Quality Of Life In Short Stature Youth Research Articles

Growth hormone treatment in children with short stature: impact of the diagnosis on parents.

This prospective multicenter study aimed (1) to examine changes in parent-reported health-related quality of life (HRQOL) of children with short stature and the effects of the children's condition on parents themselves within the first year of human growth hormone (hGH) treatment and (2) to predict effects on parents based on main and interaction effects of children's HRQOL and increase in height. A total of 110 parents of children aged 4-18 years, diagnosed with idiopathic growth hormone deficiency, small for gestational age, or idiopathic short stature, were recruited from 11 participating German pediatric endocrinologists and asked to fill out the short stature-specific Quality of Life in Short Stature Youth (QoLISSY) Questionnaire before hGH treatment was initiated and one year later. Negative effects of the children's short stature on the parents decrease over time, independent of diagnosis and treatment status. Furthermore, treatment status and height increase moderated the links between children's improved HRQOL as perceived by their parents and decreased caregiving burden. Based on the children's improved HRQOL and the parent's decrease in caregiving burden, patient-reported outcomes that consider parental and child's perspectives should be considered when deciding on hGH treatment for children.

Health-related quality of life in pre-pubertal children with pediatric growth hormone deficiency: 12-month results from a phase 3 clinical trial of once-weekly somatrogon versus once-daily somatropin

Objective Treatment of pediatric growth hormone deficiency (pGHD) with daily injection of recombinant human growth hormone (somatropin) aims to increase height velocity and improve health-related quality of life (HRQoL). The Quality of Life in Short Stature Youth (QoLISSY) questionnaire was administered in a phase 3 clinical trial that evaluated efficacy and safety of once-weekly somatrogon versus once-daily somatropin in children with pGHD (ClinicalTrials.gov no NCT02968004). Methods Treatment-naïve prepubertal children with pGHD received once-weekly somatrogon or once-daily somatropin for 12 months. The QoLISSY core module (physical/social/emotional subscales) was administered at baseline and 12 months after treatment initiation. QoLISSY-Parent was completed by parents/caregivers of children <7 years old and some parents/caregivers of children ≥7 years old; children ≥7 years old self-completed QoLISSY-Child. Results Baseline characteristics were similar between treatment groups (N = 117). Among children <7 years old, QoLISSY-Parent total and subscale scores showed similarly improved HRQoL at 12 months relative to baseline in both treatment groups. Self-reported QoLISSY-Child total and subscale scores in children ≥7 years old indicated HRQoL improvements at 12 months that were numerically better with somatrogon than somatropin (similar results with QoLISSY-Parent in this age group). At both time points, children reported better HRQoL than perceived by their parents/caregivers. Conclusion Treatment for 12 months with once-weekly somatrogon or once-daily somatropin resulted in comparable improvements in HRQoL among children with pGHD. Lower HRQoL perceived by parents/caregivers possibly reflect children’s tendency to emphasize adaptation. These results suggest that evaluation of HRQoL could help support treatment decisions in children with pGHD treated with growth hormone.

Lifetime Impact Study for Achondroplasia (LISA): Findings from an observational and multinational study focused on health-related quality of life in individuals with achondroplasia in Latin America

PurposeThe multisystem clinical manifestations and complications of achondroplasia, the most common form of disproportionate short stature, can cause functional impairment and psychosocial burden. The Lifetime Impact Study for Achondroplasia (LISA), aimed to assess health-related quality of life and medical resource utilization among Latin America patients with achondroplasia. MethodsData were collected from individuals aged 3 years and above in Argentina, Brazil, and Colombia between 2018 and 2021. A total of 172 patients participated in the study. ResultsChildren with achondroplasia reported lower scores compared with average stature children in Quality of Life in Short Stature Youth (QoLISSY) and Pediatric Quality of Life Inventory (PedsQL) questionnaires, with the greatest impact on physical and social domains. Among adolescents, a significant percentage reported pain, 10.3% experienced pain in 3 or more sites. Adults scored lower than the reference population in the EQ-5D-5L Visual Analog Score, and a considerable portion reported moderate to severe anxiety/depression, pain or discomfort, and mobility problems. The Nottingham Health Profile (NHP) revealed poor health status in terms of energy, pain, and mobility. Medical events, particularly musculoskeletal and connective tissue disorders were reported, resulting in high medical resource utilization. ConclusionOverall, the Lifetime Impact Study for Achondroplasia study provides extensive data on health-related quality of life, psychosocial impact, and health care resource utilization among individuals with achondroplasia in Latin America. The findings confirm a significant burden of illness across multiple domains for these individuals.

