Background COVID-19 has spread rapidly throughout the world, causing thousands of illnesses and deaths. To fight this pandemic, almost all governments and health authorities have focused on prevention. In March or April, most countries' officials imposed home quarantine and lockdown measures nationwide. Purpose This study sought to assess health-related quality of life (HRQoL) and anxiety levels among people in Portugal under mandatory home quarantine due to the COVID-19 pandemic. The results were compared to the general Portuguese population's HRQoL before the COVID-19 outbreak. This research also aimed to understand the factors that can influence the respondents' HRQoL. Methods A sample of Portugal's population quarantined at home (n = 904) filled in an online survey comprising the Generalized Anxiety Disorder 7-item and the EQ-5D-5L and other questions about sociodemographic characteristics, feelings, duties and activities during the quarantine. The sample was weighted to mirror the general population's gender, age and education. Descriptive analyses and correlation coefficients were used to evaluation the respondents' anxiety and HRQoL. Generalised linear models were estimated to identify determinants of HRQoL during the COVID-19 quarantine. Results The results show that individuals quarantined at home reported higher anxiety and lower HRQoL levels and that people with more anxiety tended to have a lower HRQoL. Females and elderly individuals experienced the highest levels of anxiety and poorest HRQoL. In addition, HRQoL during the quarantine can be explained by various occupational and attitudinal variables, as well as sociodemographic variables. Conclusion Individuals' mental health should be taken into consideration during pandemics or other emergency situations. Anxiety and other factors can decrease people's HRQoL, in conjunction with the pandemic's social and economic consequences.

This research provides the Portuguese EQ-5D value set based on the preferences of the Portuguese general population as measured by the TTO. This value set is recommended for use in CUA conducted in Portugal.

This study provides Portuguese population health-related quality of life data measured by the EQ-5D that can be used as population norms. These norms can be used to inform Portuguese policy makers, health care professionals and researchers in issues related to health care policy and planning and quantification of treatment effects on health status.

BackgroundSome studies have reported a ceiling effect in EQ-5D-3L, especially in healthy and/or young individuals. Recently, two further levels have been included in its measurement model (EQ-5D-5L). The purposes of this study were (1) to assess the properties of the EQ-5D-5L in comparison with the standard EQ-5D-3L in a sample of young adults, (2) to foreground the importance of collecting qualitative data to confirm, validate or refine the EQ-5D questionnaire items and (3) to raise questions pertaining to the wording in these questionnaire items.MethodsThe data used came from a sample of respondents aged 30 or under (n = 624). They completed both versions of the EQ-5D, which were compared in terms of feasibility, level of inconsistency and ceiling effect. Agreement between the instruments was assessed using correlation coefficients and Bland-Altman plots. Known-groups validity of the EQ-5D-5L was also assessed using non-parametric tests. The discriminative properties were compared using receiver operating characteristic curves. Finally, four interviews were conducted for retrospective reports to elicit respondents’ understanding and perceptions of the format, instructions, items, and responses.ResultsQuantitative results show a ceiling effect reduction of 25.3 % and a high level agreement between both indices. Known-groups validity was confirmed for the EQ-5D-5L. Explorative interviews indicated ambiguity and low degree of certainty in regards to conceptualizing differences between levels moderate-slight across three dimensions.ConclusionsThe EQ-5D-5L performed better than the EQ-5D-3L. However, the explorative interviews demonstrated several limitations in the EQ-5D questionnaire wording and high context-dependent answers point to lack of illnesses’ experience amongst young adults.