Other resources ebooksclub.org Building Blocks for Tobacco Control A Handbook
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Datacollectionandprocessing
Data collection
Before initiating the collection of data, countries must participate in a workshop to train their research coordinators RCs in the GYTS standard methodology and
procedures. his assures continuity across the regions, consistency in sample design and selection procedures, and questionnaire development ensuring the core remains
intact, and uniformity in field procedures for data collection. Once the training workshop is over, RCs return to their respective countries and
conduct the survey among students in selected schools. Each student completes a questionnaire with responses coded as filled in bubbles on answer sheets. After com-
pleting the data collection of GYTS, the RCs send the survey forms answer and header sheets and school and classroom level forms to CDC for data processing.
Data processing
Answer sheets received by CDC are scanned using optical scanning hardware. Scanned data files proceed through a data cleaning process that includes matching
record length to scanned format, reviewing non-responses out of range and missing and logic editing. Each data record is weight-adjusted for school, class and student
non-participation. Finally, all records are adjusted for grade and gender stratification. here is continuing interaction between CDC staff and the RC and regional office
while cleaning and editing the data file.
Data analysis
Once the data has been collected and processed, WHO and CDC, in collaboration with associate partners, conduct data analysis workshops to provide hands-on train-
ing to the country RCs for an in-depth analysis of their data sets. Analysis workshops include training in the use of EpiInfo free software that encompasses procedures for
analysing complex survey data and country report writing.
Data reporting
Once the data file is finalized, CDC produces 100+ Weighted Frequency Tables and 100+ Preferred Tables. CDC prepares a draft one-page fact sheet highlighting the
main GYTS findings. he final data file, tables and the fact sheet are sent to the cor- responding regional office via e-mail and hard copy.
1. Tabulated data: he raw data are used in calculations for tabulated data. As part of the data processing for GYTS, CDC prepares two types of tables, Weighted Fre-
quency and Preferred Tables: • he Weighted Frequency Tables are produced as separate tables for each question
in the country questionnaires. Tabulations are given for total, by gender and by grade.
• A set of Preferred Tables is produced by CDC, which translates each core question, based on historical classification and including cross comparisons, into variables
that are utilized as indicators to monitor tobacco activity within the country.