A study was undeaken to find the relation between COPD and smoking. Patient’s data was collected through records from government hospital and record of cigarettes sale from finance and taxation depaments. Study design?

Social & Preventive Medicine

A study was undeaken to find the relation between COPD and smoking. Patient’s data was collected through records from government hospital and record of cigarettes sale from finance and taxation depaments. Study design?

A study is to be conducted with regards to the fat content…

'There has been a gradual increase in number of non-communicable disease cases…

All of the following are done to remove Confounding except