A comparison of methods to estimate the survivor average causal effect in the presence of missing data: a simulation study
| Autor: | Robyn H. Guymer, Robert Finger, Amalia Karahalios, Jessica Kasza, Julie A. Simpson, Myra B McGuinness |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Male
Simulation study Epidemiology Principal stratification Iron Missing data Marginal structural model Health Informatics Logistic regression 01 natural sciences Sensitivity and Specificity 010104 statistics & probability 03 medical and health sciences 0302 clinical medicine Sex Factors Bias Covariate Statistics Medicine Humans Computer Simulation 030212 general & internal medicine Unmeasured confounding 0101 mathematics lcsh:R5-920 Models Statistical Survival bias business.industry Macular degeneration Confounding Correction 16. Peace & justice Survival Analysis Diet Causality Death Causal inference Data Interpretation Statistical Propensity score matching Female business lcsh:Medicine (General) Sensitivity analysis Iron Dietary Research Article |
| Zdroj: | BMC Medical Research Methodology BMC Medical Research Methodology, Vol 19, Iss 1, Pp 1-14 (2019) |
| ISSN: | 1471-2288 |
| Popis: | Background Attrition due to death and non-attendance are common sources of bias in studies of age-related diseases. A simulation study is presented to compare two methods for estimating the survivor average causal effect (SACE) of a binary exposure (sex-specific dietary iron intake) on a binary outcome (age-related macular degeneration, AMD) in this setting. Methods A dataset of 10,000 participants was simulated 1200 times under each scenario with outcome data missing dependent on measured and unmeasured covariates and survival. Scenarios differed by the magnitude and direction of effect of an unmeasured confounder on both survival and the outcome, and whether participants who died following a protective exposure would also die if they had not received the exposure (validity of the monotonicity assumption). The performance of a marginal structural model (MSM, weighting for exposure, survival and missing data) was compared to a sensitivity approach for estimating the SACE. As an illustrative example, the SACE of iron intake on AMD was estimated using data from 39,918 participants of the Melbourne Collaborative Cohort Study. Results The MSM approach tended to underestimate the true magnitude of effect when the unmeasured confounder had opposing directions of effect on survival and the outcome. Overestimation was observed when the unmeasured confounder had the same direction of effect on survival and the outcome. Violation of the monotonicity assumption did not increase bias. The estimates were similar between the MSM approach and the sensitivity approach assessed at the sensitivity parameter of 1 (assuming no survival bias). In the illustrative example, high iron intake was found to be protective of AMD (adjusted OR 0.57, 95% CI 0.40–0.82) using complete case analysis via traditional logistic regression. The adjusted SACE odds ratio did not differ substantially from the complete case estimate, ranging from 0.54 to 0.58 for each of the SACE methods. Conclusions On average, MSMs with weighting for exposure, missing data and survival produced biased estimates of the SACE in the presence of an unmeasured survival-outcome confounder. The direction and magnitude of effect of unmeasured survival-outcome confounders should be considered when assessing exposure-outcome associations in the presence of attrition due to death. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink