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ORIGINAL ARTICLE

Food allergy in adolescents: validation of the food allergy independent measure and the EuroPrevall food allergy quality of life questionnaire into Spanish

Dah-Tay Jang, Laura Ibáñez, Elisa Buendía, María Pérez Sabido, Bartoll Ester, Nieto María, Selva Blanca, Uixera Sonia, Nieto Antonio, Mazón Ángel*

Unit of Pediatric Allergy and Pneumology, Children’s Hospital Health Research Institute La Fe, Valencia, Spain

Abstract

Background: Different questionnaires have been developed globally to assess and compare the impact of food allergy on the quality of life. The aim of this study was to validate a Spanish translation of the Food Allergy Independent Measure (FAIM) and the EuroPrevall Food Allergy–Quality of Life Questionnaire–Teenage Form (FAQLQ-TF) for adolescents aged 13–17 years.

Methods: Sixty adolescents diagnosed with immunoglobulin E-mediated allergy to food completed the questionnaires. Cronbach’s alpha was used to assess internal consistency; correlation between FAQLQ-TF and FAIM was used to test construct validity. The discriminant validity was evaluated by comparison with the number of offending foods, the perceived impact on social life, the diagnosis of anaphylaxis, and the previous prescription of adrenaline auto--injectors (AAI).

Results: No question fulfilled criteria to be removed from the questionnaire. For FAIM, Cronbach’s alpha = 0.763, and for the four domains of FAQLQ-TF, Cronbach’s alpha = 0.797–0.847. A significant correlation existed between FAQLQ-TF and FAIM, and of both of them with anaphylaxis and the prescription of AAI (P ˂ 0.05 for all comparisons).

Conclusions: This Spanish translation of FAIM and FAQLQ-TF for adolescents had good internal consistency and construct validity as well as ability to discriminate patients according to the number of foods to avoid, impact on social life, diagnosis of anaphylaxis, and AAI prescription.

Key words: Adolescents, Food allergy, Quality of life, Questionnaire, Spanish, Teenagers, Validation

*Corresponding author: Angel Mazon. Unit of Pediatric Allergy and Pneumology. Hospital La Fe. Av. Fernando Abril Martorell 106. 46021-Valencia. Spain. Email address: [email protected]

Received 24 February 2022; Accepted 12 November 2022; Available online 1 March 2023

DOI: 10.15586/aei.v51i2.617

Copyright: Jang D-T, et al.
This open access article is licensed under Creative Commons Attribution 4.0 International (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/

Introduction

High prevalence of food allergy has become a global challenge.1 Food allergy has a broad spectrum of severity, from minor sporadic symptoms to severe, life-threatening reactions. Thus, its impact on the quality of life (QoL) is variable, and, in addition to clinical reactions, costs and limitations in everyday life pose further challenges for children and their families.

Education of patients, food challenge tests, and recent procedures, such as desensitization or induction of oral tolerance, can have a favorable impact on QoL,2,3 although they are not always free of risks and can induce high direct and indirect costs.

The EuroPrevall initiative, with financial support from the Framework Programme FP6 of the European Union, had the objective of evaluating several aspects of food allergy in Europe, such as epidemiology, diagnosis, and treatment of food allergy.4 It developed some questionnaires on food allergy to assess and compare QoL across countries with the same tools. Specific questionnaires were developed for children, adolescents, and parents,57 which require to be translated and validated in different languages before use. The aim of our work was to validate into Spanish (Spain) the translation of the Food Allergy Independent Measure (FAIM) and the EuroPrevall Questionnaire on Food Allergy-Quality of Life Teenage Form (FAQLQ-TF) for adolescents aged 13–17 years.

Material and Methods

The English version of both FAQLQ-TF and FAIM6 were translated into Spanish following the same process as done before with the version of the questionnaires for children.8 Briefly, one of the authors, fluent in English and having over 20 years of experience in the evaluation of children and adolescents with food allergy, made the first translation, which was reviewed by other authors, to agree upon the final version. This was back-translated into English by an independent professional bilingual translator. The back-translated version was checked with the original one, and no relevant differences were found; hence, the agreed version was used for the study. A large pilot group of adolescents completed the questionnaires and could understand and answer all the questions (results not included), so the questionnaires were then used for the patients of this study. The translated versions are shown in the online Supplementary Figure S1.

