The information needed to determine the internal and external validity of an experimental study is discussed. Internal validity is the degree to which a study establishes the cause-and-effect relationship between the treatment and the observed outcome. Establishing the internal validity of a study is based on a logical process. For a research report, the logical framework is provided by the rep...

background: visualattention is known as acritical base for learning.thepurpose of the present study was to design, develop and evaluate the test-retest and internal consistency reliability as well as face, content and convergent validity of thecomputer- based selective visual attention test (sevat) for healthy first-grade school children.   methods :in thefirst phase of this study,the computer-...

BACKGROUND Validity evidence based on the internal structure of an assessment is one of the five forms of validity evidence stipulated in the Standards for Educational and Psychological Testing of the American Educational Research Association, American Psychological Association, and National Council on Measurement in Education. In this paper, we describe the concepts underlying internal structu...

The goal of gerontological nursing research is to improve the health and well-being of older adults. Yet, a variety of critics have faulted this and other health care research for failing to influence public health policy and decision making. Research, critics say, has produced conflicting findings and esoteric reports that are not useful to public policy makers or clinicians. The conditions un...

dvances in clinical psychology critically depend on methods researchers use for investigating the causal relationships among variables. Research questions commonly include issues about the putative mechanisms associated with various forms of psychopathology (e.g., do dysfunctional beliefs cause depression?) and questions about the effects of treatments (e.g., does cognitive therapy cause a grea...

I participated with pleasure in discussions on 30 September 2011 in Warsaw during the ‘Diff erences in Health in the Polish population’ Conference, which aimed at critical assessment of fi rst baseline results from the PONS study, a pilot prospective cohort established in Poland. Th e PONS study results from the ‘Closing the Health Gap’ Report recommending an attempt to start building in Centra...