A questionnaire codebook defines each variable's name, label, source item, response type, codes, missing-value rules, units, allowed range, and derived logic. It links data collection to analysis and helps prevent ambiguous recoding, especially for skip patterns and reverse-scored items.
Questionnaire Codebook Builder applies this concept to its defined inputs and workflow. It helps make survey data auditable before cleaning, reliability analysis, and statistical reporting.
The helper structures variable lines and returns codebook table, coding summary, and missing-value plan so decisions and omissions can be reviewed explicitly. Input structure, labels, missing values, and selected options must match the intended workflow. It supports preparation and independent checking rather than replacing the governing software, standard, evidence, or professional review. It documents coding but does not validate questionnaire psychometrics.