Consecutive adolescents, 13–17-year old, filled in the questionnaires. They had immunoglobulin E (IgE)-mediated food allergy, based on compatible clinical manifestations, on the ingestion of food, together with positive skin prick test and/or serum-specific IgE. During one visit scheduled for a food challenge, before a reaction could occur, the adolescents filled in the questionnaire. For avoiding selection bias, they were invited to participate independent of severity of allergy or the number of offending foods.

The FAQLQ-TF had 23 questions in the following four domains: six questions on allergen avoidance, six on risk of accidental exposure, seven on emotional impact, and four on dietary restrictions.

The FAIM, used to evaluate the construct validity of questionnaires, has been shown to be relevant, reliable, and have face validity to independently measure food allergy.9 It includes four questions on expectation of outcome (EO), the perception of potential reactions after exposure to offending foods, and two questions on independent measures (IM), number of offending foods to avoid, and impact on social activities. The electronic records were reviewed to collect information about the diagnosis of anaphylaxis and the prescription of adrenaline auto-injectors (AAI). The study was approved by the Ethics Committee of the Health Research Institute La Fe (No. 2020-003-1), and results were coded to guarantee anonymity of responders.

The answers to the questions follow a Likert scale, ranging from 0 to 6, with higher values associated to worse QoL. The consistency of FAQLQ-TF domains and FAIM was assessed with Cronbach’s alpha. The corrected item-total correlations and changes in Cronbach’s alpha if an item was deleted were also estimated. The Spearman’s correlation value between the questions of FAQLQ-TF and those of FAIM was calculated. The Mann–Whitney U test was used to compare the values of FAQLQ-TF domains and FAIM depending on the diagnosis of anaphylaxis and previous prescription of AAI. SPSS 15.0, 2006 program (Chicago, Ill, USA) was used for calculations.

Results

Sixty adolescents completed the questionnaires. Their demographic and clinical data are shown in Table 1. They answered all the questions with no blank responses.

Table 1 Demographic and clinical description of participants; numbers (percentage).

Gender Male 35 (58.3) Age (mean and range) 14.7 (13.0–17.2)
Female 25 (41.7)
Age ˂15 years 36 (60) Monoallergic 17 (28.3)
˃15 years 24 (40) Polyallergic 43 (71.7)
Asthma No 35 (58.3) Foods n
Yes 25 (41.7) Milk 3
Anaphylaxis Yes 27 (45.0) Egg 11
No 33 (55.0) Walnut 32
Adrenaline Yes 26 (43.3) Hazelnut 23
No 34 (56.7) Peanut 20
Number of offending foods 1 17 (28.3) Cashew nut 9
2 13 (21.7) Pistachio 11
3 7 (11.7) Kiwi 19
4 3 (5.0) Peach 25
5 8 (13.3) Fish 9
6 3 (5.0) Crustaceans 14
˃6 9 (15.0) Others 52

Table 2 shows the values of Cronbach’s alpha (all values ˃0.7) for FAIM, FAQLQ-TF, and its four domains. Additional measures for each question of FAIM are also shown therein. Specific values for FAQLQ-TF domains are shown in Supplementary Tables S1S4. If the corrected item-total correlation is less than 0.3, or if there is a substantial increase in the Cronbach’s alpha if an item is deleted, the removal of that question is generally recommended.10 This first criterion for removal was observed with FAIM question EO1 (“Chance that you will accidentally eat something to which you are allergic”) that had an item-total correlation value of 0.286. The second -criterion had no specific cut-off point, but if question 10 of FAQLQ-TF (“How troublesome do you find it, because of your food allergy, that you must refuse treats at school or work?”) was deleted, then there would be an increase in Cronbach’s alpha from 0.797 to 0.840. None of the rest of the questions met those criteria.

Table 2 Values of Cronbach’s alpha for the whole Food Allergy Quality of Life Questionnaire–Teenage Form (FAQLQ-TF) and its four domains, and the whole Food Allergy Independent Measure (FAIM) and its questions (EO1–EO4, IM1, and IM2).

