Research Instruments: Validity and Reliability

• Chapter 3 is about data gathering instruments.
• Conclusions drawn in research are only as good as the data collected.
• Appropriate and good research instruments are required for conducting a solid study.

Instrumentation

• Instrument: A general term researchers use for measurement devices like surveys, tests, and questionnaires.
• Instrumentation: The process of developing, testing, and using a measurement device.

Characteristics of a Good Research Instrument

• Concise: A good research instrument is concise but elicits needed data.
• Valid and Reliable: Should pass validity and reliability tests for appropriate and accurate information.
• Sequential: Questions or items must be arranged well for researchers and respondents.
• Easily Tabulated: A factor to consider for quantitative research instruments.
• Ensure variables and research questions are established before crafting instruments.

Validity vs. Reliability

• Validity denotes the extent an instrument measures what it should.
• Reliability denotes the extent an instrument produces similar scores across various conditions, evaluators, and environments.

Data Gathering Techniques for Quantitative Research

• Documentary Analysis: Analyzes secondary sources in churches, schools, public/private offices, hospitals, communities, and city halls.
• Observation: A simple way to collect data directly and unobtrusively.
  • Overt
  • Covert
• Physiological Measures: Uses collection of physical data from subjects.
• Psychological Tests: Includes personality inventories and protective techniques.
  • Personality inventories are self-reported measures assessing differences in traits, needs, or values.
  • Minnesota Multiphasic Personality Inventory (MMPI) is an example.
• Questionnaires: Lists questions about a topic with spaces for responses, answered by multiple people.
  • Questionnaires yield more honest responses
  • Help guarantee confidentiality
  • Minimize bias
  • Help minimize bias based on question-phrasing modes.

Common Scale Types in Questionnaires

• Likert Scale: A scaling technique with declarative statements expressing a viewpoint on a topic, used to measure agreement.
• Semantic Differential Scale: Respondents rate concepts using bipolar adjectives, providing flexibility and ease of construction.

Wording Considerations

• State questions in an affirmative rather than a negative manner.
• Avoid ambiguous questions with words like "many", "always", "usually", and "few".
• Avoid double negative questions.
• Avoid double-barreled questions, i.e. avoid asking two questions in one.