Preference reversals in grading systems for retail food facilities.

The authors asked 120 university students about their willingness to dine in restaurants if those restaurants had received inspection grades of A, B, or C under three different scenarios: 1) the restaurant is one they normally dine in, 2) the restaurant has been closed for health violations but recently reopened, and 3) the restaurant has been given a score (88, 78, 68, or 58) but no grade. Using a paired-samples sign test, the authors discovered differences among the scenarios with statistical significance above 99.9 percent. Subjects were less willing to dine if a restaurant had been recently closed and were more willing to dine if only scores were given. The results indicate three cases of preference reversal from the normal order of A, B, and C: 1) subjects preferred a grade of B over A if the B restaurant had a score of 88 and the A restaurant had recently been closed; 2) subjects preferred a grade of C over B if the C restaurant had a score of 78 and the B restaurant had recently been closed; and 3) subjects preferred a score of 68 (which would earn closure in many jurisdictions) over a legitimate grade of C at a recently closed restaurant. In addition, subjects preferred a score of 88 to a grade of B and a score of 78 to a grade of C, even though those scores and respective grades are assumed to be equivalent. The study population was limited to university students, who may not necessarily represent the broader population. Similar cognitive effects have, however, been documented throughout the literature on risk perceptions. In any event, the results indicate a need for closer examination of grading systems. On the basis of preference-reversal principles, the authors propose ways to improve grading systems for retail food facilities and suggest an agenda for further research.