FRI599 Quality Of Life In Girls With Turner Syndrome Using The Quality Of Life In Short Stature Youth Questionnaire (QoLISSY) - A Cross-sectional Study

Abstract Disclosure: N. Vijayakanthi: None. D.J. Marcus: None. S.P. Fritz: None. Y. Xiang: None. D.O. Fadoju: None. Background: Short Stature is a common finding in girls with Turner syndrome (TS). Its impact on Quality of life (QoL) in adolescents/adults with TS have been studied using generic QoL questionnaires. Short stature specific QoL questionnaires have not been used to study the impact of short stature and GH therapy in TS in previous studies. Methods: In this cross-sectional study, we aimed to evaluate QoL and the association between GH therapy and height on QoL of adolescents using the short stature specific questionnaire -Quality of Life in Short Stature Youth (QoLISSY). QoLISSY was designed specifically to assess QoL in short stature children with scales for both parents and children which assesses 3 core QOL dimensions: physical, social, emotional and 3 predictors of quality of life: Coping, Beliefs and Treatment (GH therapy). It has not been previously used in TS. Results: Of the 41 eligible patients, 37 patients were enrolled in the study. The mean age of our cohort was 16.3 ±1.3 years and the average final adult height was 145.03 ± 7.3 cm. About 70% of the patients received GH therapy and 80% received estrogen therapy. Compared to the reference short stature mean values, our TS cohort had comparable scores in all QoL subscales and total scores in both parent and patient reports apart from the parental report treatment subscale which was significantly lower than their respective reference short stature means [Mean ± SD: 47.43±27.13 vs 58.82±16.75; p=0.03]. Girls with height &amp;gt;-3SD had significantly lower score in the coping subscale, compared to the &amp;lt;-2SD height group [Mean ± SD: 42.14 ± 19.04 vs 62.25 ± 16.60; p= 0.024; multivariate analysis: p=0.012. In the parent report, the social subscale was significantly lower in the &amp;gt; -3SD height group compared to the &amp;lt;-2SD height group [Mean ± SD: 57.59 ± 22.25 vs 80.94 ± 11.26; p=0.022; multivariate analysis: p=0.024]. There was no statistically significant difference in the QOL between the GH vs no GH groups. Conclusion: We conclude that the QoL in girls with TS was comparable to the reference short stature population. GH therapy did not improve the QoL in girls with TS in our cohort. Height does not appear correlate with the overall QoL in girls with TS though they have some coping and social difficulties. We recommend psychological counseling and support for girls with TS especially to address their coping and social difficulties. Presentation: Friday, June 16, 2023

Quality of life in children and adolescents with growth hormone deficiency and their caregivers: an Italian survey