No. of questions Cronbach’s alpha Cronbach’s alpha if an item was deleted (range) Corrected item/total correlation (range)
Whole FAQLQ-TF 23 0.937 0.931–0.937 0.443–0.779
Allergen avoidance 6 0.847 0.805–0.845 0.526–0.732
Risk of accidental exposure 6 0.802 0.720–0.796 0.441–0.763
Emotional impact 7 0.804 0.756–0.800 0.415–0.690
Dietary restrictions 4 0.797 0.702–0.840 0.449–0.706
FAIM 6 0.763 0.697–0.778 0.285–0.611
EO1: Chance of accidental exposure - - 0.778 0.285
EO2: Chance of severe reaction - - 0.715 0.551
EO3: Chance of dying - - 0.697 0.611
EO4: Chance of not acting effectively - - 0.739 0.459
IM1: Number of foods to avoid - - 0.713 0.580
IM2: Effect on social life - - 0.713 0.562

Significant correlations were observed between the whole FAQLQ-TF and its domains and the whole FAIM and its six questions (P ˂ 0.05). Further, significant correlations were also discovered when evaluating individual questions of FAQLQ-TF with those of FAIM (Table 3).

Table 3 Correlation (Spearman`s coefficient) of the Food Allergy Quality of Life Questionnaire–Teenage Form (FAQLQ-TF) score and its domains with the Food Allergy Independent Measure (FAIM) score and its questions.

FAQLQ-TF FAIM
Total EO1 EO2 EO3 EO4 IM1 IM2
Total 0.734*** 0.475*** 0.502*** 0.489*** 0.417** 0.674*** 0.601***
Allergen avoidance 0.67*** 0.61*** 0.40** 0.33* 0.43** 0.61*** 0.52***
4 Read labels 0.42** 0.36** 0.34** 0.21 0.39** 0.22 0.35**
6 Stay for a meal 0.63*** 0.55*** 0.38** 0.31* 0.37** 0.60*** 0.54***
7 Try fewer 0.26* 0.01 0.08 0.07 0.16 0.36** 0.38**
8 Check yourself 0.56*** 0.32* 0.35** 0.38** 0.47*** 0.45*** 0.39**
9 Hesitate eating 0.53*** 0.63*** 0.39** 0.20 0.31* 0.39** 0.30*
16 Explain people 0.26* 0.40** 0.03 -0.06 0.15 0.33* 0.27*
Risk of accidental exposure 0.68*** 0.45*** 0.48*** 0.45*** 0.34** 0.61*** 0.54***
11 Touching foods 0.45*** 0.14 0.28* 0.35** 0.37** 0.34** 0.48***
13 Ingredients change 0.64*** 0.34** 0.40** 0.45*** 0.27* 0.65*** 0.60***
14 Label traces of 0.49*** 0.42** 0.42** 0.31* 0.16 0.40** 0.29*
15 Label different 0.34** 0.23 0.37** 0.24 0.16 0.31* 0.29*
17 Others can eat 0.41** 0.33** 0.13 0.20 0.20 0.44*** 0.34**
18 Not take account 0.46*** 0.42** 0.40** 0.30* 0.25 0.34** 0.29*
Emotional impact 0.68*** 0.30* 0.61*** 0.56*** 0.38** 0.56*** 0.48***
5 Less control 0.61*** 0.41** 0.46*** 0.42** 0.28* 0.59*** 0.43**
12 Carry adrenaline 0.43** 0.16 0.33* 0.44*** 0.07 0.49*** 0.33**
19 Allergic reaction 0.50*** 0.12 0.62*** 0.42** 0.39** 0.24* 0.22
20 Eating wrong 0.60*** 0.26* 0.63*** 0.48*** 0.39** 0.27* 0.32*
21 Never before 0.49*** 0.31* 0.40** 0.36** 0.33* 0.48*** 0.34**
22 Discouraging reaction 0.36** 0.26* 0.17 0.23 0.26* 0.30* 0.35**
23 Not taking account 0.33** 0.01 0.37** 0.34** 0.20 0.23 0.33**
Dietary restriction 0.65*** 0.35** 0.32* 0.51*** 0.36** 0.65*** 0.64***
1 Always watching 0.58*** 0.35** 0.41** 0.44*** 0.27* 0.46*** 0.49***
2 Eating fewer things 0.57*** 0.14 0.27* 0.45** 0.35** 0.62*** 0.64***
3 Limited in buying 0.60*** 0.27* 0.33* 0.47*** 0.51*** 0.52*** 0.56***
10 Refuse treats 0.32** 0.34** 0.19 0.29* 0.08 0.45*** 0.39**

Correlation is significant at *0.05, **0.01, and ***0.001 levels.

EO1: chance of accidental exposure; EO2: chance of severe reaction if exposed accidentally; EO3: chance of dying if exposed accidentally; EO4: chance of not acting effectively if exposed accidentally; IM1: number of foods one needs to avoid; IM2: effect of food allergy on social life.

