Table 1.

Disability index in inflammatory bowel disease (IBD), the IBD disability index (IBD-DI).³³

	IBD-DI
Categories	Five categories: (1) General health (2) Body functions (3) Body structures (4) Activities and participation (5) Environmental factors
Number of items	27 items 17 items assessing different aspects of disability: 12 were scored on a 5-point Likert score, 2 required a dichotomous answer, 2 required continuous answers, and 1 was divided into three categories Eight items assessing environment interaction with disease Two items assessing access to social security and healthcare system
Scoring	(1) Sum the item values from all selected items to calculate the overall score of the IBD-DI (a higher score indicates a greater level of disability) (2) Rescale all items to range from 0 to 4. Binary items are coded as ‘0’ for ‘no’ and ‘4’ for ‘yes’ (weight loss, arthritis, blood in stools). BMI is scored as ‘0’ for a BMI > 18.5 and ‘4’ for a BMI < 18.5. Number of liquid stools are categorized into quartiles. (3) In case of <20% of missing items for an individual, the total score is then rescaled from 0 to 100 using the following formula: score × 100/(p × 4), where p represents the number of answered items (score is calculated only when at least 80% of items are answered)
Interpretation	Total score ranging from 0 to 100 0–20 (no disability), 20–35 (mild disability), 35–50 (moderate disability) and 50–100 (severe disability)
Recall period	1 week
Application	Designed to be applied by an interviewer A self-reported version may also be developed
Languages	Validated in its French version It needs to be translated for use in other languages and assessing cross-cultural validity

IBD-DI, inflammatory bowel disease disability index; BMI, body-mass index.