观察到的受访者特征而异。本研究旨在揭示潜在的人群亚组，并检查血清 25（OH）D 与可观察特征之间的关系在各亚组之间的变化。
本研究使用从沙特健康访谈调查（2013 年）中提取的样本（n=2641），探讨了未观察到的异质性对调查 25（OH）D 与各种因素之间关联的作用。使用线性回归和有限混合模型（FMM）进行了估计和比较。根据 BIC 评分选择 FMM 中的潜在类别数。
确定了三个潜在类别。第 I 类（39.82%）、第 II 类（41.03%）和第 III 类（19.15%）的平均 25（OH）D 水平分别为 22.79、34.88 和 57.45ng/ml。在整个线性回归中未揭示的类别中，记录了与营养、行为和社会人口统计学变量的关联模式，这些模式在各个类别之间存在明显差异。
FMM 有可能提供有关 25（OH）D 水平与可观察特征之间关系的更多见解。它应该更广泛地被视为该领域研究的一种方法。
