Nutritional assessment in inflammatory bowel disease (IBD): development of the Groningen IBD Nutritional Questionnaires (GINQ).

Background
Diet plays a key role in the complex aetiology and treatment of inflammatory bowel disease (IBD). Most existing nutritional assessment tools neglect intakes of important foods consumed or omitted specifically by IBD patients or incorporate non-Western dietary habits, making development of appropriate dietary guidelines for (Western) IBD patients difficult. Hence, we developed a food frequency questionnaire (FFQ), the Groningen IBD Nutritional Questionnaires (GINQ-FFQ); suitable to assess dietary intake in IBD patients.

Methods
To develop the GINQ-FFQ multiple steps (Figure 1) were taken; identification of IBD specific foods, literature search and evaluation of current dietary assessment methods. Expert views were collected and in collaboration with Wageningen University, division of Human Nutrition and Health, this semi-quantitative FFQ was developed using standard methods to obtain a validate questionnaire. Next, the GINQ-FFQ was digitalised into a secure web-based environment which also embeds additional nutritional and IBD-related questions.

Results
The GINQ-FFQ is an online self-administered FFQ evaluating dietary intake over the past month as a proxy of habitual intake of the previous six months. The GINQ-FFQ consists of 121 questions on 218 food items. It takes about 45 min to fill out the GINQ-FFQ.

Conclusion
This paper describes the design process of the GINQ-FFQ which is newly developed to assess dietary intakes especially (but not exclusively) in IBD patients.