This paper as a first Meta-analysis on this topic provides a great insight into two major health conditions that the world is facing now and open doors to monitor those who are infected with COVID-19 and diagnosed with onset diabetes closely as high risk patients, however, there are few points I found them to be edited and worked on in upcoming papers by the authors or others. My comments are listed below:

1) Major points: 1- The authors did not provide an abstract to the paper, this may lead to less read and judging the paper by its title. 2- The paper lacks sections headlines', for example: Introduction, Methods and Results. 3- they conducted a sub-group analysis by country, yet they reported it as N/A in checklist.

2) Minor points: 1- I would like to suggest that the authors in future papers to provide the numbers of papers retrieved from each database, this would give more validation to the paper. 2- future papers should focus on diabetes type and include a follow up analysis if possible.