1.1  Need for the study: As a government designated COVID centre, our institution is catering to a large population suffering from COVID 19. There is a need to study the clinical, biochemical spectrum of COVID 19 patients that we treat so as to add to the available knowledge in this area. Study of all patients admitted upto 31^st August has already been undertaken by one of the co-investigators. The present study will help us to expand the cohort and give insight into changing clinical pattern of the disease as the epidemic continues to extend. Furthermore, there is also a need to analyze whether the clinical spectrum differs in patients of different age groups. There are limited studies which have compared clinical profile in young, middle aged and the old patients.

1.2  Review of literature: The world is experiencing an unprecedented pandemic caused by novel corona virus (Covid 19). As on 1^st October, there are 6.31 million estimated patients are suffering from COVID 19 in India as per COVID tracker. Understanding about its pathophysiology, clinical features and therapy is gradually increasing. Symptoms of COVID-19 may range from mild to severe, with sizable yet varied fatality rates of 2.3% in China, 7.2% in Italy, and 1.0% in South Korea. ¹ Due to the general susceptibility of new coronaviruses, the clinical characteristics and outcomes of elderly and young patients may be different. The elderly may represent a specific cluster of high-risk patients for developing COVID-19 with rapidly progressive clinical deterioration. Indeed, in older individuals, immunosenescence and comorbid disorders are more likely to promote viral-induced cytokine storm resulting in life-threatening respiratory failure and multi-systemic involvement. ²Kang SJ et al have reported that case fatality rate and susceptibility to symptomatic COVID-19 is higher in the elderly. ³

1.3  Objectives of the present study

To determine and compare clinical, biochemical and radiological profile of young ( 18-35 years), middle aged(36-64 years)and old ( >64 years) admitted patients of COVID 19, their correlation with various comorbidities, and   their outcome.

2. Material and method:

2.1 Source of data: All patients of COVID 19 admitted in COVID isolation wards of Shree Krishna Hospital, Karamsad from 1^st September, 2020 to 31^st December, 2020.

2.2 Methodology [brief description]

- Inclusion: All patients who are COVID-19 positive by RT-PCR/ Rapid Antigen Test and admitted at COVID isolation areas of Shree Krishna Hospital, Karamsad will be included in this study.

- Exclusion criteria: All patients admitted as suspect-Covid in isolation area, but found to be RT-PCR negative.

- Data of all patients will admitted during the period of 1^st September, 2020 to 31^st December 2020 be retrieved from electronic records and its retrospective and prospective analysis will be carried out as regards various clinical, biochemical and radiological parameters  to derive inference about spectrum of disease

Requirement of any investigations or interventions to be conducted on participants - No

2.3 Plan of statistical analysis: Retrospective collection of data.

Descriptive analysis (frequency,%).

Categorical variables will be expressed as numbers and percentages.

Continuous variables will be expressed as mean or median. For the parameters which will be measured multiple times we will estimate the trends.

Association between age, gender, disease severity, complications, co-morbidities, and outcome will be assessed using suitable statistical tests. (Categorical variables – Chi Square test, Continuous Variables – T Test).