PurposeThe aim of this study was to produce evidence on quality of life (QoL) among Italian growth hormone deficiency (GHD) children and adolescents treated with growth hormone (GH) and their parents.MethodsA survey was conducted among Italian children and adolescents aged 4–18 with a confirmed diagnosis of GHD and treated with GH therapy and their parents. The European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L) and the Quality of Life in Short Stature Youth (QoLISSY) questionnaires were administered between May and October 2021 through the Computer-Assisted Personal Interview (CAPI) method. Results were compared with national and international reference values.ResultsThe survey included 142 GHD children/adolescents and their parents. The mean EQ-5D-3L score was 0.95 [standard deviation (SD) 0.09], while the mean visual analogue scale (VAS) score was 86.2 (SD 14.2); the scores are similar to those of a reference Italian population aged 18–24 of healthy subjects. As for the QoLISSY child-version, compared to the international reference values for GHD/ idiopathic short stature (ISS) patients, we found a significantly higher score for the physical domain, and lower scores for coping and treatment; compared to the specific reference values for GHD patients, our mean scores were significantly lower for all domains except the physical one. As for the parents, we found a significantly higher score for the physical domain, and a lower score for treatment; compared to reference values GHD-specific, we found lower score in the social, emotional, treatment, parental effects, and total score domains.ConclusionsOur results suggest that the generic health-related quality of life (HRQoL) in treated GHD patients is high, comparable to that of healthy people. The QoL elicited by a disease specific questionnaire is also good, and comparable with that of international reference values of GHD/ISS patients.

Caregiving burden and special needs of parents in the care of their short-statured children - a qualitative approach.

To explore caregiving burden, health-related quality of life (HRQOL), stress, and individual resources of parents in the care of children with isolated growth hormone deficiency (IGHD) or idiopathic short stature (ISS). Focused interview analysis of previously, within the Quality of Life in Short Stature Youth (QoLISSY) project, conducted structured focus group discussions (n=7) with parents (n=33) of children with IGHD/ISS aged 4 to 18 years were performed. 26 out of the 33 parents reported mental stress due to their child's growth disorder. Social pressure and stigmatization were also mentioned as being demanding. Some parents reported having trouble with human growth hormone (hGH) treatment. Several parents wished for parent support groups with other like-minded parents of short-statured children. For physicians, it is essential to understand the parents' caregiving burden, stress, and individual resources in caring for IGHD/ISS children. If an impaired HRQOL is detected, psychological intervention for these parents may be scheduled, and coping mechanisms may be discussed. Furthermore, it seems essential for parents to be educated by their healthcare provider about the possible side effects of hGH treatment or to know where to find evidence-based information about it.

Comparison of Quality of Life Responses From Caregiver and Children Aged ≥7 Years Using the Quality of Life in Short Stature Youth (QoLISSY) Questionnaire, Following 12 Months of Growth Hormone Treatment With Either a Weekly Somatrogon or a Daily Genotropin Injection Schedule

Objective: Paediatric growth hormone deficiency (pGHD) affects 1/4,000 children. Treatment with daily sub-cutaneous injections of recombinant human growth hormone (r-hGH) increase height velocity and quality of life (QoL). A recent randomised controlled clinical trial (NCT02968004) evaluated the efficacy/safety of weekly Somatrogon (hGH-CTP) and daily Genotropin in pGHD. QoL (an exploratory endpoint) was evaluated using the validated Quality of Life in Short Stature Youth (QoLISSY) questionnaire, which includes three subscales (physical, social, emotional) and total score. Methods: The QoLISSY core module was administered to patients (aged 3-11 years [girls], 3-12 years [boys]) and parents in US, UK, Australia, New Zealand, Belarus, Russia, Ukraine and Spain, at Baseline (BL) and 12 months after treatment start. The QoLISSY-CHILD was completed by children aged ≥7 years; QoLISSY-PARENT was completed by the Caregiver for children <7 years, and for some children aged ≥7 years. We report here only the QoLISSY results for children aged ≥7 years (reported from either child or parent). Results: For Total QoLISSY-PARENT, for children aged ≥7 years in the Somatrogon group (N=26), mean scores are 53.65 (BL) and 65.52 (month 12) with mean change of 13.01 (95% Confidence Interval [CI]: 3.99, 22.02). In the Genotropin group (N=28), mean scores are 55.89 (BL) and 63.66 (month 12) with mean change of 6.60 (CI:-0.21, 13.40). For Total QoLISSY-CHILD in the Somatrogon group (N=35), mean scores are 61.48 (BL) and 74.69 (month 12) with mean change of 13.00 (CI: 5.81, 20.19). In the Genotropin group (N=35), these scores are 60.96 (BL) and 69.03 (Month 12) with mean change of 7.84 (CI: 2.71, 12.97). Scores of >70 indicate a good QoL. Conclusions: QoL in children aged ≥7 years improved, following 12 months of either treatment, whether this was reported by caregiver or child. However, these data show that the baseline scores and 12 month scores from the QoLISSY-PARENT in both treatment groups were numerically lower than those reported by the child. This is consistent with the literature¹, in which the caregivers generally report lower QoL scores on behalf of the child.¹Explaining parent-child (dis)agreement in generic and short stature-specific health-related quality of life reports: do family and social relationships matter? Quitmann et al Health and Quality of Life Outcomes 2016 vol 14, Article 150

