Testing four cognition bolt-on items to the EQ-5D in a general Chinese population.

This study aimed to evaluate the psychometric properties of four candidate cognition bolt-on items and their combinations to the EQ-5D-5L. Four cognition items (concentration, memory, calculation, and learning) were developed as separate questionnaire items, and were administered with the standard EQ-5D-5L to 640 individuals in a general population survey in China. From the 4 items, 11 compound items were constructed, and the 'worse level counts' rule was used to calculate a compound item score. Psychometric performance of the cognition bolt-ons was assessed in terms of informativity, convergent validity, explanatory power, and discriminatory power. The tested four cognition bolt-on items improved the informativity, convergent validity, explanatory power, and discriminatory power of EQ-5D-5L, with calculation and learning yielding better psychometric performance. The compound bolt-on items that coverd a range of cognitive functions demonstrated superior psychometric performance compared to single-aspect bolt-on items, with those items covering calculation and learning resulting in better psychometric performance. This study confirmed the validity of the tested cognition bolt-ons in a general Chinese population. It supported the use of a compound bolt-on item covering a range of cognitive functions such as the ability to calculate and learn.

Liao M ，Wu H ，Yang Z ，Huang Y ，Janssen MF ，Bonsel G ，Luo N ... -  《-》

The added value of the cognition, dining, gastrointestinal problems, sleep and tiredness bolt-on dimensions to the EQ-5D-5L in patients with coeliac disease.

Multiple studies suggest that the EQ-5D may overestimate health-related quality of life (HRQoL) in patients with coeliac disease (CD). We aimed to develop and psychometrically test potentially relevant bolt-on dimensions to improve the measurement performance of the EQ-5D-5L in CD patients. The development and selection of bolt-ons were informed by a literature review on HRQoL in CD, expert and patient input. A cross-sectional online survey was conducted amongst 312 adult CD patients. Respondents completed the EQ-5D-5L, two condition-specific bolt-ons newly-developed for the present study [dining (DI) and gastrointestinal problems (GI)] and three existing bolt-ons [cognition (CO), sleep (SL) and tiredness (TI)]. The following psychometric properties were tested: ceiling, informativity, convergent and known-group validity, and dimensionality (confirmatory factor analysis). Adding the TI, SL, GI, DI and CO individual bolt-ons reduced the ceiling of the EQ-5D-5L (39%) to 17%, 23%, 24%, 26% and 37%, respectively. GI excelled with strong convergent validity with the Gastrointestinal Symptom Rating Scale total score (rs=0.71) and improved the discriminatory power for all known-groups. GI was the only bolt-on loading on a different factor from the five core dimensions, whereas the other four bolt-ons loaded onto the same 'psychosocial health' factor as the EQ-5D-5L anxiety/depression dimension. The DI, GI, SL and TI bolt-ons, especially the GI, enhance the validity of EQ-5D-5L in patients with CD, suggesting their value in capturing important HRQoL aspects potentially missed by the five core dimensions. These bolt-ons can be used in sensitivity analyses supporting health technology assessments and subsequent resource allocation decisions.

Angyal MM ，Janssen MF ，Lakatos PL ，Brodszky V ，Rencz F ... -  《-》

Testing the Psychometric Properties of 9 Bolt-Ons for the EQ-5D-5L in a General Population Sample.

We aimed to assess the psychometric performance and added value of 9 existing bolt-ons (breathing problems, cognition, hearing, self-confidence, skin irritation, sleep, social relationships, tiredness, and vision) for the EQ-5D-5L in a general population sample. The EQ-5D-5L, 9 bolt-ons, SF-6Dv1, Patient-Reported Outcomes Measurement Information System (PROMIS)-29+2, PROMIS Global Health, and Satisfaction with Life Scale were completed in an online cross-sectional survey among a general adult population sample in Hungary (n = 1587). The following psychometric properties were tested for the EQ-5D-5L + bolt-on(s): ceiling, divergent and convergent validity, structural validity, known-group validity, and explanatory power. Adding sleep (30%), tiredness (24%), or vision (21%) substantially reduced the ceiling of the EQ-5D-5L (41%). Cognition, sleep, social relationships, and tiredness correlated with corresponding PROMIS and SF-6D items (rs = ǀ0.32ǀ - ǀ0.73ǀ). All bolt-ons, except cognition and self-confidence, loaded on a different factor from the EQ-5D-5L dimensions. Breathing, hearing, skin irritation, and vision significantly improved known-group validity in relevant health condition groups. The sleep bolt-on improved known-group validity in 9 of 13 chronic health conditions. Tiredness had the largest impact on explaining EQ VAS score variance in 8 of 13 conditions. Hearing and vision improved the ability of the EQ-5D-5L to capture declining health with age, whereas self-confidence and social relationships were valuable for mental health assessment. This study established the validity of multiple bolt-ons for the EQ-5D-5L and highlights the usefulness of including relevant bolt-ons in population-based and patient surveys. Our findings inform the further development of these bolt-ons and the bolt-on item selection for clinical studies.

