[1] Univ Gondar, Coll Med & Hlth Sci, Inst Publ Hlth, Dept Hlth Informat, Gondar, Ethiopia
[2] Univ Gondar, Inst Publ Hlth, Dept Epidemiol & Biostat, Coll Med & Hlth Sci, Gondar, Ethiopia
[3] Univ British Columbia, Res Pavil,Rm 566,828 W 10th, Vancouver, BC V5Z 1M9, Canada