Final answer:
The disadvantage that does not apply to self-completion questionnaires is that the respondent can read the entire questionnaire before responding, as this is a feature, not a disadvantage. Questionnaires can contain many closed-ended questions, and may lead to missing data if respondents don't answer all questions.
Step-by-step explanation:
The question you've asked concerns the comparison between self-completion questionnaires and structured interviews in research methodologies. Among the options provided, the one that does not represent a disadvantage of self-completion questionnaires is 'The respondent can read the whole questionnaire before answering the first question.' Self-completion questionnaires can indeed have many closed-ended questions, allowing for quantitative data collection. However, they lack the interactive element of interviews, where a researcher can probe or prompt respondents for more detail. Additionally, there is a risk of missing data as respondents may skip questions.
Qualitative data are results that are subjective and based on what is seen in a natural setting, often requiring deeper responses, such as short essay answers to open-ended questions. In structured interviews, the interviewer asks predetermined questions uniformly and records responses using a standardized system, allowing for accurate comparison between candidates' interviews.