PDB4 Evaluation of Quality of Life in PRE-Pubertal Children Using the Quality of Life in Short Stature Youth (QOLISSY) Questionnaire, Following 12 Months of Growth Hormone Treatment with Either a Weekly Somatrogon or a Daily Genotropin Injection Schedule

Paediatric growth hormone deficiency (pGHD) affects 1/4,000 children. Treatment with daily sub-cutaneous injections of recombinant human growth hormone (r-hGH) increase height velocity and quality of life (QoL). However, adherence to daily r-hGH varies; one study reported 66% of children were non-compliant (>1 injection/ week missed)1. A recent randomised controlled clinical trial (NCT02968004) evaluated the efficacy/safety of weekly Somatrogon (hGH-CTP) and daily Genotropin in pGHD. QoL (an exploratory endpoint) was evaluated using the validated Quality of Life in Short Stature Youth (QoLISSY) questionnaire, which includes three subscales (physical, social, emotional) and total score. The QoLISSY core module was administered to patients (aged 3-11 years [girls], 3-12 years [boys]) and parents in eight countries, at Baseline (BL) and 12 months after treatment start. The QoLISSY-CHILD was completed by children aged ≥7 years; QoLISSY-PARENT was completed by the Caregiver for children < 7 years. For Total QoLISSY-PARENT, in the Somatrogon group (N=19), mean scores are 61.82 (BL) and 69.49 (month 12) with mean change of 8.48 (95% Confidence Interval [CI]: 1.06, 15.89). In the Genotropin group (N=28), mean scores are 54.58 (BL) and 63.80 (month 12) with mean change of 8.51 (CI: 2.27, 14.74). For Total QoLISSY-CHILD (> 70% male), in the Somatrogon group (N=35), mean scores are 61.48 (BL) and 74.69 (month 12) with mean change of 13.00 (CI: 5.81, 20.19). In the Genotropin group (N=35), these scores are 60.96 (BL) and 69.03 (Month 12) with mean change of 7.84 (CI: 2.71, 12.97). All three sub-scales (both QoLISSY versions) showed similar trends in improvement over 12 months. Scores of >70 indicate a good QoL. QoLISSY-CHILD and QoLISSY-PARENT demonstrated comparable QoL improvements for children with pGHD by end of Month 12 in weekly Somatrogon and daily Genotropin treated groups. 1Cutfield et al PLoS ONE 6.1 (2011): 1-3.

Validation of the Greek version of the Quality of Life in Short Stature Youth (QoLISSY) questionnaire.

