Development and Validation of a Brief Instrument to Measure Knowledge About the Energy Content of Meals

Abstract

ObjectiveTo develop and validate a brief scale to assess knowledge about the energy content of meals for adults in Switzerland. MethodsBased on a random sample, the scale was developed using a Rasch model approach. To assess validity and reliability, the model was replicated and scores were compared with another nutrition knowledge measure and with dietitian trainees’ scores. A test-retest was performed. ResultsSurvey studies included 477, 505, and 136 participants from the general population and 59 dietician trainees. The Rasch scale consisted of 11 multiple-choice items ranging from easy to difficult and correlated with general nutrition knowledge (r = .47; P < .001; r2 = .22). Dietitian trainees achieved higher scores (P < .001; d = 2.17) than did people from the general population; test-retest reliability results were r = .73, P < .001, and r2 = .53. Conclusions and ImplicationsResults showed that the scale is efficient, valid, and reliable for use in the general population in Switzerland.