Transient error or specificity? An alternative to the staggered equivalent split-half procedure.

The data-based partial and complete reliability coefficients defined by G. Becker (2000) in his staggered equivalent split-half procedure (SESHP) were compared with the model-based specificity and consistency reliability coefficients defined by R. Steyer, M. J. Schmitt, and M. Eid (1999) in their latent state-trait model (LSTM). Partial reliability is based on coefficient alpha, which contains transient error. State and trait anxiety, measured using the State-Trait Anxiety Inventory on 2 occasions among French adults, illustrated both approaches. Theoretical and empirical analyses demonstrated that the specificity and consistency coefficients offer a testable alternative to the SESHP coefficients. In addition, dynamics of the state residual variance could be modeled and estimated in LSTM.