Anonymous questionnaires are frequently used in research with adolescents in order to obtain sincere answers about sensitive topics. Most longitudinal studies include self-generated identification codes (SGICs) to match information. Typical elements include a combination of letters and digits from personal data. However, these data may make the…

Prospective longitudinal data collection is an important way for researchers and evaluators to assess change. In school-based settings, for low-risk and/or likely-beneficial interventions or surveys, data quality and ethical standards are both arguably stronger when using a waiver of parental consent--but doing so often requires the use of…

The present study tested the possibility of operationalizing levels of knowledge acquisition based on Vygotsky's theory of cognitive growth. An assessment tool (SAM-Math) was developed to capture a hypothesized hierarchical structure of mathematical knowledge consisting of procedural, conceptual, and functional levels. In Study 1, SAM-Math was…

Multiple matrix designs are commonly used in large-scale assessments to distribute test items to students. These designs comprise several booklets, each containing a subset of the complete item pool. Besides reducing the test burden of individual students, using various booklets allows aligning the difficulty of the presented items to the assumed…

The practice of screening students to identify behavioral and emotional risk is gaining momentum, with limited guidance regarding the frequency with which screenings should occur. Screening frequency decisions are influenced by the stability of the constructs assessed and changes in risk status over time. This study investigated the 4-year…

Observational methods are increasingly being used in classrooms to evaluate the quality of teaching. Operational procedures for observing teachers are somewhat arbitrary in existing measures and vary across different instruments. To study the effect of different observation procedures on score reliability and validity, we conducted an experimental…