Publicación:
Handling missing values in interrupted time series analysis of longitudinal individual-level data

dc.contributor.author Bazo-Alvarez J.C. es_PE
dc.contributor.author Morris T.P. es_PE
dc.contributor.author Pham T.M. es_PE
dc.contributor.author Carpenter J.R. es_PE
dc.contributor.author Petersen I. es_PE
dc.date.accessioned 2024-05-30T23:13:38Z
dc.date.available 2024-05-30T23:13:38Z
dc.date.issued 2020
dc.description.abstract Background: In the interrupted time series (ITS) approach, it is common to average the outcome of interest at each time point and then perform a segmented regression (SR) analysis. In this study, we illustrate that such ‘aggregate-level’ analysis is biased when data are missing at random (MAR) and provide alternative analysis methods. Methods: Using electronic health records from the UK, we evaluated weight change over time induced by the initiation of antipsychotic treatment. We contrasted estimates from aggregate-level SR analysis against estimates from mixed models with and without multiple imputation of missing covariates, using individual-level data. Then, we conducted a simulation study for insight about the different results in a controlled environment. Results: Aggregate-level SR analysis suggested a substantial weight gain after initiation of treatment (average short-term weight change: 0.799kg/week) compared to mixed models (0.412kg/week). Simulation studies confirmed that aggregate-level SR analysis was biased when data were MAR. In simulations, mixed models gave less biased estimates than SR analysis and, in combination with multilevel multiple imputation, provided unbiased estimates. Mixed models with multiple imputation can be used with other types of ITS outcomes (eg, proportions). Other standard methods applied in ITS do not help to correct this bias problem. Conclusion: Aggregate-level SR analysis can bias the ITS estimates when individual-level data are MAR, because taking averages of individual-level data before SR means that data at the cluster level are missing not at random. Avoiding the averaging-step and using mixed models with or without multilevel multiple imputation of covariates is recommended. © 2020 Bazo-Alvarez et al.
dc.description.sponsorship Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecyt
dc.identifier.doi https://doi.org/10.2147/CLEP.S266428
dc.identifier.scopus 2-s2.0-85092358260
dc.identifier.uri https://hdl.handle.net/20.500.12390/2624
dc.language.iso eng
dc.publisher Dove Medical Press Ltd
dc.relation.ispartof Clinical Epidemiology
dc.rights info:eu-repo/semantics/openAccess
dc.rights.uri https://creativecommons.org/licenses/by-nc/3.0/
dc.subject Segmented regression
dc.subject Big data es_PE
dc.subject Electronic health records es_PE
dc.subject Interrupted time series analysis es_PE
dc.subject Missing data es_PE
dc.subject Mixed effects models es_PE
dc.subject Multiple imputation es_PE
dc.subject.ocde http://purl.org/pe-repo/ocde/ford#3.01.01
dc.title Handling missing values in interrupted time series analysis of longitudinal individual-level data
dc.type info:eu-repo/semantics/article
dspace.entity.type Publication
oairecerif.author.affiliation #PLACEHOLDER_PARENT_METADATA_VALUE#
oairecerif.author.affiliation #PLACEHOLDER_PARENT_METADATA_VALUE#
oairecerif.author.affiliation #PLACEHOLDER_PARENT_METADATA_VALUE#
oairecerif.author.affiliation #PLACEHOLDER_PARENT_METADATA_VALUE#
oairecerif.author.affiliation #PLACEHOLDER_PARENT_METADATA_VALUE#
Archivos