The diagnosis of anaphylaxis and the fact of having been prescribed AAI (Table 4 and Supplementary Table S5) were associated with worse values of the whole FAQLQ-TF and its domains and whole FAIM and its six questions, except for having nearly significant association (P = 0.06) between the prescription of AAI and FAIM question EO4 (“Chance that you cannot effectively deal with an accidental allergic reaction”). Allergy to elemental foods, such as milk and eggs, had significantly worse QoL, and polyallergic patients had worse FAIM values than monoallergic patients (Table 4 and Supplementary Table S6); patient’s age or the presence of asthma was not significant (Table 4). A correlation was observed (P ˂ 0.001) between the values of FAQLQ-TF and its domains and the number of foods that patients felt they had to avoid (Supplementary Table S7). The time elapsed since the last reaction was not significant (P ˃ 0.26 for all questions).

Table 4 Mean rank values of the Food Allergy Quality of Life Questionnaire–Teenage Form (FAQLQ-TF) score and its domains, and Food Allergy Independent Measure (FAIM) score and its questions, according to the diagnosis of anaphylaxis and having been prescribed autoinjectable adrenaline.

Whole FAQLQ-TF FAIM
Mean rank U P Mean rank U P
Anaphylaxis No (n = 33) 21.62 152 ˂0.001 21.55 150 ˂0.001
Yes (n = 27) 41.35 41.44
Adrenaline No (n = 34) 22.50 170 ˂0.001 22.21 160 ˂0.001
Yes (n = 26) 40.96 41.35
Age ˂15 years (n = 36) 29.58 399 0.618 31.03 384 0.73
≥15 years (n = 24) 31.88 29.71
Asthma No (n = 35) 27.59 336 0.126 28.53 369 0.300
Yes (n = 25) 34.58 33.26
Monoallergic vs. polyallergic Monoallergic (n = 17) 24.68 266 0.104 22.50 229 0.025
Polyallergic. (n = 43) 32.80 33.66
Allergic to milk and/or eggs No (n = 12) 28.78 182 0.049 28.44 219 0.201
Yes (n = 48) 39.38 38.75
Allergic to nuts No (n = 20) 25.23 295 0.098 25.28 347 0.405
Yes (n = 40) 33.14 33.11

There was no floor or ceiling effect: none of the patients had the lowest score in the whole FAQLQ-TF and its domains and FAIM and its questions. Only one patient (1.7%) had the highest score for the domain of allergen avoidance, and another patient in FAIM well below the acceptable proportion of 15%.11

Discussion

Validation of common questionnaires in different languages is important to compare food allergy across the world. Versions of questionnaires for children aged 8–12 years and for parents have been already validated in Spanish and other languages.8,12,13 Nevertheless, validation of FAQLQ-TF or other questionnaires14 for adolescents was practically nonexistent in languages other than English, even though adolescents have frequent reactions,15 which impact their QoL. In this study, we aimed to validate FAQLQ-TF and FAIM for adolescents in Spanish.

Values of Cronbach’s alpha for the whole FAQLQ-TF and its four domains were more than 0.79 (values above 0.70 are considered acceptable).16 Likewise, Cronbach’s alpha for FAIM was 0.763. These results demonstrated a good global internal consistency.

Nevertheless, if the question on accepting treats at school or work place was deleted, then Cronbach’s alpha for the domain of dietary restrictions showed a moderate increase from 0.797 to 0.840. The fact that our study was conducted during the COVID-19 pandemic must have affected this domain, as sharing treats at school or work place was prohibited since the beginning of the outbreak; although, this limitation on treats is probably not as important in adolescents as in younger children. One of the FAIM questions (EO1: “Chance of accidental reaction”) showed a corrected item-total correlation of 0.285, intending a low correlation of this question with the summated scores of other questions in FAIM. If the values are less than 0.3 or even 0.4,10 then the removal of the question should be considered, as it may not be measuring the same entity as the others.

