PurposeQuality of life (QOL) is an important concept in the field of health and medicine. QOL is a complex concept that is interpreted and defined differently within and between disciplines, including the fields of health and medicine. The aims of this study were to systematically review the literature on QOL in medicine and health research and to describe the country of origin, target groups, instruments, design, and conceptual issues.MethodsA systematic review was conducted to identify research studies on QOL and health-related quality of life (HRQOL). The databases Scopus, which includes Embase and MEDLINE, CINAHL, and PsycINFO were searched for articles published during one random week in November 2016. The ten predefined criteria of Gill and Feinstein were used to evaluate the conceptual and methodological rigor.ResultsQOL research is international and involves a variety of target groups, research designs, and QOL measures. According to the criteria of Gill and Feinstein, the results show that only 13% provided a definition of QOL, 6% distinguished QOL from HRQOL. The most frequently fulfilled criteria were: (i) stating the domains of QOL to be measured; (ii) giving a reason for choosing the instruments used; and (iii) aggregating the results from multiple items.ConclusionQOL is an important endpoint in medical and health research, and QOL research involves a variety of patient groups and different research designs. Based on the current evaluation of the methodological and conceptual clarity of QOL research, we conclude that the majority QOL studies in health and medicine have conceptual and methodological challenges.Electronic supplementary materialThe online version of this article (doi:10.1007/s11136-019-02214-9) contains supplementary material, which is available to authorized users.

First, to describe adolescents' health information sources and knowledge, health literacy (HL), health protective measures, and health-related quality of life (HRQoL) during the initial phase of the Covid-19 pandemic in Norway. Second, to investigate the association between HL and the knowledge and behavior relevant for preventing spread of the virus. Third, to explore variables associated with HRQoL in a pandemic environment. Methods This cross-sectional study includes survey data from 2,205 Norwegian adolescents 16-19 years of age. The participants reported on their health information sources, HL, handwashing knowledge and behavior, number of social interactions, and HRQoL. Associations between study variables and specified outcomes were explored using multiple linear and logistic regression analyses. Results Television (TV) and family were indicated to be the main sources for pandemic-related health information. Handwashing, physical distancing, and limiting the number of social contacts were the most frequently reported measures. HL and handwashing knowledge and HL and handwashing behavior were significantly associated. For each unit increase on the HL scale, the participants were 5% more likely to socialize less with friends in comparison to normal. The mean HRQoL was very poor compared to European norms. Being quarantined or isolated and having confirmed or suspected Covid-19 were significantly negatively associated with HRQoL, but seeing less friends than normal was not associated. HL was significantly positively associated with HRQoL, albeit of minor clinical importance.

Pain is a common problem and influences the daily lives of children and adolescents. Many parents are unaware of the pain experienced by their children. There is a need for preventive programmes that also involve parents, school nurses, and teachers.

Knowledge about predictors of health-related quality of life is especially important for public health nurses. Health promotion and intervention programmes that aim to strengthen psychosocial well-being, especially those that strengthen body image, should be developed for both genders.

Background To enhance and better understand health-related quality of life (HRQOL) in adolescents, it is important to study factors associated with HRQOL. The present study aimed to assess possible associations between sociodemographic variables, self-efficacy, self-esteem, pain, sleep, loneliness, stress and HRQOL in 14 to 15-year-old adolescents. Methods A cross-sectional study was performed among 696 adolescents (14–15 years) in a school-based setting. Sociodemographic variables, self-efficacy, self-esteem, pain, sleep, loneliness and stress were analyzed. The variables were all assessed with well-validated instruments. HRQOL was analyzed using KIDSCREEN 27. Analyses included Chi-square, independent t-tests, Mann–Whitney U tests, linear regression analyses and hierarchical regression analyses. The results from linear regression models were expressed as standardized beta. Results The adolescents generally reported high levels of HRQOL. However, girls scored significantly worse on HRQOL, self-efficacy, self-esteem, pain, sleep, loneliness and stress compared to boys. Using hierarchical regression analyses we found that Self-efficacy (beta = 0.11–0.24), Self-esteem: (beta = 0.12–0.21), Loneliness: (beta = − 0.24 to − 0.45) and Stress: (beta = − 0.26 to − 0.34) revealed the strongest associations with the HRQOL dimensions. Sociodemographic-, pain- and sleep related covariates were all significantly associated with some of the KIDSCREEN subscales, however their effect on the outcome was smaller than for the psychosocial variables listed above. Being a girl, not living with both parents, not having both parents working, being absent from school more than 4 days, having pain and having lack of enough sleep were all independently negatively associated with HRQOL. Conclusions HRQOL is strongly associated with self-efficacy, self-esteem, loneliness and stress in 14 to 15-year-old adolescents. Our findings indicate that positive psychosocial factors such as self-efficacy and self-esteem might play a buffer role for negative psychosocial factors (e.g. stress) in adolescents. Further, our results show that girls score significantly worse on factors that are associated to HRQOL compared to boys. To improve HRQOL in school-based populations of adolescents, we suggest that future interventions should aim to strengthen self-efficacy and self-esteem. We recommend gender specific interventions.

