Assess the strengths and weaknesses of using questionnaires to collect data. (20 marks, AS Level)

Questionnaires are commonly used by positivist researchers hoping to gain quantitative data. This can include the government or academic researchers who want to find clear trends about a certain population. As a result, two key strengths of questionnaires are that they are relatively quick, easy and cheap to administer to large numbers of people, and that they can be repeated at different times to spot changing trends. For example, the Welsh Health Survey in 2014 was able to collect data on 14,000 adults and 3,000 children in Wales. By using previous Welsh Health Surveys, it was discovered that 20% of adults smoked in 2014, compared to 26% in 2003-2004. Giving out the questionnaires to 14,000 adults and comparing the results to previous questionnaires provided the evidence of this reduction in smoking, thus showing that two strengths of questionnaires are the ease in administering to large numbers of people, and the ability to compare to previous data and spot trends.However, questionnaires are rarely favoured by interpretivists who prefer qualitative data. This is because it can be hard to use questionnaires to fully gain people's opinions and motivations. For example, the Welsh Health Survey was carried out by the NHS, who most likely want to know why people smoke in order to help them quit. Although researchers can ask in a questionnaire for people's opinions and motivations, it may be hard to gain truly valid data without the face-to-face interaction provided by interviews, for example. Therefore, the Welsh Health Survey may not have enough data of a high quality on why people smoke and how the NHS can help them quit. Another weakness of a questionnaire is that respondents could lie in their responses. Again, this could be less likely with interviews as the face-to-face interaction with the interviewer may put the respondent at ease and encourage them to be honest. This potential lack of trust in a questionnaire can skew the validity of the data. Overall, the lack of qualitative data on respondents' motivations and reasons, and the increased possibility of respondents lying, are key weaknesses of using questionnaires to collect data.