The correlation of FAQLQ-TF with independent FAIM was assessed to evaluate the construct validity of the questionnaire.9 We discovered significant correlations between the global scores and the scores of FAQLQ-TF domains. Most, but not all, of the correlations between individual questions of FAQLQ-TF and FAIM questions were significant. While FAIM mostly reflects the severity of food allergy, some of the questions in FAQLQ-TF reflect impact on everyday QoL, and there may be no correlations, as we also found, to a greater extent, in the questionnaires for children aged 8–12 years.8

The discriminant capacity was assessed through several variables. In the validation of both our version and the English version, adolescents who had to avoid more foods demonstrated worse scores in questionnaires.6 We found worse scores for both FAQLQ-TF and FAIM in children with anaphylaxis or having previous prescription of adrenaline. In the validation of the English version, FAQLQ-TF was not able to discriminate between patients with and without anaphylaxis.6 In our case, this association was clear for global scores as well as for all the questions of FAIM; however, it had not been so clear in the questionnaires for children aged 8–12 years,8 may be because of less maturity to understand the consequences of food allergy. Allergy to basic foods, such as milk and eggs, was associated with worse QoL, and polyallergy was linked to worse FAIM; however, these variables did not indicate the same consistency as anaphylaxis or adrenaline prescription. In fact, their significance was mainly driven by only one or two individual questions, and not by all of them as for anaphylaxis or adrenaline prescription.

No ceilings or floor effects were found for questionnaires and domains.11 This finding, together with the significant differences according to anaphylaxis, prescription of adrenaline and number of foods to avoid, support the discriminant ability of the Spanish version.

Some limitations of our study were common with validation in children aged 8–12 yeas.8 We did not perform a comparison of FAQLQ-TF with generic health-related QoL questionnaires. Specific questionnaires are more adequate to evaluate changes in QoL because of food allergy,17,18 and a low agreement has been described between specific and generic questionnaires,18,19 which are recommended, instead, to compare different disorders.17,18 The test-retest reliability was not evaluated either, as the food challenge performed on the day when questionnaires were completed could induce a relevant change in QoL. This potential change on the stability of patient’s condition could invalidate results of the retest. However, excellent reliability has been established for the English version of FAQLQ-TF.6,20

Conclusion

In summary, the Spanish version of both FAQLQ-TF and FAIM has shown good values regarding internal consistency, construct validity, and acceptable discriminant capacity for some clinical variables. Although it has some limitations and some questions require further evaluation, it can be used as a validated questionnaire for QoL in adolescents with food allergy similar to other language versions until better tools are designed.

REFERENCES

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2. Kansen HM, Le TM, Meijer Y, Flokstra-de Blok BMJ, Welsing PMJ, van der Ent CK, et al. The impact of oral food challenges for food allergy on quality of life: A systematic review. Pediatr Allergy Immunol. 2018;29(5):527–37. 10.1111/pai.12905

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9. van der Velde JL, Flokstra-de Blok BM, Vlieg-Boerstra BJ, Oude Elberink JN, DunnGalvin A, Hourihane JO, et al. Development, validity and reliability of the food allergy independent measure (FAIM). Allergy. 2010 May;65(5):630–5. 10.1111/j.1398-9995.2009.02216.x

10. Gliem JA., Gliem RR. Calculating, interpreting, and reporting Cronbach’s alpha reliability coefficient for Likert-type scales. 2003 Midwest Research to Practice Conference in Adult, Continuing, and Community Education, Ohio State University, Columbus, OH [Internet]. [cited 2003]. Available from: https://scholarworks.iupui.edu/bitstream/handle/1805/344/Gliem+&+Gliem.pdf?sequence=1 Accessed March 10, 2022.

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13. Manso L, Pineda R, Huertas B, Fernández-Rivas M, Diéguez MC, Cerecedo I, et al. Validation of the Spanish version of the Food Allergy Quality of Life Questionnaire--Parent Form (S-FAQLQ-PF). J Investig Allergol Clin Immunol. 2017;27(6):363–9. 10.18176/jiaci.0182

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Supplementary

Figure S1 Cuestionario de Calidad de Vida en Alergia Alimentaria—Formulario para adolescentes (13–17 años).

Table S1 Modifications in Cronbach’s alpha for each question in the domain of allergen avoidance (Cronbach’s alpha = 0.847).

Cronbach’s alpha when an item was deleted Corrected item/total correlation
4 Read labels 0.842 0.526
6 Stay for a meal 0.817 0.658
7 Try fewer 0.805 0.718
8 Check yourself 0.819 0.656
9 Hesitate eating 0.805 0.732
16 Explain people 0.845 0.527

Table S2 Modifications in Cronbach’s alpha for each question in the domain of risk of accidental exposure (Cronbach’s alpha = 0.802).

Cronbach’s alpha when an item was deleted Corrected item/total correlation
11 Touching foods 0.779 0.521
13 Ingredients change 0.720 0.763
14 Label traces of 0.770 0.565
15 Label different 0.766 0.580
17 Others can eat 0.796 0.441
18 Not take account 0.787 0.483

Table S3 Modifications in Cronbach’s alpha for each question in the domain of emotional impact (Cronbach’s alpha = 0.804).

