Nigeria - Integrated Biological and Behavioural Surveillance Survey 2007, Second round

After data entry, the data was cleaned using STATA 10. Frequency counts were carried out to check consistency and assess cleanness of the database. The data cleaning also included the following:

Searching for ages outside the age range criteria;
Cross-checking all corresponding skips to the questionnaire;
Reviewing the cluster allocations;
Cross-checking the questionnaire completion responses from the interviewers in the database with the records in the supervisors log to ensure they matched;
Tallying the supervisors log of blood samples collected to ensure that recorded numbers of samples collected matched the results recorded in the database; and
Consistency checks involving cross-checking answers to related questions.

Data was entered using CS Pro version 3.2. A template for the questionnaire was designed with pre-programmed consistency checks for cross-checking answers, including skips and eligibility criteria. Laboratory data forms were collected on a periodic basis from the central laboratories and brought to the same centralized location for data entry.
At least 25% of the questionnaires entered daily by each data entry clerk had the behaviour and other non-biological data entered, while 100% double-data entry was achieved for the biological data for quality control purposes. The data entry clerks were supervised by three supervisors who reviewed and validated all questionnaires entered.