Rencz F ，Janssen MF 《-》

Performance of the EQ-5D-5L With Skin Irritation and Self-Confidence Bolt-On Items in Patients With Urticaria.

This study aimed to validate the EQ-5D-5L with the addition of skin irritation and self-confidence bolt-on items in Chinese patients with urticaria. The skin irritation and self-confidence bolt-on items were translated into Simplified Chinese and cognitively debriefed. A cross-sectional survey was subsequently conducted among patients diagnosed with urticaria in Guangdong Province, China. The questionnaire included the EQ-5D-5L with the 2 bolt-on items, along with the Dermatology Life Quality Index (DLQI) and Skindex-16. The study examined the ceiling effects, informativity, and known-group validity of the 2 bolt-on items. Multiple regression analysis was conducted to determine the explanatory power of the EQ-5D-5L and bolt-on items in predicting the EQ VAS. A total of 475 patients completed the questionnaire and were included in the analysis. The inclusion of the 2 bolt-on items reduced the ceiling effect from 54.95% to 4.21%. The skin irritation item showed a greater correlation with DLQI item 1 and the symptoms dimension of the Skindex-16 (correlation coefficients: 0.39 and 0.31, respectively). The self-confidence item exhibited a moderate correlation with DLQI item 2 (r = 0.42) and the functioning dimension of the Skindex-16 (r = 0.33). Known-group validity analysis confirmed that the skin irritation item demonstrated satisfactory discriminatory power. Multiple regression analyses indicated that the inclusion of skin irritation enhanced the explanatory power for EQ VAS more effectively than self-confidence. The inclusion of 2 bolt-ons in the EQ-5D-5L enhanced its informativity, convergent validity, discriminatory power, known group validity, and explanatory power among Chinese patients with urticaria.

Feng J ，Yin Y ，Luo N ，Guo J ，Wang D ，Mao Z ，He Z ，Lu C ，Li S ，Yu J ... -  《-》

Testing the psychometric characteristics of EQ-5D-5L and respiratory bolt-ons using a sample of the Australian population.

The EQ-5D has been used to assess health related quality of life (HRQoL) in respiratory conditions. However, the core descriptive system may not be sensitive to all the HRQoL impacts of these conditions. To increase the sensitivity of the descriptive system, two respiratory specific bolt-ons, have been developed. Psychometric assessment of the bolt-ons in comparison to other validated instruments is required to facilitate their use. Therefore, the aim of this study is to test the psychometric characteristics of the EQ-5D-5L + R using a large dataset collected in Australia. A cross-sectional online survey was used to recruit adult respondents (≥ 18 years) representative of the Australian population. Descriptive and psychometric analyses were used to understand the performance of the EQ-5D-5L and bolt-ons in comparison to other validated instruments. The construct validity was estimated using correlations. Known-group validity was tested to determine the sensitivity of the instruments to differences across different severity groups. Overall 10,033 respondents (52% female) completed the survey, of which 300 had a respiratory condition. There were moderate to high correlation between bolt-ons with EQ-5D-5L and WHODAS. The EQ-5D-5L + bolt-ons slightly reduced the ceiling effect in comparison to the EQ-5D-5L. The effect size was larger for people with respiratory conditions than people who did not have a respiratory condition. The results show that adding the respiratory bolt-on to the EQ-5D-5L might slightly improve the instruments descriptive sensitivity. The choice of bolt-on may be driven by whether overall problems or limitations are being measured.

Bahrampour M ，Kochovska S ，Currow DC ，Viney R ，Mulhern B ... -  《-》