Cronbach’s alpha when an item was deleted Corrected item/total correlation
5 Less control 0.776 0.550
12 Carry epipen 0.799 0.460
19 Allergic reaction 0.761 0.643
20 Eating wrong 0.756 0.690
21 Never before 0.756 0.666
22 Discouraged reaction 0.799 0.415
23 Not taking account 0.800 0.418

Table S4 Modifications in Cronbach’s alpha for each question in the domain of dietary restriction (Cronbach’s alpha = 0.797).

Cronbach’s alpha when an item was deleted Corrected item/total correlation
1 Always watching 0.710 0.682
2 Eating fewer things 0.731 0.644
3 Limited in buying 0.702 0.706
10 Refuse treats 0.840 0.449

Table S5 Mean rank of values of the Food Allergy Quality of Life Questionnaire–Teenage Form (FAQLQ-TF) score and domains, and Food Allergy Independent Measure (FAIM) score and questions according to the diagnosis of anaphylaxis and the previous prescription of autoinjectable adrenaline.

Anaphylaxis Autoinjectable adrenaline
No (n = 33) Yes (n = 27) U P No (n = 34) Yes (n = 26) U P
Whole FAQLQ-TF 21.62 41.35 152 ˂0.001 22.50 40.96 170 ˂0.001
Allergen avoidance 23.58 38.96 217 0.001 23.94 39.08 219 0.001
Risk of accidents 22.26 40.57 173 ˂0.001 23.24 40.00 195 ˂0.001
Emotional impact 21.48 41.52 148 ˂0.001 22.10 41.48 156 ˂0.001
Dietary restrictions 22.86 39.83 193 ˂0.001 23.91 39.12 218 0.001
FAIM 21.55 41.44 150 ˂0.001 22.21 41.35 160 ˂0.001
EO1: Chance of accidental exposure 26.17 35.80 302 0.029 25.79 36.65 282 0.014
EO2: Chance of severe reaction 23.18 39.44 204 ˂0.001 24.00 39.00 221 0.001
EO3: Chance of dying 22.12 40.74 169 ˂0.001 22.96 40.37 185 ˂0.001
EO4: Chance of not acting effectively 26.11 35.87 300 0.028 26.87 35.25 318 0.060
IM1: Number of foods to avoid 23.91 38.56 228 0.001 23.69 39.40 210 ˂0.001
IM2: Effect on social life 24.29 38.09 240 0.002 24.71 38.08 245 0.002

Table S6 Mean rank of values of the Food Allergy Quality of Life Questionnaire–Teenage Form (FAQLQ-TF) score and its domains, and Food Allergy Independent Measure (FAIM) score and its questions according to polyallergy and allergy to milk and eggs.

Allergy to milk and/or eggs Polyallergic
No (n = 48) Yes (n = 12) U P No (n = 34) Yes (n = 26) U P
Whole FAQLQ-TF 28.28 39.38 182 0.049 26.48 32.80 267 0.104
Allergen avoidance 27.92 40.83 164 0.022 26.03 32.27 290 0.212
Risk of accidents 29.04 36.33 218 0.195 26.53 32.07 293 0.268
Emotional impact 28.74 37.54 203 0.118 25.79 32.36 286 0.189
Dietary restrictions 27.43 42.79 140 0.006 23.82 33.14 252 0.062
FAIM 28.44 38.75 189 0.067 22.50 33.66 230 0.025
EO1: Chance of accidental exposure 28.26 39.46 181 0.041 32.26 29.80 336 0.612
EO2: Chance of severe reaction 29.45 34.71 238 0.343 26.53 32.07 298 0.261
EO3: Chance of dying 29.04 36.33 218 0.186 24.85 32.73 270 0.108
EO4: Chance of not acting effectively 30.24 31.54 275 0.814 27.32 31.76 312 0.366
IM1: Number of foods to avoid 27.94 40.75 165 0.019 20.41 34.49 194 0.004
IM2: Effect on social life 27.38 43.00 138 0.004 18.71 35.16 165 0.001

Table S7 Spearman’s correlation of the values of FAQLQ-TF and its domains with the number of foods to avoid (P ˂ 0.001 in all cases).

Whole FAQLQ-TF Allergen avoidance Risk of accidental exposure Emotional impact Dietary restriction
Number of foods to avoid 0.674 0.647 0.607 0.555 0.614