NURS 345 Nursing Research - Session 9: Validity & Reliability

NURS 345 Nursing Research - Session 9: Validity and Reliability

• Reliability and validity are concepts used to evaluate the quality of data collected in research. They measure how well a method, technique, or test measures something.
• Reliability measures the consistency of a measurement; validity measures accuracy.
• In quantitative research, reliability and validity are used to assess accuracy, while the concept of rigor applies to qualitative research to assess the trustworthiness of findings.
• The objectives of this session include examining reliability and validity concepts and discussing the trustworthiness (rigor) of qualitative research.
• The topics covered include validity and reliability, and research rigor.
• Reading material includes chapters 14 from Polit & Beck (2014), and chapter 3 in Grove, Burns, & Gray (2014).

Quantitative Research

• Quantitative research focuses on gathering numerical data to explain phenomena and generalize across groups. It involves systematic investigation of phenomena through quantifiable data using statistical, mathematical, or computational techniques.
• Its aim is to quantify attitudes, opinions, behaviors, and other variables; and generalize results from large sample populations.

Reliability in Quantitative Research

• Reliability refers to the consistency of a measurement method.

• A reliable measurement provides the same result when repeated under similar conditions.

• Examples include a thermometer providing consistent temperature readings under identical conditions. Conversely, a symptom questionnaire yielding inconsistent diagnoses by different doctors points to low reliability.

• Reliability is crucial for research findings to be considered accurate and replicable.

• Three types of reliability include:

  • Test-retest reliability: consistency of a measurement over time
  • Inter-rater reliability: consistency of a measurement across different observers
  • Internal consistency reliability: consistency of a measurement involving different parts of a test aiming at measuring the same thing.

• Reliability is often measured statistically with a reliability coefficient (e.g., coefficient alpha or Cronbach's alpha), ranging from 0 to 1. Higher values indicate higher internal consistency reliability.

Validity in Quantitative Research

• Validity refers to how accurately a method measures what it intends.

• Validity assesses if a survey measuring depression truly measures depression, rather than anxiety.

• Validity is crucial for drawing meaningful conclusions from research, since an invalid measurement isn't measuring what it intended.

• Validity is the accuracy of measurement, and a valid measurement must be reliable.

• Types of validity in research include:

  • Construct validity: ensures the measured concept is represented by the method.
  • Content validity: evaluates whether a test covers all aspects of its concept (e.g., a stress questionnaire covering various types of stress).
  • Face validity: a subjective measure assessing how suitable a measurement seems to be.
  • Criterion validity: whether a measurement corresponds to other established measures of the same concept.

Assignment

• Students are assigned one-page papers focusing on:

  • Strategies for ensuring reliability and validity in research
  • Factors influencing validity and reliability in research

Rigor (Trustworthiness) in Qualitative Research

• Qualitative research explores phenomena that might not be easily quantified.
• Qualitative methods can identify trends earlier than quantitative methods.
• Rigor in qualitative research refers to the trustworthiness of the findings; this is assessed by factors including credibility, dependability, transferability, and confirmability.
• These criteria are key for establishing the strength of qualitative research and the validity of its conclusions.

Trustworthiness Criteria

• Lincoln and Guba (1986) have developed criteria for qualitative research trustworthiness. These include:

  • Credibility: ensuring the findings represent the truth in the study; ensuring that the findings are consistent with the participants' reality and not a figment of the researcher's imagination.
  • Transferability: Demonstrating the applicability of research findings to other contexts, populations, or phenomena.
  • Dependability: Checking the consistency of the analysis process, ensuring the study can be replicated and similar findings obtained.
  • Confirmability: Ensuring the findings are objective, based on participants' responses, not influenced by the researcher's biases.

Strategies to Ensure Criteria

• These strategies are used to enhance research trustworthiness:

  • Credibility: prolonged engagement, persistent observation, triangulation, member checking.
  • Transferability: thick descriptions.
  • Dependability: audit trail.
  • Confirmability: Use of audit trail, ensuring interpretations are grounded in data, not researcher bias.

Summary

• Reliability is about consistent results achieved using the same methods over time.
• Validity is about the accuracy of the instrument in measuring what is intended.
• Qualitative research trustworthiness is assessed via credibility, dependability, transferability, and confirmability.

References

• Burns, N., Grove, S. K., & Gray, J. (2015). Understanding nursing research: building an evidence-based practice. St. Louis, Missouri: Elsevier.
• Polit, D. F., & Beck, C. T. (2014). Essentials of nursing research: Appraising evidence for nursing practice. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins.
• Lincoln, Y. S., & Guba, E. G. (1986). Qualitative research in education.Sage publications.

Explore the crucial concepts of reliability and validity in nursing research during this session. Understand how these concepts affect the quality and trustworthiness of both quantitative and qualitative studies. This quiz assesses your knowledge on data consistency, accuracy, and research rigor.