Turkish version of the ‘food and nutrition literacy questionnaire for Chinese school-age children’ for school-age adolescents: a validity and reliability study

Food literacy and nutrition literacy are important factors that support healthy eating habits. Nutritional literacy is defined as the degree to which individuals have the capacity to acquire, process and understand nutritional knowledge and skills, and the ability to make appropriate decisions about nutrition. In other words, it is the degree to which individuals read and understand nutritional information in order to make appropriate nutritional decisions and gain nutritional skills. Today, a global change is taking place in the food systems. Access to unhealthy foods that are highly processed, low in nutrients and high in energy density is easier than accessing nutritious and healthy foods, which negatively affects diet quality. In this process, the concept of food literacy has gained an important place. Food literacy is expressed as the ability of individuals to make choices in the changing food environment to maintain their diet quality and healthy nutrition. Having a high level of food and nutritional literacy provides the necessary skills and abilities to make the right decision in the current food environment [1‐5].

Food and nutritional literacy ensures that healthy eating practices are supported and sustained. Starting from the pre-school period, supporting food and nutrition literacy in individuals is very important in terms of healthy food choices and nutritional habits. Nutritional habits, starting from the pre-school period and continuing in the adolescence period, are important in terms of non-communicable chronic diseases. Unhealthy diets and insufficient physical activity in adolescence increase the risk of non-communicable diseases by causing excessive weight gain and obesity. This period is a critical period for both childhood and adulthood, and is the best time to develop positive health behaviors that can be sustained throughout life. During this period, energy and nutrient requirements increase. Inadequate intake of macro and micronutrients, unhealthy food choices and dietary habits adversely affect the health, nutritional status and physical and mental development of adolescents [6‐9]. In addition, healthy eating behaviors and a high level of food and nutrition literacy are closely related to academic success in school-age adolescents [10]. In Turkiye, thinness, obesity, vitamin deficiencies, dental caries and anemia are among the most common problems associated with malnutrition [11]. Just at this stage, the importance of food and nutritional literacy in adolescents comes into play. Low food and nutrition literacy hinders the provision of dietary diversity and nutrient adequacy [12].

The acquisition of nutritional literacy skills should start at the earliest possible period in order to create a health culture in the society and to ensure the permanence of healthy behaviours. In addition to nutritional knowledge, skills, knowledge and capacity related to nutrition are also important. There is a need for valid and reliable scales to be used in practices aimed at determining food and nutrition literacy in the whole society and especially in risk groups. Although research in this field is increasing, there is no recognised method that can be used to measure food and nutrition literacy in Turkish children and adolescents. In this study, it was aimed to examine the physiometric characteristics of the scale named ‘Food and Nutrition Literacy Questionnaire for Chinese School-age Children’ in Turkish school age adolescents. We think that the validity and reliability of this scale in Turkish is important in the following ways: 1) This scale takes different dimensions into consideration when measuring nutrition literacy (knowledge and understanding of food and nutrition, access to and planning for food, selecting food, preparing food and eating). 2) This scale provide targets for further nutrition education and intervention 3)This scale focuses not only on the ability to access and understand nutritional information but also on the ability to judge and apply nutritional information, and the ability to communicate and act on that information. We thought that this study will fill the gap in the literature and lead to studies on food and nutrition literacy in adolescents.

While IBM AMOS version 26.0 was used for confirmatory factor analyses, IBM SPSS Statistics for Windows version 26.0 was used for the remaining statistical analyses. A p-value of < 0.05 was considered statistically significant. The reliability and validity were analyzed on the basis of components, not the questions, because some questions assessed more than one component. The relationships between the variables are given with the Pearson correlation coefficient. Chi-square analysis was used to compare qualitative data and detect differences between groups. Mean differences between groups were assessed by independent t-test. Regression analysis was performed for prediction of food and nutrition literacy. One-way ANOVA test was used to evaluate whether there was a statistically significant difference between the means of independent groups.

Food and nutrition literacy defined as a collection of interrelated knowledge, skills and behaviors required to plan, manage, select, prepare and eat foods to meet requirements and determine food intake [20]. Today, healthy dietary behavior describes by nutrition literacy or food literacy. Some researchers have focused on the ability to use food labels effectively [32, 33]. Building these skills and knowledge at a young age is important for skill retention, confidence in food practices and supporting lifelong healthy eating habits [2]. Measuring food and nutrition literacy is a new topic. Existing food and nutrition literacy tools tend to emphasise literacy, numeracy skills and nutrition knowledge, especially in adults. There are limited tools to identify food and nutrition literacy for children and adolescents [2]. Carrol et al. [2] identified tools to assess food and nutrition literacy in children and adolescents and evaluated their psychometric properties in a systematic review. Twelve instruments were included in the study, 6 of which had subscales with either poor or questionable internal consistency scores. Therefore, this suggests that further adaptations may be needed to improve consistency among these instruments [2]. Though research in this area is growing, progression is limited by the lack of an accepted method to measure food and nutrition literacy especially in adolescents. This study was conducted to establish the validity and reliability of the Turkish version of FNLQ-SC which was originally developed by Liu [20]. In Turkiye, there is no scale used to evaluate food and nutrition literacy in school-age adolescents. It is thought that this study will fill the gap in the literature and lead to studies on food and nutrition literacy in adolescents.

