Behavioral data are increasingly collected over the Internet. This is particularly useful when participants’ own computers can be used as they are, without any modification that relies on their technical skills. However, the temporal accuracy in these settings is generally poor, unknown, and varies substantially across different hard- and software components. This makes it dubious to administer time-critical behavioral tests such as implicit association, reaction time, or various forms of temporal judgment/perception and production. Here, we describe the online collection and subsequent data quality control and adjustment of reaction time and time interval production data from 7127 twins sourced from the Swedish Twin Registry. The purposes are to (1) validate the data that are already and will continue to be reported in forthcoming publications (due to their utility, such as the large sample size and the twin design) and to (2) provide examples of how one might engage in post-hoc analyses of such data, and (3) explore how one might control for systematic influences from specific components in the functional chain. These possible influences include the type and version of the operating system, browser, and multimedia plug-in type
Correction and Validation of Time-Critical Behavioral Measurements over the Internet in the Stage Twin Cohort with More Than 7000 Participants