Background The Quality of Life in Short Stature Youth (QoLISSY) questionnaire is a condition-specific instrument for measuring the health-related quality of life (HRQoL) in short statured children/adolescents from patients' and parents' perspectives. The aim of this study was to investigate the psychometric properties of the Greek version of the QoLISSY questionnaire. Methods The original European QoLISSY scales were translated into Greek following the guidelines for linguistic validation and applied to 184 dyads of children 8-18 years old and their parents, as well as to 14 parents of children 4-7 years old in Greece. The field testing responses to the Greek version of QoLISSY were analyzed. Results The qualitative analysis of the Greek data provided results consistent with the European sample. The subsequent field test showed acceptable internal consistency (Cronbach α between 0.67-0.93) and high test-retest reliability (intraclass correlation coefficients [ICC] ≥0.70). Correlations with the generic KIDSCREEN questionnaire indicated good convergent validity. Confirmatory factor analysis (CFA) also yielded acceptable results. Higher HRQoL for taller children suggests that QoLISSY was able to detect significant height-related differences. Conclusions The Greek version of the QoLISSY questionnaire is psychometrically sound and its use is recommended in further clinical research to ascertain the impact of short stature (SS) and treatments in Greek children/adolescents and families.

Improved General and Height-Specific Quality of Life in Children With Short Stature After 1 Year on Growth Hormone.

Short stature in children and adolescents may lead to social and emotional stress, with negative effects on quality of life (QoL). GH treatment may improve QoL through height normalization. Our objective here was to evaluate general and height-specific QoL after 1 year of GH treatment. Prospective, single-center, observational cohort study. Children ≥ 4 years of age starting GH at our center from 2012 to 2015 to treat short stature were studied. Patients with serious diseases, syndromic short stature, or developmental delay were excluded. At treatment initiation and 1 year later, patients and their parents completed the general PedsQL 4.0 and height-specific Quality of Life in Short Stature Youth (QoLiSSY) questionnaires. Correlations between self-report and parent-report scores and between height gain and QoL improvements were assessed based on Pearson correlation coefficients. Seventy-four children (42 boys, 32 girls), median age (± SD), 10.2 ± 3.0 years (range, 4.1 to 16.6 years), were included. The self-report PedsQL indicated significant improvements in emotional (P = 0.02) and social (P = 0.03) QoL. As assessed by the QoLiSSY, children reported improvement of social QoL (+0.2 SD; P = 0.04), and parents reported improvement of children's physical (+0.1 SD; P < 0.0001), emotional (+0.3 SD; P < 0.0001), and social (+0.3 SD; P < 0.0001) QoL. Height SD score (SDS) gains showed moderate positive correlations with QoLISSY self-report score gains (R = 0.53, R2 = 0.28; P < 0.001) and QoLISSY parent-report gains (R = 0.60, R2 = 0.41; P < 0.00001). After 1 year of GH treatment, children had significant gains in emotional and social QoL, as assessed by a general self-report questionnaire and height-specific parent-report questionnaire.

The psychometric evaluation of the quality of life in short stature youth (QoLISSY) instrument for German children born small for gestational age.

This study aimed to validate the disease-specific "quality of life in short stature youth (QoLISSY)-instrument" that assessesQuery the health-related quality of life (HrQoL) in German children and adolescents diagnosed as small for gestational age (SGA) in a patient and parent report. The psychometric performance of the German version of the QoLISSY questionnaire was examined in terms of reliability and validity in 65 SGA families (17 child reports/64 parent reports) and compared to the psychometric performance of the original European QoLISSY dataset of over 200 children with growth hormone deficiency and idiopathic short stature (ISS). The analysis yielded psychometrically favorable results with excellent reliability and acceptable discriminant validity. The instrument's operating characteristics were comparable to the results of the original European QoLISSY data. In the parent- as well as child report, children with SGA had lower HrQoL scores than children with ISS. Convergent validity was demonstrated by significant correlations between the QoLISSY scales and the generic KIDSCREEN-10 Index. Psychometric testing suggests that QoLISSY is a promising instrument to assess the HrQoL of young German people with SGA. Both versions (parent- and child report) appear to detect differences between SGA and other conditions (e.g. ISS). QoLISSY can be used in clinical studies, health service research, as well as in practice in children with SGA and their parents. For a cross-cultural application of the instrument in SGA, the tool needs be validated in sufficiently large SGA samples within respective countries.

