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A question item is a composite (made up of an question literal, label, response domain) respresentation representation of a single question in a questionnaire.
A question grid is a matrix of questions that all share the same possible answers. It also has an question literal.
Choosing when to use a Question Item
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Question Items are the default choice when entering a question most of the time. They must always include at least one Response Domain and and an question text (literal) that should be able to stand alone contexuallycontextually. Sometimes nearby text has to be concatentated on to inadequate question literals, to display complete context. For example, the sentence 'Smoking:' on it's its own would not be enough for a complete question text, but 'Tell us about your habits: Smoking:' would be. Example 1 below shows a clear example of this, with 'how often did you see him in hospital' being concatenated on to '1st admission' to form a complete question text.
However, if text that would provide clarity/context to a question item is contained entirely within a previous question, such as '1. Do you smoke? 2. How many a day?' these have to be documented as two separate question items, to maintain faithfulness to the original questionnaire (Principle 1).
Choosing when to use a Question Grid
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In general, individual questions are preferable to grids when documenting metadata, due to the simplicity of the former. Question grids become the tool of choice when we are faced with a series of repeating questions such as a food list. A question grid is advantageous to use when:
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