Qualitative and Quantitative Research

• Concepts are the building blocks of theories, which are systematic explanations of some aspect of the real world.
• The dependent variable is the behavior, charac teristic, or outcome the researcher is interested in understanding, explaining, predicting, or affecting.
• The independent variable is the presumed cause of, antecedent to, or influence on the dependent variable.
• Groups that are highly varied with respect to some attribute are described as heterogeneous; groups with limited variability are described as homogeneous.
• A conceptual definition elucidates the abstract or theoretical meaning of the concepts being studied.
• An operational definition is the speci f ication of the procedures and tools required to measure a variable.
• Data —the information collected during the course of a study—may take the form of narra tive information (qualitative data) or numeric values (quantitative data).
• Reliability refers to the accuracy and consistency of information obtained in a study.
• Validity is a more complex concept that broadly concerns the soundness of the study’s evidence—that is, whether the findings are cogent, convincing, and well grounded.
• Trustworthiness

  • Dependability refers to evidence that is believ able, consistent, and stable over time.
  • Confirmability refers to evidence of the researcher’s objectivity.
  • Credibility is achieved to the extent that the research methods engender confidence in the truth of the data and in the researchers’ interpretations of the data.
• Triangulation, the use of multiple sources or referents to draw conclusions about what con stitutes the truth, is one approach to establishing credibility.
• A bias is an influence that produces a distortion in the study results.
• Systematic bias results when a bias is consistent or uniform across study participants or situations.
• For a quantitative researcher, a powerful tool to eliminate bias concerns randomness —having certain features of the study established by chance rather than by design or personal preference.
• Generalizability is the criterion used in a quan titative study to assess the extent to which the f indings can be applied to other groups and set tings.
• A similar concept in qualitative studies is transferability, the extent to which qualitative f indings can be transferred to other settings.