Structured interviews include questions, which are based on systematic analysis and adherence to certain set of rules. Questions in a structured interview are read to the respondent without any deviation from the set protocol. On the other hand, in an unstructured interview, the researcher only follows the topics related to the study. Unstructured interviews do not require the researcher to stick to any script or order, and the interaction with the respondent is more of a conversation as opposed to an interview. While many studies have used unstructured interviews, it is believed that structured interviews are the most effective in terms of validity and reliability.
Structured interviews are good in eliminating bias in data collection. This makes them superior to unstructured interview, which is characterized by informal exchange of non-verbal and verbal information. A structured interview restrains these exchanges by requiring that the same questions should be asked in the same order. By doing so, the researcher/interviewer is restrained in terms of influencing the respondent; thus, a genuine reflection is obtained. On the other hand, using unstructured questions, an interviewer may end up getting results which have been influenced by the manner in which they have conducted the interview as opposed to the real experience of the respondent (Bryman, 2006).
As mentioned above, questions in a structured interview are constructed based on skills, knowledge, and abilities obtained from the past research studies. Further, the questions are structured in a manner that covers all the aspects of the research topic allowing the interviewer to collect only the relevant information. Still, such questions are asked in the same manner and order to all respondents (DiCicco?Bloom & Crabtree, 2006). This allows for consistency and reliability of the data collected. As opposed to the case of unstructured interviews where questions are informal, structured interviews allow the interviewer to rate the data collected on the scale that anchors the good and useful data from the one that may not be good or relevant to the study.
Another attribute of a structured interview that makes it better than unstructured interview is its ability to measure consistency of the data collected. Several safeguards are often used in structured interviews with the aim of measuring consistency. First, interviewers are trained prior to conducting the interview (Bryman, 2006). This equips them with the necessary skills needed to avoid bias. Further, information related to the respondent is withheld prior to the interview, and data analysis begins only after all respondents have been interviewed. On the other hand, using unstructured interview, an interviewer may be prompted to change the questions asked to a respondent based on the answers given by the previous one (DiCicco?Bloom & Crabtree, 2006). In a way, data analysis in unstructured interview is an ongoing process that takes place beginning with the first respondent to the last one.
In conclusion, structured interviews have a better chance of providing the interviewer with reliable, valid, and consistent data as compared with unstructured interview. Structured interviews are based on the analysis of the research topic. The analysis of the research topic allows better sampling as well as increased consistency of the data collected. Further, structured interviews have fewer chances of producing biased data as the questions are asked in the same order and manner. The answers given are not based on how an interview session was conducted but rather are strictly guided by the research topic. The interview process is standardized to ensure increased validity and reliability.