Validation of the Italian Quality of Life in Short Stature Youth (QoLISSY) questionnaire

The Quality of Life in Short Stature Youth (QoLISSY) questionnaire is a disease-specific instrument developed to assess health-related quality of life (HrQoL) in children with short stature. While the original instrument was simultaneously developed in five European countries, this study describes the results of the Italian QoLISSY translation, cultural adaptation, and validation. Focus group discussions and a cognitive debriefing process with children (N = 12) diagnosed with growth hormone deficiency or idiopathic short stature and one parent each, as well as parents of younger children (N = 20) were conducted to examine the linguistic and content validity of the Italian version. Psychometric testing was performed using data from the subsequent field- and re-test (N = 32). The results of the qualitative testing of the Italian sample revealed comparability of content to data of the original five European countries. The following field- and re-test results were psychometrically satisfactory including good item and scale operating characteristics, sufficient evidence of reliability, and acceptable evidence of construct validity. In conclusion, the Italian QoLISSY HrQoL-dimensions are comparable to other European countries. The psychometric quality of the Italian QoLISSY version is satisfactory and the instrument is ready for use in Italian patients and their parents.

A Brief Version of the Quality of Life in Short Stature Youth Questionnaire - the QoLISSY-Brief

The Quality of Life in Short Stature Youth (QoLISSY) questionnaire measures health-related quality of life (HrQoL) in short statured children (8–18 years) from patient and parent perspectives. To minimize respondent burden when assessing HrQoL in clinical practice, a brief version of the currently available 22-item QoLISSY is needed. The dataset of the European QoLISSY study (N = 268) was divided into two subdatasets at random, one to identify the items of the brief questionnaire and the other to test the operating characteristics (reliability and validity). Concept-based construction involved the selection of three items per Quality of Life (QoL)-dimension (physical, social, emotional) according to the highest corrected item-scale correlation. Psychometric properties were inspected in terms of reliability and validity supplemented by testing item fit statistics to examine item response theory (IRT) compliance. Cronbach’s alpha for the 9-item version was 0.89 for the patient- and the parent report. Pearson’s correlations with the generic KIDSCREEN questionnaire were low to moderate (children: r = 0.17–0.58; parents: r = 0.12–0.56). Shorter children reported significantly poorer QoL (mean difference 15.39 points; p < 0.001) than taller children, indicating known-groups validity. Results from IRT analysis showed an acceptable fit to Masters’ Partial Credit Model. The 9-item QoLISSY brief version has satisfactory operating characteristics and is an efficient alternative for use in research and practice.

Psychometric performance of the Quality of Life in Short Stature Youth (QoLISSY) questionnaire in the Netherlands.

The European Quality of Life in Short Stature Youth (QoLISSY) questionnaire is a disease-specific instrument assessing quality of life (QoL) in children with short stature from the child and parent perspectives. In order to use the QoLISSY in Dutch samples, a translation process and psychometric testing is needed. Children diagnosed with short stature (8 to 18 years) and their parents were recruited from a Dutch growth clinic. Reliability was assessed using Cronbach's α and intraclass correlation coefficients (ICCs). Pearsons' correlations with the generic KIDSCREEN and a confirmatory factor analysis (CFA) were performed to test validity. Scales showed good internal consistency with α ranging from 0.80 to 0.94 (child report) and from 0.85 to 0.95 (parent report). Test-retest reliability (ICC) ranged from 0.15 to 0.91 (child report) and from 0.14 to 0.83 (parent report). Correlations with the KIDSCREEN in the mean range indicated criterion validity. The models' goodness of fit was confirmed by CFA results in the Dutch and in comparison with the European sample. The Dutch QoLISSY is a psychometrically reliable and valid short stature-specific QoL measure. It is now available for use in clinical research and practice to evaluate well-being and possible effects of growth hormone treatment and psychological interventions in the Netherlands.

