Sampling

LEVANTE follows an accelerated longitudinal design. The target age range is 2-12 years so children should be ages 2:0 - 10:0 years at time of enrollment.

Participants will subsequently be re-evaluated annually for a minimum of 2 follow-up evaluations per child (3 total time points) and up to age 12:0 years.

This longitudinal data collection is a critical part of the value of the LEVANTE dataset. Individual LEVANTE awards are intended to support a minimum of three “waves” of testing (initial evaluation and two follow-ups).

Sites should understand how sampling and recruitment strategy relates to a broader population of interest. Samples need not be probability samples (and hence need not be representative samples of the population), but they should be compared in their anticipated sociodemographic characteristics to the population of interest.

There is no minimum sample size for participation in LEVANTE. Sites will vary widely in the sample sizes required for their own research questions and the resources available for recruitment and administration. If sites intend to make group comparisons or to test interventions, samples should be planned to provide appropriate statistical power and/or precision for these analyses.