Methods to develop and evaluate attitudinal scales to measure farmer perceptions: Using sheep scab as an example.

Area of Science:

• Veterinary Science
• Agricultural Science
• Social Science Research Methods

Background:

• Limited understanding exists regarding British sheep farmers' attitudes and opinions on sheep scab prevention and management.
• Attitudes, as latent traits, require indirect measurement using validated scales, which are often unevaluated in veterinary research.
• Sheep scab remains a significant concern in sheep farming, necessitating research into farmer perceptions for effective control strategies.

Purpose of the Study:

• To identify and assess latent traits influencing sheep scab control among British sheep farmers.
• To evaluate the performance of attitudinal measurement scales using exploratory factor analysis (EFA) and item response theory (IRT).
• To provide insights into factors affecting sheep scab management and the psychometric properties of relevant survey scales.

Main Methods:

• An online survey distributed to 726 British sheep farmers (725 usable responses) in October 2021.
• Inclusion of 37 belief statements, adapted from prior research, to capture farmer attitudes towards sheep scab management.
• Application of exploratory factor analysis (EFA) for initial scale assessment, followed by item response theory (IRT) for in-depth evaluation using graded response models.

Main Results:

• Exploratory factor analysis indicated that the attitudinal scales performed reasonably well.
• Item response theory analysis demonstrated the scales' ability to differentiate respondents based on perceptions of control, responsibility, trust, and luck.
• Graphical evaluation of graded response models confirmed the utility of the scales in distinguishing farmer attitudes.

Conclusions:

• The study identified crucial factors influencing sheep scab management, including perceptions of control, responsibility, trust, and luck.
• The research underscores the importance of rigorously evaluating attitudinal scales, beyond EFA, for their psychometric performance in research.
• Findings contribute to a better understanding of farmer attitudes, informing future strategies for sheep scab control and the development of validated measurement tools.