Background: Dairy products are globally consumed and recommended in dietary guidelines around the world, but their effect on mortality is still controversial. Limited sample size and inconsistent control of adjustment factors make the evidence far from robust. Moreover, the use of relative risk (RR) as a merge indicator might result in information loss of survival analyses in prospective cohort studies.
Objectives: To examine the association of dairy intake and risk of mortality.
Methods: The target question was being assessed at PROSPERO: the association between dairy intake and risk of mortality: a dose–response meta-analysis of prospective cohort studies (CRD161807). A comprehensive search will be performed in the following databases without time limit for publication: PubMed and EMBASE. Prospective cohort studies which have studied the association between dairy intake and risk of mortality will be included. Two review authors will independently select citations for inclusion, extract data and assess the methodological quality. Any disagreement will be resolved by the third review author. Stata 15 will be used for data synthesis and exploring the dose-response relationship between dairy intake and risk of mortality. Piecewise linear regression model and restricted cubic spline model will be used for linear and nonlinear trend estimation respectively. Subgroup analysis will be undertaken on gender, types of dairy intake and risk of mortality. Also, sensitivity analysis will be performed to evaluate stability of the research results.
Results: This study is ongoing, and will be submitted to a peer-reviewed journal for publication.
Patient or healthcare consumer involvement: There was no patient or healthcare consumer in this project.