Appendix L. Condition-Specific Measures of Adult Quality Of Life, Additional Analysis.

Respondents were asked to complete a health-related quality of life scale appropriate to their self-reported food hypersensitivity:

• Food Allergy Quality of Life Questionnaire (FAQLQ) for food allergy.
• Food Intolerance Quality of Life Questionnaire (FIQLQ) for food intolerance.
• Coeliac Disease Quality of Life scale (CDQoL) for coeliac disease. 

The FAQLQ and FIQLQ are rated on a scale from 1 (least impairment on quality of life) to 7 (maximal impairment on quality of life). 

The CDQ is rated on a five-point scale, with the 20 items scores summed – having a range of 20-100.

Each scale consists of food hypersensitivity specific subscales. 

For those completing the FAQLQ, these are: 

• Allergen Avoidance and Dietary Restrictions (AADR), which considers the impact that a restrictive diet has on quality of life and the impact this also has on social activities; 
• Emotional Impact (EI) relating to the worries and concerns about having an allergic reaction or consuming allergens; 
• Risk of Accidental Exposure (RAE), relating to vigilance and awareness needed to avoid ingesting allergens; and 
• Food Allergy related Health (FAH), relating to specific health anxiety about having an allergy or reaction.

For the CDQ, subscales comprise of: 

• limitations, relating to social and dietary limitations of having coeliac disease; 
• Dysphoria, related to negative feelings of having coeliac disease; 
• Health Concerns, concerns about the wider impact having coeliac disease will have on health; and 
• Inadequate treatment, feelings that there are not enough treatment options for the disease.

For the FIQLQ scale, subscales comprise: 

• Emotional Impact (EI), related to the stresses and concerns of having to be aware of foods that could cause a reaction; 
• Social and Dietary restrictions (SDR), related to the impact that having an intolerance has on diet and social activities (for example, eating out); and 
• Reactions and Avoidance (RAv), related to negative feelings about having a reaction (for example, embarrassment and discouragement).

The distribution of the subscales, in aggregate and by characteristics are displayed in this Appendix.

FAQLQ subscales
Table 1.  Summary statistics: FAQLQ Index by domain

Domain	Mean	Std. Dev.	N	min	p25	Median	p75	max
FAQ total	4.76	1.49	385	1.14	3.66	5.1	6	7
FAQ AADR	4.87	1.57	385	1	3.73	5.09	6.18	7
FAQ EI	4.88	1.62	385	1	3.71	5.14	6.29	7
FAQ AE	4.78	1.63	385	1	3.5	5.13	6.13	7
FAQ FAH	4.06	1.63	385	1	3	4	5.33	7

Figure 1. FAQLQ Index by domain

CDQ subscales

Table 2.  Summary statistics: CDQ Index by domain

Domain	Mean	Std. Dev.	N	min	p25	Median	p75	max
CDQ total	48.35	16.91	601	20	34	47	61	95
CDQ Limitations	24.74	9.12	601	9	17	24	31	44
CDQ Dysphoria	6.66	3.1	601	4	4	5	8	19
CDQ Health	12.2	4.61	601	5	9	11	15	25
CDQ Inadequate	4.76	2.51	601	2	2	4	7	10

FIQLQ subscales

Table 3.  Summary statistics: FIQLQ Index by domain

Domain	Mean	Std. Dev.	N	min	p25	Median	p75	Max
FIQ total	4.49	1.53	440	1.06	3.28	4.62	5.72	7
FIQ EI	4.55	1.55	440	1	3.38	4.81	5.75	7
FIQ SDR	4.5	1.69	440	1	3	4.67	6	7
FIQ RA	4.34	1.57	440	1	3	4.5	5.5	7