School of Tropical Medicine and Global Health,

Nagasaki University, Nagasaki 852-8523, Japan.


Nguyen Tien Huy, M.D., Ph.D

Associate Professor

Founder of Online Research Club, Head of Lab.

School of Tropical Medicine and Global Health, Nagasaki University,

1-12-4 Sakamoto, Nagasaki, 852-8523, Japan


Tel: +81-95-819-7558

Fax: +81-95-819-7846


Clinical and laboratory factors associated with coronavirus disease 2019 (Covid-19): a systematic review and meta-analysis

Summary: Covid-19 is one of the most widespread viruses globally during the 21st century, whose severity and ability to cause severe pneumonia and death vary.

We performed a comprehensive systematic review of all studies that met our standardized criteria and then extracted data on the age, symptoms, and different treatments of Covid-19 patients and the prognosis of this disease during follow-up. Cases in this study were divided according to severity and death status and meta-analyzed separately using raw mean and single proportion methods.

We included 171 complete studies including 62,909 confirmed cases of Covid-19, of which 148 studies were meta-analyzed. Symptoms clearly emerged in an escalating manner from mild-moderate symptoms, pneumonia, severe-critical to the group of non-survivors. Hypertension (Pooled proportion (PP): 0.48 [95% Confident interval (CI): 0.35-0.61]), diabetes (PP: 0.23 [95% CI: 0.16-0.33]) and smoking (PP: 0.12 [95%CI: 0.03-0.38]) were highest regarding pre-infection comorbidities in the non-survivor group. While acute respiratory distress syndrome (PP: 0.49 [95% CI: 0.29-0.78]), (PP: 0.63 [95%CI: 0.34-0.97]) remained one of the most common complications in the severe and death group respectively. Bilateral ground-glass opacification (PP: 0.68 [95% CI: 0.59-0.75]) was the most visible radiological image. The mortality rates estimated (PP: 0.11 [95% CI: 0.06-0.19]), (PP: 0.03 [95% CI: 0.01-0.05]), and (PP: 0.01 [95% CI: 0-0.3]) in severe-critical, pneumonia and mild-moderate groups respectively.

This study can serve as a high evidence guideline for different clinical presentations of Covid-19, graded from mild to severe, and for special forms like pneumonia and death groups.

Keywords: Covid-19, SARS-CoV-2, ARDS, symptomatology, pneumonia, death, critical, mild, radiology, laboratory

Download full-text & supplement materials here, Original article here

How to cite: Minh LHN, Abozaid AAA, Ha NX, Le LQ, Gadmil A, Tiwari R, Le TN, Dinh QK, AL-Manaseer B, Kien ND, Vuong NL, Zayan AH, Nhi LHH, Dila KAS, Varney J, Huy NT. Clinical aspect of novel Coronavirus (2019-nCoV): a systematic review and meta-analysis. Rev Med Virol. 2021;e2288. doi:10.1002/rmv.2288.

Reviews in Medical Virology (RMV); Short Title: Rev Med Virol; DOI: 10.1002/(ISSN)1099-1654; Electronic ISSN: 1099-1654; Print ISSN: 1052-9276; Article ID: RMV2288; Article type: review article; Article DOI: 10.1002/rmv.2288; Copyright: © 2021 John Wiley & Sons Ltd.

Lessons Learned from the Reemergent Coronavirus Disease 2019 (COVID-19) Cases in Areas of Long-reported No Community Transmission

Sep 2020 | Clinical Infectious Diseases

AUTHORS: Ibrahim Y, Raut A, Varney J, Sidhu A, Dong V, Huy NT

Keywords: COVID-19, outbreak, community transmission, containment measures, solutions

COVID-19: the current situation in Afghanistan

Jun 2020 | Lancet Glob Health

AUTHORS: Shah J, Karimzadeh S, Al-Ahdal TMA, Mousavi SH, Zahid SU, Huy NT.

No abstract available.

Frequent inappropriate use of unweighted summary statistics in systematic reviews of pathogen genotypes or genogroups

Mar 2020 | J Clin Epidemiol

AUTHOR: Tran L, Y MN, Thai Le Ba Nghia TLB, Hendam A, Vuong NL, Alzalal E, Ahmed M. Sayed AM, Hussain MM, Akash Sharma A, Tieu T, Peterson Gitonga Mathenge PG, Hirayama K, Alexander N, Huy NT.


Objectives: Our study aimed to systematically assess and report the methodological quality used in epidemiological systematic reviews (SRs) and meta-analysis (MA) of pathogen genotypes/genogroups.

