Arguing that reliable and valid dropout rate estimates are prerequisite to establishment of causal factors and intervention programs, this article examines differences in definitions of dropouts, computational methods, and the complexities in defining cohorts, as well as the importance of sample attrition. Several sources of error are discussed.…

Guidelines for the implementation of qualitative methods in special education research are offered, addressing rigor, sample selection, data collection, and data management/analysis. Five possible pitfalls are identified, including the quantitative-qualitative methods debate, premature data collection, the tendency to use a linear procedural…

From a priori and post hoc data collection perspectives, this paper describes the interrelations among (1) power, alpha, effect size, and sample size for hypothesis testing; and (2) precision, confidence, and sample size for interval estimation. Implications for special education researchers working with convenient samples of fixed size are…

Five criteria are proposed for evaluating performance in research studies: the directness of sampling, the responsiveness of the target, the reliability of the observers, the frequent assessment of the target during the intervention period, and the critical nature of the target. A case study illustrates effectiveness of the criteria. (Author/CR)

These three newsletters focus on advances and challenges in disability research. The first issue focuses on the results of a survey that investigated how many consumers with disabilities had a computer available in their home and their Internet use. The study involved administrators of Independent Living Centers (ILC) and ILC consumers. Findings…

The extent to which students with disabilities are represented in national data collection programs was investigated by reviewing nine such programs that are receiving attention in current educational reform initiatives. Results suggest that 40-50% of students with disabilities are excluded from these prominent data collection programs. (SLD)

Recent investigations of the extent to which students with disabilities are allowed to participate in major national data collections used in measurement-driven education reform suggest that 40 to 50 percent of students with disabilities are typically excluded from major assessments, although they are included to a greater degree in assessments…