The aim of this study was to investigate the effects of vitamin C and E supplementation on changes in muscle mass (lean mass and muscle thickness) and strength during 12 weeks of strength training in elderly men. Thirty-four elderly males (60-81 years) were randomized to either an antioxidant group (500 mg of vitamin C and 117.5 mg vitamin E before and after training) or a placebo group following the same strength training program (three sessions per week). Body composition was assessed with dual-energy X-ray absorptiometry and muscle thickness by ultrasound imaging. Muscle strength was measured as one-repetition maximum (1RM). Total lean mass increased by 3.9% (95% confidence intervals: 3.0, 5.2) and 1.4% (0, 5.4) in the placebo and antioxidant groups, respectively, revealing larger gains in the placebo group (P = 0.04). Similarly, the thickness of m. rectus femoris increased more in the placebo group [16.2% (12.8, 24.1)] than in the antioxidant group [10.9% (9.8, 13.5); P = 0.01]. Increases of lean mass in trunk and arms, and muscle thickness of elbow flexors, did not differ significantly between groups. With no group differences, 1RM improved in the range of 15-21% (P< 0.001). In conclusion, high-dosage vitamin C and E supplementation blunted certain muscular adaptations to strength training in elderly men.

Background: While research on school children's health has mainly focused on risk factors and illness, few studies have examined aspects of health promotion. Thus, this study focuses on health promotional factors including general self-efficacy (GSE) and health-related quality of life (HRQOL). GSE refers to a global confidence in coping ability across a wide range of demanding situations, and is related to health. The purpose of this study was to examine associations between GSE and HRQOL, and associations between HRQOL and socio-demographic characteristics. Knowledge of these associations in healthy school children is currently lacking.

Background The COVID-19 pandemic has caused significant disruptions in the implementation of programs across educational institutions. Nursing students, being both young adults and by practical training, part of the health care system, may be particularly vulnerable during the COVID-19 pandemic. The purpose of this study was to explore the associations between self-reported fear of COVID-19, general health, psychological distress and overall quality of life (QoL) in a sample of Norwegian baccalaureate nursing students compared to reference data. Methods The survey targeted baccalaureate nursing students from five universities in February 2021. An electronic questionnaire consisted of the Fear of COVID-19 Scale (FCV-19S), the Hopkins Symptom Checklist 5 (SCL-5), one general health and one overall QoL question. The respondents’ mean scores were compared to reference data. Hierarchical regression analyses were conducted, and effect sizes (Cohen’s d) were evaluated. Results In total, 2605 out of 6088 (43%) students responded. Their FCV-19S scores (mean 2.45, CI 2.42, 2.48) were significantly higher than those of the reference population (mean 1.8, P < 0.001). Nursing students scores showed significantly lower general health (mean 3.50 ± 0.93 SD, population mean = 3.57, Cohen’s d = 0.07), higher levels of psychological distress (mean 2.68 ± 1.03 SD, population mean = 2.12, Cohen’s d = 0.55) and lower overall QoL (mean 5.50 ± 2.16 SD, population mean = 8.00, Cohen’s d = 1.16) compared to pre-pandemic reference data. FCV-19S scores were significantly associated with levels of general health (Cohen’s d = 0.26), psychological distress (Cohen’s d = 0.76) and overall QoL (Cohen’s d = 0.18). Conclusions Baccalaureate nursing students reported worse outcomes during the Covid-19 pandemic on general health, psychological distress and overall QoL compared to the reference population. Level of fear of Covid-19, however, accounted for few of these differences. Other factors related to the pandemic may have reduced nursing students’ overall QoL.