Oral examination was done by a doctor of dental medicine for dental caries. Hygienic statuses of the respondents were watched attentively during an oral examination. Behavioral data from respondents were collected using questionnaire which is developed in English language and then translated to local language Amharic. The whole data collection process was strictly supervised by the investigators and one dentist professional. The data collectors were recruited based on previous experience and fluency in the local language. In addition, training was given for two consecutive days on how to interview, handling ethical issues and maintaining confidentiality and privacy and how to perform an oral examination.
In order to evaluate the clarity of the data collection instrument, a questionnaire was pre-tested in the nearby health facility other than the study area. Debriefing sessions were held with the pre-test field staff.
Data were checked and entered using EPI-Info version 3.5.3 statistical software. It was cleaned and edited accordingly and exported to SPSS version 20 for analysis. Numerical summary measures, frequencies, proportions were used for describing the study population in relation to relevant variables. Bivariate analysis was done using binary logistic regression. P < 0.25 was used as criteria to select variables for multivariable analysis. Multivariable logistic regression analysis was done to identify important determinants by controlling possible confounding effect. P-value