Quality of life in children, adolescents, and young adults with achondroplasia

Compared to research on short-statured adults, quality of life (QoL) of children has been rarely studied. One reason for this might be the lack of appropriate disease-specific questionnaires. The aim of this study was to analyse the quality of life in a sample of short-statured children with achondroplasia, using generic and disease-specific instruments. In addition, a comparison of patient and population norms is presented. The sample included children (8-28years) with achondroplasia and parents of participating children (8-17years). Quality of life was analyzed with the KIDSCREEN, the DISABKIDS and the disease-specific Quality of Life in Short Stature Youth (QoLISSY) questionnaire. In addition group differences according to clinical and sociodemographic data were analyzed within the sample and compared to available KIDSCREEN representative population data. The physical QoL was rated poorly in this sample of short-statured patients, while the emotional QoL was rated more favorably. Compared to the KIDSCREEN population norm, parents of children with achondroplasia rate the QoL lower. The QoLISSY questionnaire is a reliable tool to assess the subjective wellbeing of patients with skeletal dysplasia. The instrument can now be used clinically as a screening for patient wellbeing, as an outcome criterion in clinical research and as a psychosocial indicator in orthopedic cohort studies.

Cross-Cultural Equivalence of the Patient- and Parent-Reported Quality of Life in Short Stature Youth (QoLISSY) Questionnaire

Background: Testing cross-cultural equivalence of patient-reported outcomes requires sufficiently large samples per country, which is difficult to achieve in rare endocrine paediatric conditions. We describe a novel approach to cross-cultural testing of the Quality of Life in Short Stature Youth (QoLISSY) questionnaire in five countries by sequentially taking one country out (TOCO) from the total sample and iteratively comparing the resulting psychometric performance. Methods: Development of the QoLISSY proceeded from focus group discussions through pilot testing to field testing in 268 short-statured patients and their parents. To explore cross-cultural equivalence, the iterative TOCO technique was used to examine and compare the validity, reliability, and convergence of patient and parent responses on QoLISSY in the field test dataset, and to predict QoLISSY scores from clinical, socio-demographic and psychosocial variables. Results: Validity and reliability indicators were satisfactory for each sample after iteratively omitting one country. Comparisons with the total sample revealed cross-cultural equivalence in internal consistency and construct validity for patients and parents, high inter-rater agreement and a substantial proportion of QoLISSY variance explained by predictors. Conclusion: The TOCO technique is a powerful method to overcome problems of country-specific testing of patient-reported outcome instruments. It provides an empirical support to QoLISSY's cross-cultural equivalence and is recommended for future research.

Validation of the Flemish version of the Quality of Life in Short Stature Youth (QoLISSY) questionnaire

Objectives:The Quality of Life in Short Stature Youth (QoLISSY) questionnaire was recently developed in five European countries to assess health-related quality of life in children and adolescents with idiopathic short stature or growth hormone deficiency from child and parent perspectives. In addition to the existing French version, a Flemish version is needed for use of QoLISSY in the Flemish speaking part of Belgium.Methods:Children (8–18 years) and their parents recruited from two Belgian paediatric endocrinology clinics completed the QoLISSY in a cross-sectional study. Cronbach’s Alpha and test–retest reliability was assessed. Validity was examined by correlation with the generic KIDSCREEN questionnaire as well as by group comparisons according to diagnostic and treatment status.Results:The QoLISSY scales had an acceptable internal consistency with Cronbach’s Alpha ranging from 0·80 to 0·94 (child version) and from 0·77 to 0·92 (parent version). Test–retest reliability correlation coefficients ranged from r = 0·75 to 0·89 in the child version and from r = 0·58 to 0·85 in the parent version. Moderate correlations with the generic KIDSCREEN questionnaire suggested construct validity. Differences between child groups according to child age, underlying diagnosis, and degree of height deficit were found. Correlations with the European QoLISSY were significant for all scales.Discussion:The Flemish QoLISSY instrument is a psychometrically sound, reliable, and valid short stature specific questionnaire measuring health-related quality of life. It is expected to be of great use in upcoming clinical research on growth disorders and growth hormone treatment in Belgium and Europe.