Socio-demographic and clinical characteristics of the study participants.

aP is the Probability of t-test or Chi-square (χ 2) tests. Fisher's exact Chi-square (χ 2) test was used for history of health care work, kidney disease, other disease, smoking status and hospitalization history.b‘Others’ subgroup under ‘Occupation’ includes housewife and self-employed small works.cBDT: Bangladeshi currency.dCavitation related information was not available in 51% of the participants.eOther disease included hypertension, heart diseases, asthma, chronic obstructive pulmonary diseases and chronic dysentery.fHospitalization history had one missing value.