Study design and setting: Nine electronic databases and manual search of reference lists were used to identify relevant studies. The method types were divided into three groups: 1) with weighted pooling analysis (which we call MA), (2) unweighted analysis of the study-level measures (which we call summary statistics), and (3) without any data pooling (which we call SR only). Characteristics were evaluated using Assessment of Multiple Systematic Reviews (AMSTAR), Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA), and Risk Of Bias In Systematic reviews (ROBIS) tools. The protocol was registered in PROSPERO with CRD42017078146.

Results: Among 36 included articles, 5 (14%) studies conducted SR only, 16 (44%) performed MA, and 15 (42%) used summary statistics. The univariable and multivariable linear regression of AMSTAR and PRISMA scores showed that MA had higher quality compared with those with summary statistics. The SR only and summary statistics groups had approximately equal scores among three scales of AMSTAR, PRISMA, and ROBIS. The methodological quality of epidemiological studies has improved from 1999 to 2017.

Conclusion: Despite the frequent use of unweighted summary statistics, MA remains the most suitable method for reaching rational conclusions in epidemiological studies of pathogen genotypes/genogroups.

Keywords: Genogroups; Genotypes; Meta-analysis; Methodological quality; Summary statistics; Systematic review.

Introduction of Novel Surgical Techniques: A Survey on Knowledge, Attitude, and Practice of Surgeons

Oct 2019 | Surg Innov

AUTHORS: Ahmed AM, Giang HTN, Sherief G, Hosni S, Altibi AM, Huynh S, Tang NA, Cuong T, Tuan LQA, Vuong NL, Mohamed A, Ghorab, Muhammad, Ngan T, Sameh E, Elmaraezy A, Minh LHN, Hirayama K, Huy NT.


Purpose: To investigate the knowledge, attitude, and practice of surgeons toward introducing novel surgical techniques in Egypt, Palestine, and Vietnam.

Summary Background Data: Despite the recent advances in modern surgical care and its role in advancing the quality and the length of lives, surgery in the developing world has stagnated or even regressed.

Methods: A survey was undertaken among the surgeons in 9 hospitals belonging to the 3 countries. Questions were categorized into knowledge, attitude, and practice questions. Meta-analyses were performed to estimate the event rate and compare between knowledge and practice, senior and junior surgeons.

Results: A total of 244 responses, with a response rate of 79.7%, were included in the analysis. Regarding knowledge and attitude, the results were satisfactory except that only 55.8% of surgeons appraised their level of education and 43.3% wanted to earn money from the novel procedure. There was a significant difference between knowledge and practice regarding getting informed consent from the patients (P = .024), discussing the novelty of the procedure (P < .001), discussing the alternative procedures (P < .001), discussing the surgeons' experience and level of skills (P < .001), discussing the risk of the new procedure (P < .001), and monitoring the outcomes after the new procedure (P < .001).

Conclusions: Most surgeons have sufficient knowledge and are motivated regarding adopting novel surgical techniques in order to provide the best care for the patients. However, there was a gap between knowledge and practice. Training programs and evidence-based guidelines regarding the introduction of novel surgical techniques are needed to overcome these challenges.

Keywords: business of surgery; evidence-based medicine; evidence-based surgery; surgical education.

Participants' understanding of informed consent in clinical trials over three decades: systematic review and meta-analysis

Mar 2015 | Bull World Health Organ.

AUTHORS: Tam NT, Huy NT (CA) Thoa LTB, Long NP, Trang NTH, Hirayama K, Karbwang J.


Objective: To estimate the proportion of participants in clinical trials who understand different components of informed consent.

Methods: Relevant studies were identified by a systematic review of PubMed, Scopus and Google Scholar and by manually reviewing reference lists for publications up to October 2013. A meta-analysis of study results was performed using a random-effects model to take account of heterogeneity.

Findings: The analysis included 103 studies evaluating 135 cohorts of participants. The pooled proportion of participants who understood components of informed consent was 75.8% for freedom to withdraw at any time, 74.7% for the nature of study, 74.7% for the voluntary nature of participation, 74.0% for potential benefits, 69.6% for the study's purpose, 67.0% for potential risks and side-effects, 66.2% for confidentiality, 64.1% for the availability of alternative treatment if withdrawn, 62.9% for knowing that treatments were being compared, 53.3% for placebo and 52.1% for randomization. Most participants, 62.4%, had no therapeutic misconceptions and 54.9% could name at least one risk. Subgroup and meta-regression analyses identified covariates, such as age, educational level, critical illness, the study phase and location, that significantly affected understanding and indicated that the proportion of participants who understood informed consent had not increased over 30 years.

Conclusion: The proportion of participants in clinical trials who understood different components of informed consent varied from 52.1% to 75.8%. Investigators could do more to help participants achieve a complete understanding.