Background The COVID-19 outbreak is a global pandemic, during which the community preventive and protective behaviors play a crucial role in the containment and control of infection. This study was designed to contribute to the existing knowledge on how risk communication (RC) and risk perception (RP) affect protective and preventive behaviors (PPB) during the COVID-19 outbreak. Methods The required data were extracted from a national online survey of Iranian adults aged 15 and older during March 15–19, 2020 (n=3213). Data analysis was performed using structural equation modeling. Results The study findings reveal that RC has direct and indirect positive effects on PB. Furthermore, this study also provides new evidence indicating that RP mediates the relationship between RC and PB and there is a two-way relationship between RC and RP. These interactions may have impact on risk communication strategies which should be adopted during this pandemic. Conclusion The study findings have remarkable implications for informing future communications as well as interventions during this ongoing outbreak and subsequent national risk events.

Background Recent years have witnessed a strong tendency to apply economic evidence as a guide for making health resource allocation decisions, especially those related to reimbursement policies. One such measure is the use of the cost-effectiveness threshold as a benchmark. This study explored the threshold for use in the health system of Iran by determining society’s preferences. Methods A cross-sectional household survey based on the contingent valuation method was administered to a representative general population of 1002 in Tehran, Iran from April to June 2015. The survey was intended to estimate the respondents’ willingness-to-pay (WTP) preferences for one quality-adjusted life year (QALY) gained. The valuation scenarios featured 12 vignettes on mild to severe diseases that can change people’s quality of life. The mean of WTP for QALY was estimated using different health instruments, and the determinants of such willingness were analyzed using the Heckman selection model. Results WTP for QALY varied depending on the severity of a disease and the instrument used to determine health preferences. Mean low health state value were associated with high valuation. The best estimated WTP values ranged from US$1032 to US$2666 and 0.22–0.56 of Iran’s local gross domestic product (GDP) per capita in 2014. Except for educational level, significant variables differed across different disease scenarios. Generally, a high health state valuation for target diseases, high income, high educational level, and being married were associated with high WTP for QALY. Conclusion From the general public’s perspective, the monetary value of QALY for mild to severe diseases with no risk of death was less than one GDP per capita. Therefore, the obtained valuation range is recommended as reference only for the adoption of interventions designed to improve quality of life. Future studies should estimate the threshold of interventions for life-threatening diseases or formulate transparent policies in such contexts. Electronic supplementary material The online version of this article (10.1186/s12962-019-0172-9) contains supplementary material, which is available to authorized users.

[Purpose]Studies of L-carnitine in healthy athletic populations have yielded equivocal results. Further scientific-based knowledge is needed to clarify the ability of L-carnitine to improve exercise capacity and expedite the recovery process by reducing oxidative stress. This study aimed to examine the 9-week effects of L-carnitine supplementation on exercise performance, anaerobic capacity, and exercise-induced oxidative stress markers in resistance-trained males.[Methods]In a double-blind, randomized, and placebo-controlled treatment, 23 men (age, 25±2y; weight, 81.2±8.31 kg; body fat, 17.1±5.9%) ingested either a placebo (2 g/d, n=11) or L-carnitine (2 g/d, n=12) for 9 weeks in conjunction with resistance training. Primary outcome measurements were analyzed at baseline and at weeks 3, 6, and 9. Participants underwent a similar resistance training (4 d/w, upper/lower body split) for a 9-week period. Two-way ANOVA with repeated measures was used for statistical analysis.[Results]There were significant increases in bench press lifting volume at wk-6 (146 kg, 95% CI 21.1, 272) and wk-9 (245 kg, 95% CI 127, 362) with L-carnitine. A similar trend was observed for leg press. In the L-carnitine group, at wk-9, there were significant increases in mean power (63.4 W, 95% CI 32.0, 94.8) and peak power (239 W, 95% CI 86.6, 392), reduction in post-exercise blood lactate levels (-1.60 mmol/L, 95% CI -2.44, -0.75) and beneficial changes in total antioxidant capacity (0.18 mmol/L, 95% CI 0.07, 0.28).[Conclusion]L-carnitine supplementation enhances exercise performance while attenuating blood lactate and oxidative stress responses to resistance training.

Background: Severe coronavirus disease 2019 (COVID-19) may lead to the cytokine storm syndrome which may cause acute respiratory failure syndrome and death. Our aim was to investigate the therapeutic effects of infliximab, intravenous gammaglobulin (IVIg) or combination therapy in patients with severe COVID-19 disease admitted to the intensive care unit (ICU). Methods: In this observational research, we studied 104 intubated adult patients with severe COVID-19 infection (based on clinical symptoms, and radiographic or CT scan parameters) who were admitted to the ICU of a multispecialty hospital during March 2020 in Tehran, Iran. All cases received standard treatment regimens as local protocol (Oseltamivir + hydroxychloroquine + lopinavir/ritonavir or sofosbuvir or atazanavir ± ribavirin). The cases were grouped as controls (n = 43), infliximab (n = 27), IVIg (n = 23) and combination (n = 11). Results: There was no significant difference between controls and treatment groups in terms of underlying diseases or the number of underlying diseases. The mean age (SD) of cases was 72.42 (16.06) in the control group, 64.52 (12.965) in IVIg, 63.40 (17.57) in infliximab and 64.00 (11.679) in combination therapy; (P = 0.047, 0.031 and 0.11, respectively). Also, 37% in the infliximab group, 26.1% in IVIg, 45.5% in combination therapy, and 62.8% in the control group expired (all P < 0.05). Hazard ratios were 0.31 in IVIg (95% CI: 0.12-0.76, P = 0.01), 0.30 in infliximab (95% CI: 0.13-0.67, P = 0.004), 0.39 in combination therapy (95% CI: 0.12-1.09, P = 0.071). Conclusion: According to the findings of this study, it seems that infliximab and IVIg, alone or together, in patients with severe COVID-19 disease can be considered an effective treatment.