The development and psychometric evaluation of a new instrument to market healthy breakfast and snacks among adolescents.

Abstract

The consumption of non-nutritious snacks instead of a proper breakfast is becoming more widespread among adolescents. It is expected that using the 4P (product, price, place, promotion) strategies of the social marketing (SM) model can help to better identify factors affecting healthy breakfast and snack consumption. The objective of this study was to develop and evaluate the psychometric properties of the Healthy Breakfast and Snack Consumption Scale (HBSCS) using the SM model. This was a cross-sectional descriptive study that was conducted in 2017. First, a scale was developed using the results of a qualitative research based on the SM model. Then, its face, content and construct validities as well as its reliability were assessed. Construct validity was evaluated via exploratory factor analysis conducted on a random sample of 300 high school pupils selected from five girls' schools located in Isfahan, Iran, using the multistage cluster sampling method. Exploratory factor analysis was performed using the methods of principle components extraction and varimax rotation with eigenvalues greater than 1. A four-factor structure that explained 61.73% of the total variance of the HBSCS included healthy breakfast and snack preferences, readiness to pay the price, place preferences and communication channel preferences. Items with an impact score of less than 1.5 were removed. Additionally, items with content validity ratio values of less than 0.62 and content validity index values of less than 0.79 were deleted. The Kaiser-Meyer-Olkin measure value was 0.74 [chi-squared (χ2) = 2353.622; p-value < 0.001]. The Cronbach's α values of the scale and its four dimensions were 0.71 and 0.56-0.72, respectively. This scale has acceptable validity and reliability. School authorities and health professionals can use this scale to screen adolescents at risk of consuming unhealthy foods and snacks. Besides, the scale might be used as a framework for assessing, implementing and promoting healthy eating behaviors among pupils.