There are different tools such as Child Food Insecurity Experiences Scale [34], Food and Nutrition Literacy Questionnaire for Chinese School-age Children [20], Food and Nutrition Literacy Assessment Tool [35], Food Literacy Instrument [36] that assess food insecurity and nutrition literacy in children. The level of food and nutrition literacy is one of the ways to understand the reasons for the nutrition-related problems and behaviours of children and adolescents [9]. However, the number of scales available to assess children's nutritional literacy is limited and some of them have psychometric shortcomings [2]. Our results showed that the Turkish version of FNLQ-SC provided high levels of validity and reliability. The original scale consisted of 50 items (questions), 19 core components and 5 dimensions. The dimensions of knowledge and understanding, access to and planning for food, selecting food, preparing food and eating included 15, 5, 5, 10, 15 questions respectively. The overall FNLQ-SC questionnaire had acceptable internal consistency (Cronbach’s α = 0.698). The Cronbach’s α coefficients for the five dimensions (knowledge and understanding, access to and planning for food, selecting food, preparing food, eating), were 0.452, 0.300, 0.244, 0.148, and 0.436, respectively [20]. EFA was performed to determine the structure of the Turkish version of FNLQ-SC. EFA indicated that the FNLQ-TSC had three factorial structures that accounted for 33.14% of the total variance. However, six components (component 2, 7, 9, 10, 13, and 16) loaded on more than one factor and the difference between these factor loading values was less than 0.10. Therefore, these components were excluded from the scale by considering them as overlapping components, and the EFA analysis was re-run. EFA indicated that the FNLQ-TSC had three factorial structures (Fig. 1) that accounted for 42.0% of the total variance. The Cronbach’s α values for internal consistency were 0.679, 0.581, 0.551, and 0.350 for the FNLQ-TSC total score, factor-1, factor-2, and factor-3, respectively. FNLQ-TSC questionnaire had acceptable internal consistency. The Pearson correlation coefficients between each component and the overall questionnaire ranged from 0.134 to 0.430. The dimensional structure of the FNLQ-TSC obtained in the EFA was controlled by CFA. The three-factor model (Fig. 2) showed acceptable goodness-of-fit indices. (χ2/df = 1.924, RMSEA = 0.052, CFI = 0.864, GFI = 0.949). The correlation coefficients between each dimension and the overall questionnaire ranged from 0.300 to 0.842, especially the coefficients of factor-1 and factor-3, were more than 0.6, which showed a strong correlation with the overall questionnaire (Table 4).

The Turkish version of FNLQ-SC showed positive correlations with age, grade of class and discussion nutrition information with families, and negative correlation being only child. Gender was also an important variable affecting FNLQ-SC scores. Our findings are consistent with studies showing that nutritional literacy is associated with age, gender, education level, number of children and parental education level [20, 37]. The increase in nutritional literacy with age may be due to an increased interest in nutrition and health information and increased exposure to it [38]. Also younger children are not expected to develop the same level of complex skills as older teens or adults [35]. Many studies have shown that girls' nutritional literacy is higher than boys' [12, 39, 40]. This result may be a result of girls' higher interest in nutritional value and healthy nutrition [41] and their awareness that nutrition is an important component of health. Girls felt more empowered than boys to choose and control food and dietary choices, but may be less empowered to actually do so [42]. Parents education level and nutrition literacy, which may be an important educational target for improving child food and nutrition literacy. There were higher food and nutrition literacy among school-age adolescents who had a high father's education level, discussed nutrition information with their family in this study. Home food environment was significantly correlated with children’s food and nutrition literacy [20]. Parents can be role models in accessing and interpreting food and nutrition information, and in teaching children how to critically analyze the credibility and validity of information that shapes their nutritional knowledge [10, 43]. We also found a moderately positive and statistically significant relationship between the FNLQ-TSC total score and the HEI-2015 total score. Consistent with our results, studies showed that higher food literacy and nutrition were positively associated with healthier diet quality in children and adolescents [1, 44, 45]. Food and nutrition literacy questionnaires included many dimensions of food and nutrition knowledge; understanding, access, selection, preparation of food and healthy eating [46]. So food and nutrition literacy may significantly predict diet quality and nutrient density in adolescents (47).

Nevertheless, there are some limitations to our study. The relatively small sample size was one of the limitations of this study. Generalizability of study results may be limited to populations in similar areas with similar demographics. More factors that may affect the nutritional literacy of children and adolescents could have been considered. For example, it was not asked whether children had received any education about nutrition or foods. Nonetheless, we believe that the present study may shed light on future studies.

The results suggested an acceptable validity and reliability of the Turkish version of FNLQ-SC questionnaire to measure food and nutrition literacy in school aged adolescents in Turkiye. And also the Turkish version of FNLQ-SC was significantly correlated with age, gender, grade of class, being an only child, discussing nutrition information with families and diet quality. It can be used to evaluate food and nutrition literacy in similar settings and age groups.