Correction for retest effects across repeated measures of cognitive functioning: a longitudinal cohort study of postoperative delirium

Abstract

[...]the ability to measure or adjust for practice or retest effects is further complicated when there is an acute event or insult that is anticipated to influence test performance, such as major surgery, acute illness, or intervention.[...]correction for retest effects is especially important for descriptive and natural history studies, but for analytical epidemiology studies – for example, characterizing the impact of discrete risk factors (such as delirium, depression, diabetes) – the impact of addressing retest effects is in interpretation and building the narrative to set the context of observed differences and effects of exposures.[...]the retest correction approaches analyzed have been previously studied in various fields and were selected specifically for this study design, but the chosen methods are not an exhaustive list, and it is possible that alternative approaches exist.[...]a gold standard approach for this type of study might be repeated observations prior to the acute event, such that retest effect has been exhausted before the event or insult of interest [44, 59].