More broadly speaking, there are limitations in the use of online recruitment when compared with in-person clinical recruitment. Online recruitment methods are limited by demographic representation, biases, and uncertainties. By nature, samples recruited through Web-based methods are not representative of the broader target population . For example, racial and ethnic disparities exist in the accessibility and frequency of computer use in the United States. However, these are minimized when analyzing Internet access via mobile devices . Similarly, those who participate in studies hosted on mTurk tend to be younger, more liberal, and more familiar with Web-based technology . Nevertheless, although mTurk is less representative than Web-based panel services or national probability samples, it may provide a more representative sample of the United States than traditional in-person sampling methods . Online recruitment may also yield lower-quality data as this paper has shown. Accountability and validity are generally more difficult to enforce in online research. Web-based studies tend to rely on self-report, and subjects can more easily provide responses that do not reflect their actual beliefs, values, or behavior. On mTurk, “spammers” and “bots” capitalize on this and find ways to receive rewards offered by a study without successfully completing the intended task  with obvious adverse consequences for the data validity. Inattention and lack of intrinsic motivation may lead to superficial responses and higher attrition rates, although this can be mitigated somewhat by attention checks—supplementary questions and tasks that determine whether a participant is fully paying attention . While the distance between researcher and subject may reduce social desirability bias, Web-based research is not immune from it .