Design and development of food safety knowledge and attitude scales for consumer food safety education.

OBJECTIVE: The objective of this study was to design and develop food safety knowledge and attitude scales based on food-handling guidelines developed by a national panel of food safety experts.

DESIGN: Knowledge (n=43) and attitude (n=49) questions were developed and pilot-tested with a variety of consumer groups. Final questions were selected based on item analysis and on validity and reliability statistical tests.

SUBJECTS/SETTING: Knowledge questions were tested in Washington State with participants in low-income nutrition education programs (pretest/posttest n=58, test/retest n=19) and college students (pretest/posttest n=34). Attitude questions were tested in Ohio with nutrition education program participants (n=30) and college students (non-nutrition majors n=138, nutrition majors n=57).

STATISTICAL ANALYSES PERFORMED: Item analysis, paired sample t tests, Pearson's correlation coefficients, and Cronbach's alpha were used.

RESULTS: Reliability and validity tests of individual items and the question sets were used to reduce the scales to 18 knowledge questions and 10 attitude questions. The knowledge and attitude scales covered topics ranked as important by a national panel of experts and met most validity and reliability standards. The 18-item knowledge questionnaire had instructional sensitivity (mean score increase of more than three points after instruction), internal reliability (Cronbach's alpha >.75), and produced similar results in test-retest without intervention (coefficient of stability=.81). Knowledge of correct procedures for hand washing and avoiding cross-contamination was widespread before instruction. Knowledge was limited regarding avoiding food preparation while ill, cooking hamburgers, high-risk foods, and whether cooked rice and potatoes could be stored at room temperature. The 10-item attitude scale had an appropriate range of responses (item difficulty) and produced similar results in test-retest ( P
CONCLUSIONS: Uses for the knowledge questionnaire include assessment of subject matter knowledge before instruction and knowledge gain after instruction. The attitude scale assesses an outcome variable that may predict food safety behavior.