Unless all the respondents in the original sample complete all phases of a longitudinal design,there is a possible problem due to
A)selection bias.
B)projected data.
C)attrition.
D)data erosion.

Question

Quizplus · Accepted Answer

Attrition refers to the dropout or loss of participants over time in a longitudinal study. This can potentially bias the results if the participants who drop out are systematically different from those who remain in the study. Therefore, attrition is a possible problem in a longitudinal design if not all respondents complete all phases. A, B, and D are not as relevant or accurate as explanations.

Unless All the Respondents in the Original Sample Complete All